A cable laying method based on high-drop working well

Abstract

The present application relates to cable laying technical field, provide based on high fall work well cable laying method, including: according to the cable self weight, work well depth and steel wire rope bearing capacity determine the bearing steel wire rope and sectional fixed interval, according to the cable allowable lateral pressure and well mouth traction stress determine the target bending radius of well mouth turning; When laying, the well mouth guiding protection component composed of fixed angle steel support and guiding contact structure is set on the well mouth edge, so that the cable is gently turned from the horizontal section into the vertical section, the sectional fixed interval is used to fix the cable on the bearing steel wire rope by cable clamp, so that the vertical section cable self weight is dispersed and transferred to the steel wire rope; After the cable is in place, the steel wire rope and the cable are fixed and limited, forming the cable laying scheme of well mouth guiding protection, vertical section sectional bearing and stable support cooperation, solving the technical problem that in the existing high fall vertical laying process, the cable self weight and the well mouth turning stress jointly act, which easily leads to the stress concentration of cable and damage.

Description

Technical Field

[0001] This invention relates to the field of cable laying technology, and in particular to a cable laying method based on a high-drop working well. Background Technology

[0002] In construction scenarios such as deep-buried working shafts, pump station shafts, vertical shafts, caissons, and tunnel utility tunnels, cables typically need to first pass through a horizontal laying section near the ground or shaft opening, then transition to a vertical laying section at the shaft opening, and continue downwards along the working shaft to the underground equipment layer or target installation location. Compared to ordinary horizontal laying, vertical cable laying in high-drop working shafts is characterized by a large drop, heavy cable weight, obvious shaft opening bends, and limited working space. When the cable transitions from the horizontal laying section to the vertical laying section, it is subjected to both the tension generated by traction equipment or manual pulling, and the additional load formed by the cable's own weight being transmitted downwards in the vertical laying section. The shaft opening bend area easily becomes a location where the cable's stress is concentrated.

[0003] Existing technologies include construction schemes for vertical cable laying in ultra-high-rise vertical shafts. For example, CN112072560A discloses a method for aerial relay hoisting and vertical laying of cables in ultra-high-rise vertical shafts. This method utilizes a winch, fixed pulley, guide pulley, cable hoisting tool, auxiliary steel wire rope, and cable clamps to achieve segmented relay hoisting of cables within the ultra-high-rise vertical shaft. In this scheme, the cable is assisted in laying horizontally using cable rollers. At bends, the maximum allowable bending radius of the cable cross-section is used. During cable lifting, the cable body is bound to the auxiliary steel wire rope using cable clamps at regular intervals. This type of scheme can improve the construction feasibility of cable traction and hoisting in ultra-high-rise vertical shafts to a certain extent and can provide some support for the cable with the help of auxiliary steel wire ropes. Another method for constructing high-voltage cables over long distances in terrain with significant elevation differences has been proposed. Cable construction in such terrain is challenging due to the large topographical undulations, requiring support and fixation during installation. Additional tension is generated when the cable is suspended or fixed, posing a risk of cable breakage or damage. The method also proposes using construction tools such as combined supports, bearing pulleys, and cable-supporting pulleys suitable for caissons to reduce friction between the cable and the ground or other objects, and to prevent damage to the cable due to excessive bending. The above construction method illustrates that during the laying of high-drop cables, the cable's own weight, support and fixation, friction, and bending control all affect the quality of cable laying and construction safety.

[0004] However, existing construction methods primarily improve the cable laying process by addressing aspects such as traction path layout, pulley guidance, construction tool support, and auxiliary wire rope binding. They do not adequately consider the complex stress issues arising when cables transition from horizontal to vertical laying sections in high-drop working shafts. Particularly at the wellhead, the cable is subjected to both horizontal traction or downward traction and the downward transfer of its own weight from the vertical laying section. This combined effect easily leads to localized stress concentrations along the wellhead edge, near guardrail pre-drilled holes, at the contact points of ordinary guide components, or at the upper fixed positions. If turning is controlled solely based on empirical bending radii, or if the cable is bound to auxiliary wire ropes at fixed intervals, it is difficult to coordinate the control of the cable's vertical weight transfer and the stress at the wellhead turning point based on factors such as the cable's unit length weight, the working shaft depth, the wire rope's load-bearing capacity, the clamping capacity, and the traction stress at the wellhead turning point.

[0005] Therefore, in the current process of vertical laying with high drop, the combined effect of the cable's own weight and the force exerted at the wellhead bend can easily lead to stress concentration on the cable in the wellhead bend area or the upper part of the vertical laying section, which can further cause problems such as cable sheath damage, outer sheath wear, excessive axial tension, local bending damage, or instability in the laying process.

[0006] Therefore, this invention application provides a cable laying method based on a high-drop working well, aiming to solve the above-mentioned problems. Summary of the Invention

[0007] In view of this, embodiments of the present invention provide a cable laying method based on a high-drop working well, in order to solve the technical problem that the cable's own weight and the force exerted by the wellhead turning during the existing high-drop vertical laying process can easily lead to the cable's stress concentration and damage.

[0008] This invention provides a cable laying method based on a high-drop working well, the method comprising: Based on the unit length weight of the cable to be laid, the depth of the working well, and the load-bearing parameters of the wire rope, determine the load-bearing wire rope used to support the cable to be laid and the segmented fixed spacing between the cable to be laid and the load-bearing wire rope. Based on the allowable lateral pressure of the cable to be laid and the traction force of the cable to be laid in the wellhead turning area, determine the target bending radius of the cable when it turns from the horizontal laying section to the vertical laying section. A wellhead guide protection component is installed at the cable lowering position along the edge of the working wellhead. The wellhead guide protection component includes a fixed angle steel bracket and a guide contact structure set on the fixed angle steel bracket. The guide contact structure is located in the wellhead turning area and ensures that the bending radius of the cable to be laid in the wellhead turning area meets the target bending radius. The load-bearing steel wire rope is arranged along the vertical laying section, and the upper end of the load-bearing steel wire rope is limited to the load-bearing limiting position outside the wellhead of the working well, so that the load-bearing steel wire rope remains under stress and limited during the lowering of the cable to be laid. The cable to be laid is guided from the horizontal laying section to the vertical laying section via the guide contact structure. During the process of lowering the cable to be laid along the vertical laying section, the cable to be laid is fixed to the bearing steel wire rope in sections according to the fixed interval of the sections using cable clamps. This allows the self-weight load of the cable to be laid in the vertical laying section to be transferred to the bearing steel wire rope along multiple fixed positions of the sections. After the cable to be laid is lowered to the target installation position, the carrying steel wire rope and the cable to be laid are fixed and limited, so that the carrying steel wire rope forms a load-bearing support for the cable to be laid through the multiple segmented fixed positions.

[0009] Furthermore, the step of determining the bearing wire rope used to support the cable to be laid and the segmented fixed spacing between the cable to be laid and the bearing wire rope, based on the unit length weight of the cable to be laid, the depth of the working well, and the bearing parameters of the wire rope, includes: Based on the model parameters and vertical laying status of the cable to be laid, determine the effective unit length weight of the cable to be laid within the vertical laying section. Based on the working well depth, the starting position of vertical lowering after the wellhead turning area, the target installation position, and the end reserved state, the effective bearing length of the cable to be laid in the vertical laying section is determined. Based on the effective unit length weight and the effective bearing length, determine the maximum self-weight load state of the cable to be laid in the vertical laying section, and determine the safe bearing load limit of the bearing wire rope based on the maximum self-weight load state and the preset safety conditions. Based on the clamping load limit of the cable clamp on the outer sheath of the cable to be laid, the anti-slip load limit between the cable clamp and the carrying steel wire rope, the allowable single-segment suspension load of the cable to be laid between adjacent fixed positions, and the safe bearing load limit of the carrying steel wire rope, the single-segment control load limit between two adjacent fixed positions is determined. Based on the effective unit length weight and the single-segment control load limit, determine the upper limit of the segment fixed spacing, so that the self-weight of the cable to be laid between two adjacent segment fixed positions does not exceed the single-segment control load limit. Based on the effective bearing length and the upper limit of the segmented fixed spacing, multiple segmented fixed positions are determined, and the first segment fixed position near the wellhead turning area, the last segment fixed position near the target installation position, and the theoretical segmented fixed positions that do not meet the on-site safe operation requirements are corrected to obtain multiple actual segmented fixed positions and the actual segmented fixed spacing between two adjacent actual segmented fixed positions. Wherein, the actual segment fixed distance between any two adjacent actual segment fixed positions is not greater than the upper limit of the segment fixed distance; when the corrected actual segment fixed distance is greater than the upper limit of the segment fixed distance, an additional actual segment fixed position is added in the corresponding segment.

