A joint structure for preventing falling off during directional drilling construction of finished hot water pipeline

Abstract

The present invention discloses a joint structure for preventing a finished hot water pipe from falling off during directional drilling construction, comprising a working pipe, including an inner core pipe and an outer insulation pipe; a connecting pipe, which has the same diameter as the inner core pipe and is welded and fixedly connected to the inner core pipe; a plurality of protective steel plates are evenly distributed on the outer wall of the connecting pipe along its circumferential direction, one end of the protective steel plate is welded and fixedly connected to the connecting pipe, the other end of the protective steel plate extends to the outer wall of the outer insulation pipe and abuts against the outer wall of the outer insulation pipe, and one end of the connecting pipe away from the working pipe is closed and provided with a drag connector. In view of the technical problem that the insulation layer of the existing finished hot water pipe is easy to fall off during the directional back-dragging process, the present invention provides a joint structure for preventing a finished hot water pipe from falling off during directional drilling construction, which can reduce the resistance of the soil during the back-dragging process of directional drilling, protect the insulation layer of the finished hot water pipe, and prevent the insulation joint from falling off during the back-dragging process.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline construction, and in particular to a joint structure for preventing falling off during directional drilling construction of a finished hot water pipeline. Background Art

[0002] According to the 4.5.2 of the "Code for Construction and Acceptance of Urban Heating Pipe Network Projects" CJJ28, directional drilling construction should not be used for direct pulling of buried pipes. However, with the improvement of urban road network systems and the improvement of urban landscape requirements, it is not allowed to use trenchless technology for partial laying when overhead and direct burial construction is not allowed.

[0003] During the directional pullback process of the finished hot water pipe, the most concentrated force is at the connection between the pulling head and the pipe end. The insulation layer of the finished hot water pipe is made of high-density polyethylene and cannot be directly welded to the pulling head. If the insulation layer is not protected during the pullback process, it may be separated from the core pipe, resulting in insulation failure and pipeline corrosion damage. Summary of the invention

[0004] 1. Technical problem to be solved by the invention

[0005] In view of the technical problem that the insulation layer of the existing finished hot water pipe is easy to fall off during the directional backhauling process, the present invention provides a joint structure for preventing the finished hot water pipe from falling off during directional drilling construction, which can reduce the resistance of the soil during the directional drilling backhauling process, protect the insulation layer of the finished hot water pipe, and prevent the insulation joint from falling off during the backhauling process.

[0006] 2. Technical solution

[0007] To solve the above problems, the technical solution provided by the present invention is:

[0008] A joint structure for preventing a finished hot water pipe from falling off during directional drilling construction, comprising a working pipe, including an inner core pipe and an outer insulation pipe; a connecting pipe, which has the same diameter as the inner core pipe and is welded and fixedly connected to the inner core pipe; a plurality of protective steel plates are evenly distributed on the outer wall of the connecting pipe along its circumferential direction, one end of the protective steel plate is welded and fixedly connected to the connecting pipe, the other end of the protective steel plate extends to the outer wall of the outer insulation pipe and abuts against the outer wall of the outer insulation pipe, and the end of the connecting pipe away from the working pipe is closed and provided with a drag connector.

[0009] Optionally, two adjacent protective steel plates are in contact with and fixedly connected to each other.

[0010] Optionally, the closed end of the connecting pipe has at least one drag-reducing slope.

[0011] Optionally, there are two or more drag reducing slopes, and the inclination angle of the drag reducing slopes is 45°.

[0012] Optionally, the axial center lines of the working tube and the connecting tube coincide with each other, and the drag connector is located on the axial center lines of the working tube and the connecting tube.

[0013] Optionally, the thickness of the protective steel plate is at least 20 mm.

[0014] Optionally, a towing head is further included, and the towing head is connected to the towing connecting head via a U-shaped buckle.

[0015] Optionally, the model of the U-shaped buckle is determined according to the pull-back force, and the pull-back force calculation formula is: Wherein, T is the pull-back force on the crossing pipe section; L is the crossing length; f h is the friction coefficient between the thermal pipeline section and the borehole wall; m is the weight of the drilling mud; G is the weight of the pipe; ω w is the weight of the pipeline per unit length when performing buoyancy control; D1 is the outer diameter of the thermal pipeline; K is the viscosity coefficient of the mud.

