Linkage pressing type tong head reversing mechanism and power tongs

Abstract

The utility model belongs to the technical field of oil field wellhead operation equipment, and particularly relates to a linkage pressing type tong head reversing mechanism and a pair of power tongs. The pressing rod intermittently abuts against a pressing plate located at the end of the power piece, the guide piston slides in an inner cavity of the shell, the plug pin alternately slides in an arc groove of the tong head, and a linkage mechanism is formed by a connecting rod, the guide piston and the pressing rod, and the connecting rod is hinged to the lower end of the shell and slides on the outer side of the guide piston in a hinged mode. According to the utility model, the problem of inaccuracy or instability of bolt transposition is solved, the number of quick-wear parts is reduced, the operation is more convenient, the failure rate and the maintenance cost caused by a complex structure are reduced, and manual operation of the bolt or a reset knob is not needed, so that the operation time and the labor cost are obviously reduced, and the working efficiency is improved. The production efficiency of oil field wellhead operation is improved, and the actual requirement for diversification of the oil field wellhead operation is met.

Description

Technical Field

[0001] This utility model belongs to the technical field of oilfield wellhead operation equipment, specifically relating to a linkage pressing type pliers reversing mechanism and power pliers, which is suitable for threading and unthreading operations of tubular equipment such as tubing, casing, and drill pipe. Background Technology

[0002] In oilfield wellhead operations, power tongs are commonly used tools for threaded connections of tubular equipment, facilitating the threading and unthreading of tubular components such as tubing, casing, and drill pipe. To achieve multi-directional operation, improve work efficiency, and enhance mechanical adaptability, a tong head reversing mechanism is typically used to change the direction of the tong head's movement. Currently, there are two main types of power tong head reversing mechanisms: one uses a reset knob assembly to change the threading and unthreading direction, but this structure is costly to manufacture, has many vulnerable parts, and is prone to failure when torque increases, rendering the power tong unusable; the other uses a pin-type reversing mechanism to change the threading and unthreading direction by changing the position of the pin, but this structure requires manual insertion and removal of the pin, which is time-consuming, labor-intensive, and inefficient, and cannot meet the needs of remote or automated operations.

[0003] Existing technologies include research addressing the problems of current jaw head reversing mechanisms. For example, patent application CN101358511A – a lever-type jaw head steering mechanism for power jaws – uses the lever principle to achieve jaw head steering. While the structure is relatively simple, it still suffers from inconvenient operation and low reversing efficiency in practical applications. Other examples include patent applications CN103993844A – a rocker-type hydraulically controlled pin reversing and reset device for power jaws, and CN215672086U – a main jaw reversing mechanism for power jaws. Both achieve remote reversing control through hydraulically controlled pin reversing and reset devices. However, in practical applications, the rocker-type pin is easily affected by factors such as slope friction and the pin's own weight when climbing a hydraulically driven ramp, leading to inaccurate or unstable pin reversing. The guide rail-moving hydraulically controlled stop pin reset device suffers from problems such as the reset gear shaft extending out of the main jaw body, complex structure, and susceptibility to damage. Therefore, a new technical solution is needed to address these technical problems. Utility Model Content

[0004] The purpose of this utility model is to provide a linkage pressing type plier head reversing mechanism and a power plier to solve the problems mentioned in the background art, such as the complex structure, cumbersome operation, poor reversing stability of the current plier head steering mechanism, which makes it difficult to meet the actual needs of oilfield wellhead operations.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a linkage pressing type plier head reversing mechanism, comprising a housing and a power component. A set of pin assemblies is provided at each of the left and right ends of the housing. The pin assemblies slide within the housing via the power component. A pressure rod penetrating the top of the housing is provided at the upper part of the pin assembly. The top of the pressure rod intermittently abuts against a pressure plate located at the end of the power component. A guide piston sliding within the inner cavity of the housing is provided in the middle of the pin assembly. The guide piston, a connecting rod hinged to the lower end of the housing and simultaneously hinged to the outside of the guide piston, and the pressure rod form a linkage mechanism. A pin penetrating the bottom of the housing is provided at the lower part of the pin assembly. The lower ends of the two pins alternately slide within the arc groove of the plier head by the power component driving the pressure plate and the linkage mechanism to press down or lift, and by a spring fitted onto the upper end of the pin.

[0006] Furthermore, the power component includes a hydraulic cylinder or a pneumatic cylinder. The cylinder body of the hydraulic cylinder or pneumatic cylinder is fixed to the main structure of the clamp head. The piston rod end of the hydraulic cylinder or pneumatic cylinder is fixedly connected to the bottom of one end of the pressure plate. The bottom of the other end of the pressure plate is moved up and down by the piston rod of the hydraulic cylinder or pneumatic cylinder and intermittently abuts against the top of the pressure rod. The bottom end of the pressure rod passes through the outside of the top of the housing to the inner cavity of the housing and is fixed to the top of the guide piston.