[0010] Furthermore, the actual fixed spacing between segments is not greater than a preset fixed spacing threshold, so that the cable to be laid forms an independent stress-bearing segment between two adjacent fixed positions, and the self-weight load in the vertical laying segment is distributed and transferred to the bearing steel wire rope through multiple independent stress-bearing segments.

[0011] Furthermore, the step of determining the target bending radius of the cable to be laid when it transitions from a horizontal laying section to a vertical laying section, based on the allowable lateral pressure of the cable to be laid and the traction force of the cable to be laid in the wellhead turning area, includes: Based on the model parameters, outer diameter, outer sheath structure, and laying requirements of the cable to be laid, determine the allowable lateral pressure limit and the minimum bending radius of the cable body. Obtain the geometric constraint parameters of the wellhead turning area. The geometric constraint parameters include the position of the reserved hole for the cable of the working well guardrail, the wellhead lowering position, the height difference and horizontal offset between the reserved hole for the cable and the wellhead lowering position, the turning angle, and the effective contact length of the guide contact area. Based on the geometric constraint parameters, determine the range of bend radii that can be formed in the field in the wellhead turning area; Based on the resistance state of the cable to be laid in the horizontal laying section and the self-weight transmission state of the cable to be laid in the vertical laying section, the control traction force of the cable to be laid in the wellhead turning area is determined. Based on the controlled traction force and the allowable lateral pressure limit, a first control radius that meets the lateral pressure control requirements is determined; based on the minimum bending radius of the cable body, a second control radius that meets the bending requirements of the cable body is determined. The target bending radius is determined based on the first control radius, the second control radius, and the range of bending radii that can be formed on site.

[0012] Furthermore, the guide contact structure includes a stainless steel guide member, which is disposed on the side of the fixed angle steel bracket near the wellhead turning area, and the stainless steel guide member has an arc-shaped contact surface for supporting the cable to be laid; the radius of curvature of the arc-shaped contact surface matches the target bending radius to increase the contact area between the cable to be laid and the wellhead guide protection member, and to disperse the lateral pressure on the cable to be laid to the arc-shaped contact surface.

[0013] Furthermore, when setting the wellhead guide protection component, the fixed angle steel bracket is fixed to the cable lowering position at the edge of the working wellhead, and the guide contact structure is located between the cable reserved hole of the working well guardrail and the vertical laying section, so as to continuously guide the cable to be laid from the horizontal laying direction to the vertical laying direction.

[0014] Further, the step of guiding the cable to be laid from the horizontal laying section to the vertical laying section via the guide contact structure, and during the process of lowering the cable to be laid along the vertical laying section, fixing the cable to be laid in sections to the carrying steel wire rope according to the fixed interval of the sections using cable clamps, so that the self-weight load of the cable to be laid in the vertical laying section is transferred to the carrying steel wire rope along multiple fixed positions of the sections, includes: Based on the multiple segmented fixed positions, a segmented fixed trigger length corresponding one-to-one with the multiple segmented fixed positions is generated; After the cable to be laid enters the vertical laying section through the guide contact structure, the length of the cable to be laid is determined based on the starting position of the vertical lowering after the wellhead turning area. Based on the length already laid, the previous segment's fixed position, and the effective unit length weight of the cable to be laid, determine the single segment self-weight load corresponding to the current unfixed cable segment. Based on the segmented fixed trigger length, the single-segment self-weight load, and the bending risk status of the wellhead turning area, it is determined whether the segmented fixed trigger conditions are met; wherein, the segmented fixed trigger conditions include conventional trigger conditions and abnormal trigger conditions; The conventional triggering conditions include the lowered length reaching the corresponding segmented fixed triggering length; the abnormal triggering conditions include at least one of the following: the single-segment self-weight load reaches the single-segment control load limit before reaching the corresponding segmented fixed triggering length; the cable to be laid deviates in the wellhead turning area; the contact state of the cable to be laid is abnormal at the guide contact structure; the bearing wire rope slips; and the cable clamp installation position deviates. When the segmented fixing trigger condition is met, reduce the lowering speed or pause the lowering, and install cable clamps at the corresponding segment fixing positions; The cable to be laid is connected to the load-bearing steel wire rope by the cable clamp, so that the cable to be laid and the load-bearing steel wire rope form a load transfer node at the corresponding fixed position of the segment; After the cable clamps are installed, confirm the status of the segment fixing nodes at the current segment fixing position; When the state of the segmented fixed node meets the conditions for continuing to drop down, the current segmented fixed position is taken as the new previous segmented fixed position, and the dropping continues to the next segmented fixed trigger length; When the abnormal triggering conditions are met, the current segment fixed position or the subsequent segment fixed position is corrected according to the position corresponding to the abnormal state, so that the actual segment fixed distance between the corrected adjacent segment fixed positions is not greater than the upper limit of the segment fixed distance.

[0015] Furthermore, the step of fixing and limiting the load-bearing steel wire rope and the cable to be laid after the cable to be laid is lowered to the target installation position, so that the load-bearing steel wire rope forms a load-bearing support for the cable to be laid through the multiple segmented fixed positions, includes: Ground-fixing components are installed around the wellhead of the working well. After the cable to be laid is lowered to the target installation position, the load-bearing steel wire rope is adjusted from the stress-limited state during the lowering process to the fixed load-bearing state, and the load-bearing steel wire rope is fixed to the ground fixing component. The portion of the cable to be laid located at the target installation position is fixed so that the bearing steel wire rope bears at least part of the self-weight load of the cable to be laid in the vertical laying section.

[0016] Furthermore, the ground fixing component includes at least two angle steel members connected back to back, the angle steel members are provided with mounting holes for connecting the load-bearing steel wire rope, and the angle steel members are fixed to the ground foundation around the wellhead of the working well by expansion fasteners; The load-bearing steel wire rope is fixed to the mounting hole by a lifting device, bolts or locking devices.

[0017] Furthermore, when there are multiple cables to be laid, the multiple cables to be laid are laid one by one; After one of the cables to be laid is lowered to the target installation position and fixed and limited, the cable to be laid is limited to the preset cable arrangement position, and then the next cable to be laid is laid, so that the next cable to be laid enters the vertical laying section along a lowering path that is staggered from the fixed cable, so as to avoid multiple cables to be laid from crossing and tangling in the wellhead turning area or the vertical laying section.

[0018] Beneficial effects: Compared with existing technologies, the cable laying method based on a high-drop working well provided in this invention first determines the load-bearing wire rope and segmented fixed spacing based on the cable's unit length weight, the working well depth, and the wire rope's load-bearing parameters. This allows the cable's self-weight in the vertical laying section to be pre-distributed to the wire rope load-bearing system. Then, based on the allowable lateral pressure and the traction force in the wellhead turning area, the target bending radius is determined. Fixed angle steel brackets and guide contact structures guide the cable in the wellhead turning area according to this target bending radius, reducing local compression at the wellhead. Subsequently, during cable lowering, cable clamps are used to fix the cable segments to the load-bearing wire rope at the segmented fixed spacing, transferring the cable's self-weight to the load-bearing wire rope along multiple segmented fixed positions. Finally, fixed limiting treatment maintains the load-bearing support state after laying. Therefore, the main stress points of the cable in the wellhead turning area and the vertical laying section are dispersed and controlled, thereby reducing local stress concentration and avoiding crushing, tensile deformation, or unstable support. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, and these are all within the protection scope of the present invention.

[0020] Figure 1 This is a schematic diagram of the overall process of a cable laying method based on a high-drop working well according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a cable laying structure provided in an embodiment of the present invention; Figure 3 This is a cross-sectional schematic diagram of a working well provided in an embodiment of the present invention.

[0021] in, 1. Working well; 2. Steel wire rope; 3. Wellhead guide and protection components; 4. Horizontal laying section; 5. Fixed angle steel bracket; 6. Cable reserved hole; 8. Cable clamp; 9. Vertical laying section; 10. Stainless steel guide; 11. Cable to be laid. Detailed Implementation

[0022] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the invention.

[0023] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0024] Please see Figures 1 to 3 This invention provides a cable laying method based on a high-drop working well 1, the method comprising: Based on the unit length weight of the cable 11 to be laid, the depth of the working well 1, and the bearing parameters of the wire rope 2, determine the bearing wire rope 2 used to support the cable 11 to be laid and the segmented fixed spacing between the cable 11 to be laid and the bearing wire rope 2. In this embodiment, the cable to be laid 11 refers to the cable that is prepared to be introduced into the working well 1 from the ground or near the wellhead and finally laid to the target position in the well. The weight per unit length reflects the self-weight of the cable per meter. The depth of the working well 1 corresponds to the height that the cable needs to be lowered vertically in the well. The load-bearing parameters of the wire rope 2 include the breaking tensile force, allowable load-bearing capacity and safety factor of the wire rope 2.