[0016] 3. Beneficial effects

[0017] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0018] The anti-falling joint structure used for directional drilling construction of finished hot water pipes can reduce soil resistance during the directional drilling back-pulling process, protect the insulation layer of the finished hot water pipes, and prevent the insulation joints from falling off during the back-pulling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of a joint structure for preventing a finished hot water pipe from falling off during directional drilling construction, proposed in an embodiment of the present invention;

[0020] 1. Inner core pipe; 2. External insulation pipe; 3. Connecting pipe; 3a. Resistance reduction slope; 4. Protective steel plate; 5. Drag connector. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described herein are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0022] It should be noted that when an element is referred to as being "fixed to", "disposed on", "fixed on" or "installed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. Further, when an element is considered to be "fixedly connected to" another element, the two may be fixed in a detachable connection manner or in a non-detachable connection manner, such as socketing, snap-on, one-piece fixation, welding, etc., which can be achieved in the prior art and will not be repeated here. When an element is perpendicular or approximately perpendicular to another element, it means that the ideal state of the two is vertical, but due to the influence of manufacturing and assembly, there may be a certain vertical error. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0024] The “first” and “second” involved in the present invention do not represent specific quantities and orders, but are merely used to distinguish names.

[0025] Combined with Figure 1 The present embodiment is a joint structure for preventing the finished hot water pipe from falling off during directional drilling construction, comprising a working pipe, an inner core pipe 1 and an outer insulation pipe 2, wherein the outer insulation pipe 2 is wrapped around the outer side of the inner core pipe 1; a connecting pipe 3 having the same diameter as the inner core pipe 1 and being welded and fixedly connected to the inner core pipe 1, wherein the connecting pipe 3 can be obtained by removing the outer insulation pipe 2 from the waste work, or by directly purchasing a pipe having the same diameter as the inner core pipe 1 as the connecting pipe, and no insulation layer is required on the outer side of the connecting pipe; a plurality of protective steel plates 4 are evenly distributed on the outer wall of the connecting pipe 3 along its circumferential direction, One end of the protective steel plate 4 is welded and fixedly connected to the connecting pipe 3, and the other end of the protective steel plate 4 extends to the outer wall of the external insulation pipe 2 and abuts against the outer wall of the external insulation pipe 2. The protective steel plate 4 and the external insulation pipe 2 are only abutted but not fixedly connected, and will not cause irreversible damage to the external insulation pipe 2. The protective steel plate 4 is in an inclined state at this time, which can guide the soil. The end of the connecting pipe 3 away from the working pipe is closed and provided with a drag connector 5, and also includes a drag head. The drag head is connected to the drag connector 5 by a U-shaped buckle.

[0026] During the directional dragging process, the joint structure for preventing the finished hot water pipeline from falling off during directional drilling construction can drag the working pipe to move in a directional manner through the connecting pipe 3, and on this basis, a plurality of the protective steel plates 4 can provide better protection for the outer insulation pipe 2 of the working pipe, preventing the outer insulation pipe 2 from falling off the inner core pipe 1. The above-mentioned protective effect is mainly achieved by preventing the end of the outer insulation pipe 2 from being subjected to force.

[0027] As an optional solution of the present invention, two adjacent protective steel plates 4 are in contact with each other and fixedly connected, so that there is no gap between the two adjacent protective steel plates 4, thereby preventing the soil from applying resistance to the end of the insulation pipe 2 through the gap. At this time, several of the protective steel plates 4 are connected in sequence to form a circular ring structure.

[0028] As an optional solution of the present invention, the closed end of the connecting pipe 3 has at least one drag reducing slope 3a, and the drag reducing slope 3a is obtained by welding a steel plate on the connecting pipe 3 without beveling at a certain angle, so as to prevent mud from entering the pipeline during the dragging process and ensure the connection strength with the dragging connector 5. At the same time, the drag reducing slope 3a reduces the resistance of the soil during the directional drilling back-dragging process. Specifically, two or more drag reducing slopes 3a are provided, and the inclination angle of the drag reducing slope 3a is 45°.