[0025] Specifically, based on the depth of the working well 1 measured on-site and the weight per unit length corresponding to the cable type, the total self-weight of the cable within the vertical laying section 9 can be estimated. Then, combined with the load-bearing capacity of the steel wire rope 2, the selected load-bearing steel wire rope 2 can be determined, and the segmented fixing spacing between the cable and the load-bearing steel wire rope 2 can be further determined. This is not simply about arbitrarily binding the cable with the steel wire rope 2, but rather ensuring that the load-bearing steel wire rope 2 and the fixing spacing match the cable's self-weight. This provides a foundation for subsequently distributing and transferring the cable's weight to the steel wire rope 2, reducing the risk of concentrated tension at the upper end of the cable or the wellhead under high drops.

[0026] Based on the allowable lateral pressure of the cable to be laid 11 and the traction force of the cable to be laid 11 in the wellhead turning area, determine the target bending radius corresponding to the cable to be laid 11 when it turns from the horizontal laying section 4 to the vertical laying section 9. In this embodiment, the allowable lateral pressure is the upper limit of pressure that the outer sheath can withstand when the cable is bent, pulled or guided into contact. The wellhead turning area is the position where the direction of the cable changes when it turns from the horizontal laying section 4 into the vertical laying section 9 of the working well 1. The traction force usually comes from the combined action of the winch, manual traction and the cable's own weight.

[0027] Specifically, the allowable lateral pressure can be determined based on the cable specifications. Then, considering the traction resistance of the horizontal laying section 4, the force at the wellhead bend, and the traction force during lowering, the required bending radius of the cable at the wellhead bend can be calculated. This ensures that the cable is not subjected to excessive local compression due to sharp bends during turns. Through this step, the wellhead protection structure has a clear stress basis, allowing control standards to be determined in advance for the bends where the cable is most vulnerable to damage.

[0028] A wellhead guide protection component 3 is installed at the cable lowering position along the edge of the wellhead of the working well 1. The wellhead guide protection component 3 includes a fixed angle steel bracket 5 and a guide contact structure set on the fixed angle steel bracket 5. The guide contact structure is located in the wellhead turning area and makes the bending radius of the cable 11 to be laid in the wellhead turning area meet the target bending radius. In this embodiment, the wellhead guide protection component 3 is a support and protection structure set at the edge of the wellhead of the working well 1, where the cable turns from horizontal to vertical. The fixed angle steel bracket 5 is used to provide a stable installation foundation, and the guide contact structure is used to support the cable and guide the cable to turn smoothly.

[0029] Specifically, the cable lowering position can be determined first at the edge of the wellhead, and the fixed angle steel bracket 5 can be fixed at this position. Then, a guide contact structure with a certain curvature or continuous contact surface can be set on the side of the bracket near the cable contact, so that when the cable enters the wellhead from the guardrail reserved hole or horizontal channel, it can slide or conform to the guide contact structure for turning. Since the guide contact structure is located in the turning area of ​​the wellhead and makes the cable bending radius meet the aforementioned target bending radius, the cable no longer directly presses against the edge of the wellhead or temporary support point, but completes the turning within a continuous and controlled contact area, which helps to reduce damage to the protective layer.

[0030] The load-bearing steel wire rope 2 is arranged along the vertical laying section 9, and the upper end of the load-bearing steel wire rope 2 is limited to the load-bearing limiting position outside the wellhead of the working well 1, so that the load-bearing steel wire rope 2 remains under stress and limited during the lowering of the cable 11 to be laid. In this embodiment, the carrying steel wire rope 2 is not simply suspended in the well along with the cable, but is pre-arranged along the vertical laying section 9 so that it roughly corresponds to the lowering path of the cable 11 to be laid, covering multiple subsequent segmented fixing positions. Its upper end needs to be limited at a stable position outside the wellhead of the working well 1, for example, by ground fixing components, temporary anchors, lifting tools, or locking devices around the wellhead, preventing the carrying steel wire rope 2 from sliding, swinging, or detaching from the predetermined position during cable lowering. The segmented fixing positions are fixed positions determined along the length of the cable 11 to be laid. The cable clamp 8 can be installed in an operable area near the wellhead of the working well 1 between the cable 11 to be laid and the carrying steel wire rope 2, and is lowered with the cable 11 to the corresponding height of the vertical laying section 9. The load-bearing limiting position refers to a fixed or temporary fixing position located outside the wellhead and possessing load-bearing capabilities. Its function is to first ensure that the carrying steel wire rope 2 is in a tensile and limitable state during lowering. In the load-bearing limiting state, the upper end of the load-bearing wire rope 2 is reliably constrained, and the lower end extends vertically along the well. After being subjected to force, the wire rope 2 can transfer the load to the bearing position outside the wellhead without shifting downwards due to the increased weight of the cable. When the cable to be laid 11 is fixed to the load-bearing wire rope 2 in sections using the cable clamp 8, each section fixing position can form a load transfer node. Part of the self-weight load generated by the cable below this position or between adjacent nodes can be transferred to the load-bearing wire rope 2 through the clamp, and then transferred by the load-bearing wire rope 2 to the bearing limiting position outside the wellhead.

[0031] In the above embodiments, the above steps enable segmented fixing to be more than just a formal binding, but to form a stable force-bearing system. After the cable enters the vertical laying section 9 from the horizontal laying section 4, the length of the vertical section continuously increases, and its self-weight also increases accordingly. After the load-bearing wire rope 2 is in a stress-limiting state in advance, it can promptly share the increased suspension load each time the cable clamp 8 is installed, avoiding the cable's self-weight from continuously accumulating along the entire cable to the wellhead turning area. This reduces the risk of bending stress at the wellhead, damage to the outer sheath, and excessive axial tension, and also reduces swaying and instability during the lowering process, making the cable lowering process in the high-drop working well 1 more controllable.

[0032] The cable 11 to be laid is guided from the horizontal laying section 4 to the vertical laying section 9 via the guide contact structure. During the process of the cable 11 being laid down along the vertical laying section 9, the cable 11 is fixed to the bearing steel wire rope 2 in sections according to the fixed interval of the sections using the cable clamps 8. This allows the self-weight load of the cable 11 in the vertical laying section 9 to be transferred to the bearing steel wire rope 2 along multiple fixed positions of the sections. In this embodiment, the vertical laying section 9 is the section where the cable is laid downward along the depth of the well after entering the working well 1. The cable clamp 8 is a connector used to clamp and fix the cable and the carrying steel wire rope 2 at corresponding positions. The segmented fixing positions are the carrying connection points arranged sequentially along the length of the cable.

[0033] Specifically, the cable first smoothly transitions from the horizontal section to the vertical section via a guide contact structure. During the gradual lowering of the cable, construction workers install cable clamps 8 between the cable and the load-bearing steel wire rope 2 at corresponding positions according to pre-determined segmented fixed intervals, creating a synchronous force-bearing connection between the cable and the steel wire rope 2 at multiple locations. In this way, the self-weight generated by the vertical section of the cable is no longer concentrated at the wellhead or the upper end of the cable, but is transferred segment by segment to the load-bearing steel wire rope 2 through multiple cable clamps 8. The steel wire rope 2 then bears the main vertical load, thereby reducing the axial tension and localized deformation of the cable itself.

[0034] After the cable 11 to be laid is lowered to the target installation position, the carrying steel wire rope 2 and the cable 11 to be laid are fixed and limited, so that the carrying steel wire rope 2 forms a bearing support for the cable 11 to be laid through the multiple segmented fixed positions.

[0035] In this embodiment, the fixed limiting treatment refers to fixing, locking, or positionally constraining the load-bearing steel wire rope 2 and the cable after the cable reaches the target installation position, preventing displacement due to their own weight, rebound, swaying, or construction disturbances. In practice, after the lower end of the cable or the target installation position is in place, the load-bearing steel wire rope 2 can be anchored, and the corresponding position of the cable can be fixed, allowing the load-bearing steel wire rope 2 to continue bearing the weight of the vertical section of the cable through multiple segmented fixed positions. This step transforms the temporary segmented load-bearing state during the lowering process into a continuous load-bearing state after laying, avoiding instability caused by the steel wire rope 2 loosening, local slippage, or re-concentration of the cable's own weight after the cable is in place.

[0036] Please see Figures 1 to 3 In one embodiment, the step of determining the bearing wire rope 2 used to support the cable 11 to be laid and the segmented fixed spacing between the cable 11 to be laid and the bearing wire rope 2 based on the unit length weight of the cable 11 to be laid, the depth of the working well 1, and the bearing parameters of the wire rope 2 includes: Based on the model parameters and vertical laying status of the cable 11 to be laid, determine the effective unit length weight of the cable 11 to be laid in the vertical laying section 9. In this embodiment, the model parameters of the cable 11 to be laid may include cable specifications, outer diameter, weight per unit length, and outer sheath structure. The vertical laying state refers to the actual stress state of the cable when it is lowered into the working well 1. The effective weight per unit length is not simply equivalent to the weight per unit length specified by the cable manufacturer, but is corrected based on whether temporary binding parts, protective covering parts, or traction aids are subjected to stress along with the cable during the vertical lowering process.

[0037] In actual operation, if cable segments with different weights exist within the same vertical laying section 9, the weight condition that is more unfavorable to the segment fixing spacing will be used as the basis for determination. By determining the effective unit length weight first, the subsequent segment fixing spacing can be consistent with the actual weight laid on site, avoiding underestimation of the self-weight of a single cable segment due to relying solely on theoretical weight.

[0038] Based on the depth of the working well 1, the starting position of vertical lowering after the wellhead turning area, the target installation position, and the end reserved state, the effective bearing length of the cable to be laid 11 in the vertical laying section 9 is determined. In this embodiment, the effective bearing length is used to characterize the length of the cable 11 to be laid that needs to share the vertical weight of the cable 11 during construction, and its determination cannot be simply equated with the total depth of the working well 1. Specifically, it can be determined from the starting position of vertical lowering after the turning area at the wellhead, combined with the target installation position and the reserved state at the end.

[0039] In actual operation, if the reserved cable at the bottom of the well is still in a suspended state during the lowering process, the reserved part should be included in the effective bearing length during the construction stage; if after the cable reaches the target installation position, part of the cable has been borne by the downhole fixed point, support point or coil state and no longer transmits the vertical self-weight to the vertical laying section 9, then this part can not be regarded as the main control object of the segmented fixed spacing in the final fixed state.

[0040] Through the above steps, the number of fixed positions in each segment is matched with the actual weight of the cable that needs to be dispersed and transferred.

[0041] Based on the effective unit length weight and the effective bearing length, determine the maximum self-weight load state of the cable to be laid 11 in the vertical laying section 9, and determine the safe bearing load limit of the bearing steel wire rope 2 based on the maximum self-weight load state and the preset safety conditions. In this embodiment, the maximum self-weight load state is used to determine the overall load that the load-bearing wire rope 2 needs to withstand during the most unfavorable construction stage. This state typically corresponds to the state before and after the cable is lowered to the target installation position, when the suspension length within the vertical laying section 9 is at its maximum and not yet fully borne by the fixed position in the well. Preset safety conditions can be used to consider the effects of lowering impact, traction fluctuations, bending of the wire rope 2, uneven force on the clamps, and deviations in construction operations. This step distinguishes the overall load-bearing capacity verification from the subsequent determination of the single-segment spacing. That is, the maximum self-weight load state is used to determine whether the overall load-bearing wire rope 2 meets the safety load requirements, while the single-segment self-weight load between two adjacent fixed positions is used to determine whether the segment fixing spacing is appropriate, thereby avoiding increasing the segment spacing solely based on the overall safety of the wire rope 2.

[0042] Based on the clamping load limit of the cable clamp 8 on the outer sheath of the cable to be laid 11, the anti-slip load limit between the cable clamp 8 and the carrying steel wire rope 2, the allowable single-segment suspension load of the cable to be laid 11 between adjacent fixed positions, and the safe bearing load limit of the carrying steel wire rope 2, the single-segment control load limit between two adjacent fixed positions is determined. In this embodiment, the single-segment control load limit is the core parameter for determining the segmented fixed spacing. The clamping load limit of the cable clamp 8 on the cable outer sheath is used to limit the degree of action of the clamp on the cable outer sheath, so that the clamp can prevent the cable from slipping relative to the clamp, but also prevent the cable outer sheath from being indented, locally deformed, or damaged due to excessive clamping. The anti-slip load limit between the cable clamp 8 and the carrying steel wire rope 2 is used to limit the clamp from sliding down or loosening along the steel wire rope 2. The single-segment allowable suspension load is used to limit the free suspension length of the cable between two adjacent segmented fixed positions, avoiding excessive axial tension or localized stress concentration of the cable due to its own weight. The safe bearing load limit of the carrying steel wire rope 2 is used to limit the overall stress state of the steel wire rope 2 after multiple segmented fixed nodes jointly transmit force. The single-segment control load limit should be determined by the more stringent condition among the above-mentioned constraints, and cannot be determined based on only one condition.

[0043] Based on the effective unit length weight and the single-segment control load limit, the upper limit of the segment fixed spacing is determined so that the self-weight of the cable 11 to be laid between two adjacent segment fixed positions does not exceed the single-segment control load limit. In this embodiment, the upper limit of the fixed spacing between segments is jointly limited by the effective unit length weight and the single-segment control load limit. The relationship is as follows: the self-weight of the cable between two adjacent fixed segment positions must not exceed the single-segment control load limit. The larger the effective unit length weight, the smaller the upper limit of the fixed spacing between segments when the single-segment control load limit remains unchanged; when the single-segment control load limit decreases, the fixed segment positions need to be correspondingly denser when the effective unit length weight remains unchanged. Through this step, the fixed spacing between segments can be transformed from an empirical spacing into a load-constrained upper limit, ensuring that the self-weight of each cable segment is limited within a controllable range.

[0044] Based on the effective bearing length and the upper limit of the segmented fixed spacing, multiple segmented fixed positions are determined, and the first segment fixed position near the wellhead turning area, the last segment fixed position near the target installation position, and the theoretical segmented fixed positions that do not meet the on-site safe operation requirements are corrected to obtain multiple actual segmented fixed positions and the actual segmented fixed spacing between two adjacent actual segmented fixed positions.

[0045] In this embodiment, multiple segmented fixing positions are sequentially arranged along the vertical laying section 9 from the starting position of vertical descent after the wellhead turning area to the target installation position downhole. The first fixing position near the wellhead turning area should ensure that the cable completes vertical weight transfer promptly after entering the vertical laying section 9, avoiding excessively long unloaded sections after the wellhead turning area. The last fixing position near the target installation position should be determined based on the end allowance length and downhole fixing conditions to avoid excessively long free-hanging sections at the end. If the theoretical segmented fixing position is located at a high-risk edge of the wellhead, an inconvenient operation position, near well wall obstacles, or a position unfavorable for clamp locking, the theoretical segmented fixing position is adjusted to a nearby safe operation position, and the adjusted adjacent segment lengths are rechecked to ensure they still meet the single-segment control load limit requirements. Through this correction, the segmented fixing spacing meets both the force control requirements and the on-site safe construction requirements.

[0046] Wherein, the actual segment fixed distance between any two adjacent actual segment fixed positions is not greater than the upper limit of the segment fixed distance; when the corrected actual segment fixed distance is greater than the upper limit of the segment fixed distance, an additional actual segment fixed position is added in the corresponding segment.

[0047] Please see Figures 1 to 3 In one embodiment, the actual fixed spacing of the segments is not greater than a preset fixed spacing threshold, so that the cable to be laid 11 forms an independent stress-bearing segment between two adjacent fixed positions, and the self-weight load in the vertical laying segment 9 is distributed and transferred to the bearing steel wire rope 2 through multiple independent stress-bearing segments.

[0048] In this embodiment, the preset fixed spacing threshold is the maximum allowable spacing set based on the cable weight, clamp bearing capacity, wire rope 2 bearing capacity, and construction convenience. An independent stress-bearing section is the cable section between two adjacent fixed positions. During implementation, whenever the cable is lowered along the well to a predetermined height range, a cable clamp 8 is installed, ensuring that the distance between adjacent clamps does not exceed the threshold, thereby dividing the entire vertical cable into multiple shorter stress-bearing sections. Through this arrangement, the weight of each stress-bearing section can be transferred to the supporting wire rope 2 nearby, reducing the concentrated upward transmission of the long-distance cable's self-weight, which helps to reduce the peak stress on individual clamps, the cable sheath, and the area above the wellhead.