[0029] As an optional solution of the present invention, the axial center lines of the working tube and the connecting tube 3 coincide with each other, and the drag connector 5 is located on the axial center lines of the working tube and the connecting tube 3, so that when the working tube and the connecting tube 3 are dragged by the drag connector 5, the force at the connection position of the working tube and the connecting tube 3 is uniform, thereby avoiding excessive force on one side leading to connection failure.

[0030] As an optional solution of the present invention, the thickness of the protective steel plate 4 is at least 20 mm. Of course, the thickness of the protective steel plate 4 less than 20 mm can also meet the use requirements, but the protective steel plate 4 with a thickness of more than 20 mm is more stable when in use.

[0031] As an optional solution of the present invention, the model of the U-shaped buckle is determined according to the pull-back force, and the pull-back force calculation formula is: Wherein, T is the pull-back force KN on the crossing pipe section; L is the crossing length m; f h is the friction coefficient between the thermal pipeline section and the borehole wall, which is generally 0.1-0.3; m is the density of drilling mud kN / m 3 ; G is the weight of the pipeline in kN / m; ω w is the weight of the pipeline per unit length when performing buoyancy control kN / m; D1 is the outer diameter of the thermal pipeline; K is the viscosity coefficient of the mud kN / m2 When the mud viscosity is large, a larger value is taken, otherwise a smaller value is taken; the pull-back force is measured by the above pull-back force calculation formula and a corresponding U-shaped buckle is selected, so that the directional drilling pull-back process is safer and more reliable.

[0032] The present invention and its embodiments are described schematically above, and the description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it and designs a structural method and an embodiment similar to the technical solution without creativity without departing from the purpose of the invention, they shall all fall within the protection scope of the present invention.

Claims

1. A joint structure for preventing falling off during directional drilling of finished hot water pipes, characterized in that: include Working pipe, including inner core pipe and outer insulation pipe; A connecting pipe, which has the same diameter as the inner core pipe and is welded and fixedly connected to the inner core pipe; A plurality of protective steel plates are evenly distributed on the outer wall of the connecting pipe along its circumferential direction, one end of the protective steel plate is welded and fixedly connected to the connecting pipe, the other end of the protective steel plate extends to the outer wall of the outer insulation pipe and only abuts against the outer wall of the outer insulation pipe but is not fixedly connected, and the end of the connecting pipe away from the working pipe is closed and provided with a drag connector; Two adjacent protective steel plates are in contact with each other and are fixedly connected; The closed end of the connecting pipe has at least one resistance reducing inclined surface.

2. The anti-falling joint structure for directional drilling construction of finished hot water pipes according to claim 1 is characterized by: The drag reducing slopes are provided with two or more, and the inclination angle of the drag reducing slopes is 45°.

3. The anti-falling joint structure for directional drilling construction of finished hot water pipes according to claim 1 is characterized by: The axis lines of the working pipe and the connecting pipe coincide with each other, and the drag connector is located on the axis lines of the working pipe and the connecting pipe.

4. The anti-falling joint structure for directional drilling construction of finished hot water pipes according to claim 1 is characterized by: The thickness of the protective steel plate is at least 20 mm.

5. A joint structure for preventing falling off during directional drilling of finished hot water pipes according to any one of claims 1 to 4, characterized in that: It also includes a towing head, which is connected to the towing connecting head through a U-shaped buckle.

6. The anti-falling joint structure for directional drilling construction of finished hot water pipes according to claim 5 is characterized by: The model of the U-shaped buckle is determined according to the pull-back force, and the pull-back force calculation formula is: Wherein, T is the pull-back force on the crossing pipe section; L is the crossing length; f h is the friction coefficient between the thermal pipeline section and the borehole wall; m is the weight of the drilling mud; G is the weight of the pipe; ω w is the weight of the pipeline per unit length when performing buoyancy control; D1 is the outer diameter of the thermal pipeline; K is the viscosity coefficient of the mud.

Images