[0049] Please see Figures 1 to 3 In one embodiment, the step of determining the target bending radius of the cable 11 when it transitions from the horizontal laying section 4 to the vertical laying section 9, based on the allowable lateral pressure of the cable 11 to be laid and the traction force of the cable 11 to be laid in the wellhead turning area, includes: Based on the model parameters, outer diameter, outer sheath structure and laying requirements of the cable 11 to be laid, determine the allowable lateral pressure limit and the minimum bending radius of the cable body. In this embodiment, cable model parameters, outer diameter, outer sheath structure, and laying requirements are used to determine the boundary conditions that the cable can withstand in the wellhead turning area. The permissible lateral pressure limit primarily restricts the localized compression of the cable outer sheath in the guide contact area, preventing excessive contact pressure between the cable and the guide contact structure that could cause sheath indentation, deformation, or a decrease in insulation performance. The minimum bending radius of the cable body is used to limit the overall bending degree of the cable, preventing structural damage to the conductor, insulation layer, armor layer, and outer sheath due to excessive bending. By simultaneously determining these two parameters, the risks of lateral compression and excessive bending can be controlled separately.

[0050] Obtain the geometric constraint parameters of the wellhead turning area. The geometric constraint parameters include the position of the cable pre-reserved hole 6 of the working well 1 guardrail, the wellhead lowering position, the height difference and horizontal offset between the cable pre-reserved hole 6 and the wellhead lowering position, the turning angle, and the effective contact length of the guide contact area. In this embodiment, the geometric constraint parameters of the wellhead turning area are used to reflect whether a sufficiently smooth turning path can be formed on site. The position of the cable pre-reserved hole 6 in the working well 1 guardrail and the wellhead lowering position determine the start and end positions of the cable entering the vertical section from the horizontal section; the height difference and horizontal offset between the two determine the spatial span of the cable turning process; the turning angle reflects the degree of drastic change in cable direction; and the effective contact length of the guide contact area determines how long the cable can complete the stress distribution along the contact path. By obtaining these parameters, it is possible to avoid designing solely based on the theoretical bending radius while ignoring the limitations of the on-site space conditions at the wellhead.

[0051] Based on the geometric constraint parameters, the range of bend radii that can be formed in the field in the wellhead turning area is determined.

[0052] In this embodiment, the on-site bend radius range is the actual construction boundary determined based on the wellhead geometric constraint parameters. During actual operation, if the height difference between the cable pre-drilled hole 6 and the wellhead lowering position is small, the horizontal offset is short, or the effective contact length of the guide contact area is insufficient, the on-site bend radius range will be smaller, and the cable will more easily form a sharp bend at the wellhead. If the height difference and horizontal offset can provide a longer transition path, and the guide contact area can form a continuous contact surface, the on-site bend radius range will be relatively larger, which is more conducive to reducing lateral pressure.

[0053] In the above embodiments, the above steps can incorporate on-site geometric conditions into the target bending radius determination process, making the target bending radius feasible.

[0054] Based on the resistance state of the cable to be laid in the horizontal laying section 4 and the self-weight transmission state of the cable to be laid in the vertical laying section 9, the control traction force of the cable to be laid in the wellhead turning area is determined. In this embodiment, the resistance state of the horizontal laying section 4 is used to characterize the traction resistance that the cable needs to overcome before entering the wellhead turning area. It can be reflected by the path length of the horizontal laying section 4, the passage status of the pipe, the turning situation, and the traction resistance. The self-weight transfer state of the vertical laying section 9 is used to characterize whether the vertical self-weight of the cable is still transferred to the wellhead turning area after entering the vertical laying section 9. It can be reflected by the length already lowered, the fixing status of the first section near the wellhead area, and whether the cable self-weight has been transferred to the bearing steel wire rope 2 through the cable clamp 8.

[0055] Among them, the greater the resistance of the horizontal laying section 4, the more obvious the traction effect that needs to be overcome at the wellhead; when the self-weight of the vertical laying section 9 has not been transferred in time, the combined force on the wellhead turning area is greater, so a larger control traction force should be determined for subsequent determination of a larger side pressure control radius.

[0056] Based on the controlled traction force and the allowable lateral pressure limit, a first control radius that meets the lateral pressure control requirements is determined; based on the minimum bending radius of the cable body, a second control radius that meets the bending requirements of the cable body is determined. In this embodiment, the first control radius is used to meet the lateral pressure control requirements. The greater the traction force, the larger the first control radius is needed to ensure that the lateral pressure of the cable in the guide contact area does not exceed the allowable lateral pressure limit; conversely, the lower the allowable lateral pressure limit, the more sensitive the cable sheath is to localized compression, also requiring a larger first control radius. The second control radius is used to meet the cable body bending requirements, and its size is related to the cable outer diameter, sheath structure, armor type, and laying specifications. The first control radius focuses on contact compression, while the second control radius focuses on cable structural bending; the risks controlled by the two are different and they cannot be substituted for each other.

[0057] The target bending radius is determined based on the first control radius, the second control radius, and the range of bending radii that can be formed in the field. In this embodiment, the target bending radius should simultaneously meet the requirements of lateral pressure control, cable body bending, and on-site feasibility. When the range of bend radii that can be formed on-site covers the larger of the first control radius and the second control radius, the larger one is used as the target bending radius, ensuring that the cable is neither damaged by excessive lateral pressure nor bent and damaged by excessively sharp turns. When the range of bend radii that can be formed on-site does not meet the larger one, it indicates that the current lowering path or guide contact state is insufficient to safely complete the turn. It is necessary to reduce the stress risk in the wellhead turning area by adjusting the lowering path, increasing the contact transition distance, reducing the control traction force, or pre-fixing in segments.

[0058] In one embodiment, before the cable to be laid 11 enters the wellhead turning area, the actual bending radius of the wellhead turning area is checked to see if it meets the target bending radius. If it does not meet the target bending radius, the lowering path can be adjusted, the contact position of the guide contact area can be adjusted, the lowering speed can be reduced, or the segmented fixing near the wellhead area can be triggered in advance until the actual bending radius meets the target bending radius.

[0059] For example, if the actual turning path of the cable between the pre-drilled hole at the wellhead, the guide contact area, and the starting position of vertical descent is smaller than the target bending radius, it indicates that the cable still faces the risk of sharp bends or excessive lateral pressure. In this case, it is not advisable to continue descent directly. By adjusting the descent path, adjusting the contact position of the guide contact area, reducing the descent speed, or completing the segmented fixing near the wellhead area in advance, the traction force and self-weight transmission in the wellhead turning area can be reduced, so that the actual bending state meets the target bending radius requirements.

[0060] Please see Figures 1 to 3 In one embodiment, the guide contact structure includes a stainless steel guide 10, which is disposed on the side of the fixed angle steel bracket 5 near the wellhead turning area, and the stainless steel guide 10 has an arc-shaped contact surface for supporting the cable 11 to be laid; the radius of curvature of the arc-shaped contact surface matches the target bending radius to increase the contact area between the cable 11 to be laid and the wellhead guide protection member 3, and to disperse the lateral pressure on the cable 11 to be laid to the arc-shaped contact surface.

[0061] In this embodiment, the stainless steel guide 10 is a component that contacts the cable and provides smooth guidance. The arc-shaped contact surface allows the cable to turn along a gentler curve, rather than contacting sharp edges or point supports. In implementation, the stainless steel guide 10 can be installed on the side of the fixed angle steel bracket 5 near the cable bend, allowing the cable to slide down close to or against the arc-shaped contact surface after entering the wellhead from the horizontal section. Because the stainless steel surface is relatively smooth and wear-resistant, it reduces scratches between the cable sheath and the guide. By increasing the contact area, the lateral pressure originally concentrated at the wellhead edge is distributed to the arc-shaped contact surface, helping to reduce the risk of sheath indentation, scratches, and localized damage.

[0062] Please see Figures 1 to 3 In one embodiment, when setting the wellhead guide protection component 3, the fixed angle steel bracket 5 is fixed to the cable lowering position at the edge of the wellhead of the working well 1, and the guide contact structure is located between the cable reserved hole 6 of the working well 1 guardrail and the vertical laying section 9, so as to continuously guide the cable 11 to be laid from the horizontal laying direction to the vertical laying direction.

[0063] In this embodiment, the cable pre-drilled hole 6 in the guardrail of the working well 1 serves as the channel for the cable to enter the well area from the outside of the wellhead, and the vertical laying section 9 is the path for the cable to extend downwards after entering the working well 1. The area between these two sections is precisely where the cable direction change is most concentrated. In practice, the fixed angle steel bracket 5 is securely installed at the cable lowering position along the edge of the wellhead, and the guide contact structure is positioned between the pre-drilled hole and the vertical laying section 9. After passing through the pre-drilled hole, the cable is supported by the guide contact structure and gradually turns downwards. This arrangement reduces the cable's suspended bending and disorderly swaying between the pre-drilled hole outlet and the lowering point inside the well, ensuring a continuous and smooth cable turning process, and further reducing the risk of localized scraping and crushing at the wellhead.

[0064] Please see Figures 1 to 3 In one embodiment, the step of guiding the cable 11 to be laid from the horizontal laying section 4 to the vertical laying section 9 via the guide contact structure, and during the process of lowering the cable 11 along the vertical laying section 9, fixing the cable 11 to the bearing steel wire rope 2 in segments according to the segmented fixed intervals using cable clamps 8, so that the self-weight load of the cable 11 to be laid in the vertical laying section 9 is transferred to the bearing steel wire rope 2 along multiple segmented fixed positions, includes: Based on the multiple segmented fixed positions, a segmented fixed trigger length corresponding one-to-one with the multiple segmented fixed positions is generated; In this embodiment, the corresponding segmented fixing positions are determined based on the clamp arrangement positions according to the aforementioned segmented fixing spacing. The cable clamp 8 is installed between the cable and the load-bearing steel wire rope 2 to establish a force connection between them. During implementation, the segmented fixing trigger length transforms the segmented fixing positions determined before construction into execution nodes during the cable lowering process. That is, the segmented fixing trigger length is not an arbitrarily set construction distance, but is jointly determined by the effective unit length weight, the single-segment control load limit, the upper limit of the segmented fixing spacing, and the segmented fixing positions after boundary correction. This step provides clear triggering criteria for the deceleration, pause, and clamp installation actions during cable lowering, avoiding the need for construction personnel to rely solely on experience to determine the fixing timing.

[0065] After the cable 11 to be laid enters the vertical laying section 9 through the guide contact structure, the length of the cable 11 to be laid is determined based on the starting position of vertical lowering after the wellhead turning area.

[0066] In this embodiment, the lowered length reflects the actual suspension length of the cable after it enters the vertical laying section 9. The starting position of the vertical lowering after the wellhead turning area is used as the length reference because the main vertical suspension force only begins to form after the cable transitions from the horizontal laying section 4 to the vertical laying section 9. This length reference avoids conflating the calculation of the length of the horizontal laying section 4, the length of the wellhead guide transition section, and the vertical suspension length, ensuring that subsequent triggering judgments more closely reflect the actual stress state of the vertical laying section 9.

[0067] Based on the length already laid, the previous segment's fixed position, and the effective unit length weight of the cable 11 to be laid, determine the single segment self-weight load corresponding to the current unfixed cable segment. In this embodiment, the currently unfixed cable segment refers to the cable segment that has not yet formed a load transfer connection with the load-bearing steel wire rope 2 after the previous segment has been fixed. As the cable continues to be lowered, the length of this cable segment gradually increases, and the corresponding single-segment self-weight load also gradually increases. By determining the single-segment self-weight load based on the lowered length, the previous segment's fixing position, and the effective unit length weight, it can be determined whether the unfixed segment is close to the determined single-segment control load limit. After the above steps, the segment fixing trigger no longer depends solely on distance, but corresponds to the actual self-weight load of the currently unfixed cable segment, which can reduce the risk of axial tension or localized stress concentration caused by an excessively long single segment.

[0068] Based on the segmented fixed trigger length, the single-segment self-weight load, and the bending risk status of the wellhead turning area, it is determined whether the segmented fixed trigger conditions are met; wherein, the segmented fixed trigger conditions include conventional trigger conditions and abnormal trigger conditions; The conventional triggering conditions include the lowered length reaching the corresponding segmented fixed triggering length; the abnormal triggering conditions include at least one of the following: the single-segment self-weight load reaches the single-segment control load limit before reaching the corresponding segmented fixed triggering length; the cable to be laid 11 deviates in the wellhead turning area; the contact state of the cable to be laid 11 at the guide contact structure is abnormal; the bearing wire rope 2 slips; and the cable clamp 8 deviates from its installation position.

[0069] In this embodiment, the segmented fixing trigger condition is used to determine whether it is necessary to reduce the lowering speed, pause the lowering, or perform segmented fixing. Regular trigger conditions may include the lowered length reaching the current segmented fixing trigger length, or the self-weight load of the single segment corresponding to the currently unfixed cable segment reaching a preset trigger threshold. Abnormal trigger conditions may include, before the regular trigger conditions are met, the bending risk state of the wellhead turning area not meeting the requirements for continued lowering, or abnormal lowering states such as lowering obstruction, sudden force changes, abnormal lowering speed, abnormal outer sheath contact, or abnormal cable posture occurring. The bending risk state of the wellhead turning area can be reflected by the relationship between the actual bending radius and the target bending radius, the contact state of the guide contact area, and the pressure state of the outer sheath; this part can be further elaborated in the embodiments of the specification. By distinguishing between regular and abnormal trigger conditions, the normal segmented fixing process based on length and load can be retained, while allowing for early intervention when abnormal forces or wellhead bending risks occur on-site.

[0070] When the segmented fixing trigger condition is met, reduce the lowering speed or pause the lowering, and install the cable clamp 8 at the corresponding segment fixing position; In this embodiment, after the segmented fixing trigger condition is met, the lowering speed is reduced or the lowering is paused. This reduces the dynamic swaying and descent tendency of the cable during the lowering process, allowing the cable clamp 8 to be installed in a more stable state. The corresponding segmented fixing position can be the originally planned segmented fixing position; when the segmented fixing trigger condition is triggered by an abnormal trigger condition, the corresponding segmented fixing position can also be the safe operating position adjusted according to the abnormal lowering state. Through this step, the installation action of the cable clamp 8 matches the actual stress state of the cable, avoiding clamping and fixing when the cable is still in a rapid lowering or unstable stress state.

[0071] The cable to be laid 11 is connected to the carrying steel wire rope 2 by the cable clamp 8, so that the cable to be laid 11 and the carrying steel wire rope 2 form a load transfer node at the corresponding segment fixing position; after the cable clamp 8 is installed, the segment fixing node status at the current segment fixing position is confirmed. In this embodiment, after the cable clamp 8 is installed, the corresponding segment fixing position is not just a simple binding position, but a load transfer node between the cable and the carrying steel wire rope 2. This node can transfer the vertical self-weight generated by the previous cable segment to the carrying steel wire rope 2, reducing the transfer of this self-weight to the wellhead turning area, the upper cable, or the previous fixing node. By forming multiple load transfer nodes sequentially along the vertical laying section 9, the cable self-weight can be transformed from being concentrated on the whole section to being stressed on multiple single sections, thereby reducing the axial tension and local stress concentration of the cable body during the high-drop descent.

[0072] In the above embodiments, the segmented fixing node status is used to characterize whether a stable load transfer node has been formed at the current segment fixing position. This can include the clamping state between the cable 11 to be laid and the cable clamp 8, the locking state between the cable clamp 8 and the carrying steel wire rope 2, the attitude state of the cable 11 to be laid within the current segment, and the pressure state of the outer sheath of the cable 11 at the clamp position and guide contact position. By uniformly classifying these states into the segmented fixing node status, it is possible to avoid listing too many specific inspection conditions in the main steps of the method, while still reflecting key risks such as whether the clamping is stable, whether the connection of the steel wire rope 2 is reliable, and whether the cable is twisted or locally compressed. Only when the segmented fixing node status meets the requirements for continued lowering is it stated that the current segment fixing position can stably bear the self-weight load of the corresponding cable segment and transfer it to the carrying steel wire rope 2.

[0073] When the state of the segmented fixed node meets the conditions for continuing to drop down, the current segmented fixed position is taken as the new previous segmented fixed position, and the dropping continues to the next segmented fixed trigger length; In this embodiment, the current segment fixing position meets the conditions for continued lowering, indicating that this position has formed an effective load transfer node and can serve as a new starting point for subsequent single-segment self-weight load calculations. As the cable continues to be lowered, the previous segment fixing position of the currently unfixed cable segment is recalculated, ensuring that the self-weight of each cable segment is limited within the corresponding single-segment control load limit. This segment-by-segment resetting method forms a progressively advancing load transfer chain, preventing the continuous concentrated application of the cable's self-weight across the entire vertical laying section 9 to the wellhead turning area or the uppermost fixing position.

[0074] When the abnormal triggering conditions are met, the current segment fixed position or the subsequent segment fixed position is corrected according to the position corresponding to the abnormal state, so that the actual segment fixed distance between the corrected adjacent segment fixed positions is not greater than the upper limit of the segment fixed distance. In this embodiment, this step enables the correction of segment positions after an abnormal trigger. An abnormal lowering state indicates that the cable, before reaching the current segment's fixed trigger length or a preset trigger threshold, has encountered a risky condition unsuitable for continued lowering according to the original trigger length. This can include lowering obstruction, sudden changes in force, abnormal lowering speed, insufficient actual bending radius in the wellhead turning area, abnormal outer sheath contact, or abnormal cable posture. When the aforementioned abnormal state triggers segment fixing, it indicates that the original segment fixing position or original trigger length is no longer fully compatible with the current construction stress state. It is necessary to consider the location of the abnormality, advance or adjust the current segment fixing position to a nearby safe operating position, and compensate for and correct the fixing positions of subsequent segments so that the corrected adjacent segments still meet the single-segment control load limit requirements.

[0075] Please see Figures 1 to 3 In one embodiment, the step of fixing and limiting the load-bearing steel wire rope 2 and the cable 11 to be laid after the cable 11 to be laid is lowered to the target installation position, so that the load-bearing steel wire rope 2 forms a load-bearing support for the cable 11 to be laid through the multiple segmented fixed positions, includes: Ground fixing components are installed around the wellhead of working well 1; In this embodiment, the ground fixing component is a load-bearing structure installed on the ground surrounding the wellhead of the working well 1, which can be used to withstand the vertical or oblique tension transmitted by the wire rope 2. During implementation, the installation position of the ground fixing component can be determined based on the foundation strength of the ground around the wellhead, the position of the guardrail, the direction of the wire rope 2, and the construction space. It is then fixed to the concrete ground or other reliable foundation by welding, bolt anchoring, or expansion fastening. This step provides the load-bearing wire rope 2 with a stable external support point, providing structural conditions for the wire rope 2 to continuously bear the self-weight of the cable.

[0076] After the cable 11 to be laid is lowered to the target installation position, the load-bearing steel wire rope 2 is adjusted from the force-limited state during the lowering process to the fixed load-bearing state, and the load-bearing steel wire rope 2 is fixed to the ground fixing component. In this embodiment, after the cable is lowered to the target installation position, the weight of the cable within the vertical laying section 9 has been connected to the load-bearing steel wire rope 2 through multiple segmented fixed positions. At this point, it is necessary to reliably fix the load-bearing steel wire rope 2 to prevent slippage or loosening. In practice, the load-bearing steel wire rope 2 can be connected to the ground-fixed components and tightened using lifting tools, bolts, locking devices, or rope clamps to maintain a stable load-bearing state. Through this step, the steel wire rope 2 can transfer the cable load from the multiple segmented fixed positions to the ground-fixed components, preventing the cable from sagging or experiencing force reconcentration after it has been positioned due to the support end not being locked.

[0077] The portion of the cable 11 to be laid located at the target installation position is fixed so that the bearing steel wire rope 2 bears at least part of the self-weight load of the cable 11 to be laid within the vertical laying section 9.

[0078] In this embodiment, the cable at the target installation location can be fixed using brackets, binding, clamping, or in conjunction with the downhole equipment installation structure, ensuring that the cable does not shift due to swinging, rebounding, or construction disturbances after lowering. During implementation, after the wire rope 2 is fixed, the cable section is tidied and limited to ensure the cable path meets design requirements, while maintaining the segmented connection between the cable and the load-bearing wire rope 2. By having the wire rope 2 bear at least part of its own weight, and with the additional limiting measures at the target installation location, the overall stability after laying is improved, preventing the cable ends or vertical sections from being under uncontrolled stress for extended periods.

[0079] Please see Figures 1 to 3 In one embodiment, the ground fixing component includes at least two angle steel members connected back to back, the angle steel members are provided with mounting holes for connecting the bearing steel wire rope 2, and the angle steel members are fixed to the ground foundation around the wellhead of the working well 1 by expansion fasteners; In this embodiment, the back-to-back connected angle steel members can form a relatively stable combined load-bearing structure. The mounting holes are used to provide a fixed position for the wire rope 2 connector, and the expansion fasteners are used to anchor the angle steel members to the ground foundation around the wellhead. In implementation, two or more angle steels can be welded or connected back-to-back to form the main body of the fixed component. Then, mounting holes are opened on the angle steel members, and they are fixed to the concrete ground with fasteners such as expansion bolts. This structure is easy to obtain materials for and simple to process, and can quickly form wire rope 2 anchor points with high tensile stability on the construction site.

[0080] The load-bearing steel wire rope 2 is fixed to the mounting hole by a lifting device, bolts or locking devices.

[0081] In this embodiment, the lifting device, bolt, or locking device can all serve as connecting components between the wire rope 2 and the mounting hole, enabling a detachable and reliable load-bearing connection. In practice, the end of the wire rope 2 can be connected to the mounting hole via the lifting device, or a locking structure can be formed using bolts, locking devices, rope clamps, etc., preventing the wire rope 2 from detaching from the mounting hole under load. Through this connection method, the load-bearing capacity of the wire rope 2 can be stably transferred to the ground-fixed components, facilitating post-construction inspection, adjustment, or disassembly, while also enhancing the safety support capacity after vertical laying is completed.

[0082] Please see Figures 1 to 3 In one embodiment, when there are multiple cables 11 to be laid, the multiple cables 11 to be laid are laid one by one; In this embodiment, laying multiple cables 11 one by one means that only one cable is guided, lowered, segmented, fixed, and limited at a time, rather than introducing multiple cables into the wellhead and lowering them at the same time.

[0083] Specifically, construction can be carried out sequentially according to cable number, installation location, or wiring order. First, the wellhead guidance and vertical laying of the first cable are completed, and then the next cable is laid. Due to the limited space at the wellhead of the high-drop working well 1, laying each cable one by one can keep the lowering path and stress path of each cable clear, reducing mutual compression, entanglement, or cross-interference between cables.

[0084] After one of the cables to be laid 11 is lowered to the target installation position and fixed and limited, the cable to be laid 11 is limited to the preset cable arrangement position, and then the next cable to be laid 11 is laid, so that the next cable to be laid 11 enters the vertical laying section 9 along a lowering path that is staggered from the fixed cable, so as to avoid multiple cables to be laid 11 from crossing and tangling in the wellhead turning area or the vertical laying section 9.

[0085] In this embodiment, the laying of the next cable only begins after the current cable has been lowered to the target installation position and both the supporting steel wire rope 2 and the cable have been fixed and limited. This ensures that the previous cable is in a stable state and will not continue to swing or occupy uncertain space during subsequent construction.

[0086] Specifically, after each cable is positioned in the well, the wire rope is anchored, and the cable is limited, an inspection and confirmation can be carried out before the next cable is introduced into the vertical laying section 9 via the wellhead guide and protection component 3. This method can avoid multiple cables overlapping in the wellhead turning area, getting tangled in the vertical well, or causing damage to the protective layer due to mutual friction, thereby improving the construction quality and safety of laying multiple cables.

[0087] It should be clarified that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of the present invention.

[0088] It should also be noted that the exemplary embodiments mentioned in this invention describe methods or systems based on a series of steps or apparatus. However, this invention is not limited to the order of the steps described above; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0089] The above description is merely a specific embodiment of the present invention. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific implementation processes of the above methods and steps can be referred to each other, and will not be repeated here. It should be understood that the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. A cable laying method based on a high-drop working well, characterized in that, The method includes: Based on the unit length weight of the cable to be laid, the depth of the working well, and the load-bearing parameters of the wire rope, determine the load-bearing wire rope used to support the cable to be laid and the segmented fixed spacing between the cable to be laid and the load-bearing wire rope. Based on the allowable lateral pressure of the cable to be laid and the traction force of the cable to be laid in the wellhead turning area, determine the target bending radius of the cable when it turns from the horizontal laying section to the vertical laying section. A wellhead guide protection component is installed at the cable lowering position along the edge of the working wellhead. The wellhead guide protection component includes a fixed angle steel bracket and a guide contact structure set on the fixed angle steel bracket. The guide contact structure is located in the wellhead turning area and ensures that the bending radius of the cable to be laid in the wellhead turning area meets the target bending radius. The load-bearing steel wire rope is arranged along the vertical laying section, and the upper end of the load-bearing steel wire rope is limited to the load-bearing limiting position outside the wellhead of the working well, so that the load-bearing steel wire rope remains under stress and limited during the lowering of the cable to be laid. The cable to be laid is guided from the horizontal laying section to the vertical laying section via the guide contact structure. During the process of lowering the cable to be laid along the vertical laying section, the cable to be laid is fixed to the bearing steel wire rope in sections according to the fixed interval of the sections using cable clamps. This allows the self-weight load of the cable to be laid in the vertical laying section to be transferred to the bearing steel wire rope along multiple fixed positions of the sections. After the cable to be laid is lowered to the target installation position, the carrying steel wire rope and the cable to be laid are fixed and limited, so that the carrying steel wire rope forms a load-bearing support for the cable to be laid through the multiple segmented fixed positions; The step of determining the target bending radius of the cable to be laid when it transitions from a horizontal laying section to a vertical laying section, based on the allowable lateral pressure of the cable to be laid and the traction force of the cable in the wellhead turning area, includes: Based on the model parameters, outer diameter, outer sheath structure, and laying requirements of the cable to be laid, determine the allowable lateral pressure limit and the minimum bending radius of the cable body. Obtain the geometric constraint parameters of the wellhead turning area. The geometric constraint parameters include the position of the reserved hole for the cable of the working well guardrail, the wellhead lowering position, the height difference and horizontal offset between the reserved hole for the cable and the wellhead lowering position, the turning angle, and the effective contact length of the guide contact area. Based on the geometric constraint parameters, determine the range of bend radii that can be formed in the field in the wellhead turning area; Based on the resistance state of the cable to be laid in the horizontal laying section and the self-weight transmission state of the cable to be laid in the vertical laying section, the control traction force of the cable to be laid in the wellhead turning area is determined. Based on the controlled traction force and the allowable lateral pressure limit, a first control radius that meets the lateral pressure control requirements is determined; based on the minimum bending radius of the cable body, a second control radius that meets the bending requirements of the cable body is determined. The target bending radius is determined based on the first control radius, the second control radius, and the range of bending radii that can be formed on site.

2. The cable laying method based on a high-drop working well according to claim 1, characterized in that, The step of determining the load-bearing steel wire rope used to support the cable to be laid and the segmented fixed spacing between the cable to be laid and the load-bearing steel wire rope based on the unit length weight of the cable to be laid, the depth of the working well, and the load-bearing parameters of the steel wire rope includes: Based on the model parameters and vertical laying status of the cable to be laid, determine the effective unit length weight of the cable to be laid within the vertical laying section. Based on the working well depth, the starting position of vertical lowering after the wellhead turning area, the target installation position, and the end reserved state, the effective bearing length of the cable to be laid in the vertical laying section is determined. Based on the effective unit length weight and the effective bearing length, determine the maximum self-weight load state of the cable to be laid in the vertical laying section, and determine the safe bearing load limit of the bearing wire rope based on the maximum self-weight load state and the preset safety conditions. Based on the clamping load limit of the cable clamp on the outer sheath of the cable to be laid, the anti-slip load limit between the cable clamp and the carrying steel wire rope, the allowable single-segment suspension load of the cable to be laid between adjacent fixed positions, and the safe bearing load limit of the carrying steel wire rope, the single-segment control load limit between two adjacent fixed positions is determined. Based on the effective unit length weight and the single-segment control load limit, determine the upper limit of the segment fixed spacing, so that the self-weight of the cable to be laid between two adjacent segment fixed positions does not exceed the single-segment control load limit. Based on the effective bearing length and the upper limit of the segmented fixed spacing, multiple segmented fixed positions are determined, and the first segment fixed position near the wellhead turning area, the last segment fixed position near the target installation position, and the theoretical segmented fixed positions that do not meet the on-site safe operation requirements are corrected to obtain multiple actual segmented fixed positions and the actual segmented fixed spacing between two adjacent actual segmented fixed positions. Wherein, the actual segment fixed distance between any two adjacent actual segment fixed positions is not greater than the upper limit of the segment fixed distance; when the corrected actual segment fixed distance is greater than the upper limit of the segment fixed distance, an additional actual segment fixed position is added in the corresponding segment.

3. The cable laying method based on a high-drop working well according to claim 2, characterized in that, The actual fixed spacing between segments is not greater than the preset fixed spacing threshold, so that the cable to be laid forms an independent stress-bearing segment between two adjacent fixed positions, and the self-weight load in the vertical laying segment is distributed and transferred to the bearing steel wire rope through multiple independent stress-bearing segments.

4. The cable laying method based on a high-drop working well according to claim 1, characterized in that, The guide contact structure includes a stainless steel guide component, which is disposed on the side of the fixed angle steel bracket near the wellhead turning area. The stainless steel guide component has an arc-shaped contact surface for supporting the cable to be laid. The radius of curvature of the arc-shaped contact surface matches the target bending radius to increase the contact area between the cable to be laid and the wellhead guide protection component, and to disperse the lateral pressure on the cable to be laid to the arc-shaped contact surface.

5. The cable laying method based on a high-drop working well according to claim 1, characterized in that, When setting up the wellhead guide protection component, the fixed angle steel bracket is fixed to the cable lowering position at the edge of the working wellhead, and the guide contact structure is located between the cable reserved hole of the working well guardrail and the vertical laying section, so as to continuously guide the cable to be laid from the horizontal laying direction to the vertical laying direction.

6. The cable laying method based on a high-drop working well according to claim 3, characterized in that, The steps of guiding the cable to be laid from the horizontal laying section to the vertical laying section via the guide contact structure, and during the process of lowering the cable to be laid along the vertical laying section, fixing the cable to be laid in sections to the bearing steel wire rope according to the fixed interval of the sections using cable clamps, so that the self-weight load of the cable to be laid in the vertical laying section is transferred to the bearing steel wire rope along multiple fixed positions of the sections, include: Based on the multiple segmented fixed positions, a segmented fixed trigger length corresponding one-to-one with the multiple segmented fixed positions is generated; After the cable to be laid enters the vertical laying section through the guide contact structure, the length of the cable to be laid is determined based on the starting position of the vertical lowering after the wellhead turning area. Based on the length already laid, the previous segment's fixed position, and the effective unit length weight of the cable to be laid, determine the single segment self-weight load corresponding to the current unfixed cable segment. Based on the segmented fixed trigger length, the single-segment self-weight load, and the bending risk status of the wellhead turning area, it is determined whether the segmented fixed trigger conditions are met; wherein, the segmented fixed trigger conditions include conventional trigger conditions and abnormal trigger conditions; The conventional triggering conditions include the lowered length reaching the corresponding segmented fixed triggering length; the abnormal triggering conditions include at least one of the following: the single-segment self-weight load reaches the single-segment control load limit before reaching the corresponding segmented fixed triggering length; the cable to be laid deviates in the wellhead turning area; the contact state of the cable to be laid is abnormal at the guide contact structure; the bearing wire rope slips; and the cable clamp installation position deviates. When the segmented fixing trigger condition is met, reduce the lowering speed or pause the lowering, and install cable clamps at the corresponding segment fixing positions; The cable to be laid is connected to the load-bearing steel wire rope by the cable clamp, so that the cable to be laid and the load-bearing steel wire rope form a load transfer node at the corresponding fixed position of the segment; After the cable clamps are installed, confirm the status of the segment fixing nodes at the current segment fixing position; When the state of the segmented fixed node meets the conditions for continuing to drop down, the current segmented fixed position is taken as the new previous segmented fixed position, and the dropping continues to the next segmented fixed trigger length; When the abnormal triggering conditions are met, the current segment fixed position or the subsequent segment fixed position is corrected according to the position corresponding to the abnormal state, so that the actual segment fixed distance between the corrected adjacent segment fixed positions is not greater than the upper limit of the segment fixed distance.

7. The cable laying method based on a high-drop working well according to claim 1, characterized in that, The step of fixing and limiting the load-bearing steel wire rope and the cable to be laid after the cable to be laid is lowered to the target installation position, so that the load-bearing steel wire rope forms a load-bearing support for the cable to be laid through the multiple segmented fixed positions, includes: Ground-fixing components are installed around the wellhead of the working well. After the cable to be laid is lowered to the target installation position, the load-bearing steel wire rope is adjusted from the stress-limited state during the lowering process to the fixed load-bearing state, and the load-bearing steel wire rope is fixed to the ground fixing component. The portion of the cable to be laid located at the target installation position is fixed so that the bearing steel wire rope bears at least part of the self-weight load of the cable to be laid in the vertical laying section.

8. The cable laying method based on a high-drop working well according to claim 7, characterized in that, The ground fixing component includes at least two angle steel members connected back to back. The angle steel members are provided with mounting holes for connecting the load-bearing steel wire rope. The angle steel members are fixed to the ground foundation around the wellhead of the working well by expansion fasteners. The load-bearing steel wire rope is fixed to the mounting hole by a lifting device, bolts or locking devices.

9. The cable laying method based on a high-drop working well according to any one of claims 1 to 8, characterized in that, When there are multiple cables to be laid, the cables shall be laid one by one. After one of the cables to be laid is lowered to the target installation position and fixed and limited, the cable to be laid is limited to the preset cable arrangement position, and then the next cable to be laid is laid, so that the next cable to be laid enters the vertical laying section along a lowering path that is staggered from the fixed cable, so as to avoid multiple cables to be laid from crossing and tangling in the wellhead turning area or the vertical laying section.

Images