[0007] Furthermore, the bottom end of the guide piston is fixedly connected to the upper end of the pin and simultaneously fixedly connected to the spring fitted on the upper end of the pin. The lower end of the spring is fixed to the bottom end of the inner cavity of the housing. The inner cavity of the housing is elastically slidably connected to the guide piston through the spring. The lower end of the pin passes through the inner cavity of the housing to the outside of the bottom end of the housing and slides in the arc groove of the pliers head.

[0008] Furthermore, a groove is formed on the outer surface of the guide piston, and a roller slides in the groove. The end of the roller is fixed to the inner side of the upper end of the connecting rod, and a pin is fixed to the inner side of the lower end of the connecting rod and hinged to the lower end of the housing. The connecting rod slides cyclically on the outer side of the guide piston along the annular structure of the groove through the roller. An upper concave point is eccentrically provided on the upper part of the groove, and a lower concave point is eccentrically provided on the lower part of the groove.

[0009] In addition to the above technical solutions, there are also power pliers with this linkage pressing type plier head reversing mechanism.

[0010] Compared with the prior art, the beneficial effects of this utility model are:

[0011] 1. This utility model utilizes the linkage between the guide piston, connecting rod, and pressure rod, as well as the elasticity of the spring, to allow the pins located at the left and right ends of the housing to slide alternately within the arc groove of the pliers head under the drive of the power component. This enables the pliers head to perform a reversing function. Compared with existing lever-type, pin-type, or rocker-type reversing mechanisms, this significantly improves the stability of reversing, effectively avoids the problems of inaccuracy or instability in pin repositioning, reduces the number of vulnerable parts, makes operation more convenient, and reduces the failure rate and maintenance costs caused by complex structure. The use of a power component drive method enables the pliers head reversing mechanism to have the function of remote operation, eliminating the need for manual operation of the pins or reset knob, thereby significantly reducing operation time and labor costs, improving the production efficiency of oilfield wellhead operations, and meeting the diverse practical needs of oilfield wellhead operations.

[0012] 2. This utility model uses a hydraulic cylinder or pneumatic cylinder to control the up-and-down movement of the pressure plate while intermittently contacting the pressure rod, ensuring the continuity and efficiency of power transmission, avoiding power loss and instability during transmission, thus making the maintenance of the entire clamp head reversing mechanism more convenient and reducing maintenance costs. The spring fitted on the upper end of the pin is set between the bottom end of the guide piston and the bottom end of the inner cavity of the housing, so that the pin can always maintain the preload under the action of the spring, improving the flexibility and accuracy of the reversing action. At the same time, it also realizes the buffering and stabilizing effect of the pin during the reversing process, avoiding damage or errors caused by impact, and further improving the service life of the entire mechanism.

[0013] 3. This utility model adopts a sliding fit between a ring-shaped groove and a roller to realize the relative movement between the connecting rod and the guide piston. While ensuring the continuity and stability of the connecting rod during the reversing process, it also effectively avoids damage or errors caused by excessive movement. At the same time, it reduces the frictional resistance during the movement, making the movement of the entire mechanism smoother and more efficient. By utilizing the eccentric setting of the upper and lower concave points, the connecting rod is precisely controlled by the change of the contact point between the roller and the groove under the action of the hydraulic cylinder or air cylinder driving the pressure plate to drive the pressure rod and linking the guide piston to move up and down. This achieves precise reversing of the pin in the arc groove of the clamp head, improves the production efficiency of oilfield wellhead operations, and meets the diverse practical needs of oilfield wellhead operations. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0015] Figure 2 for Figure 1 Schematic diagram of the connection structure between the middle housing and the pin assembly;

[0016] Figure 3 for Figure 1A structural diagram of a single-unit pin assembly (excluding connecting rods);

[0017] Figure 4 for Figure 1 Schematic diagram of the middle shell structure;

[0018] Figure 5 This is a top view of the connection between the reversing mechanism and the clamp head of this utility model;

[0019] Figure 6 This is a flowchart illustrating the reversing mechanism of this utility model.

[0020] The components are: 1. Housing; 101. Inner chamber; 2. Hydraulic cylinder or pneumatic cylinder; 201. Piston rod; 3. Pin assembly; 301. Pressure rod; 302. Guide piston; 303. Pin; 4. Pressure plate; 5. Spring; 6. Pliers head; 601. Arc groove; 7. Connecting rod; 8. Slide groove; 801. Upper concave point; 802. Lower concave point; 9. Roller; 10. Pin. Detailed Implementation

[0021] The following embodiments are used to further illustrate the content of this utility model, and do not limit the application of this utility model. Example 1:

[0022] Please see Figures 1-6 This embodiment provides a linkage pressing type plier head reversing mechanism, including a housing 1 and a hydraulic cylinder or air cylinder 2 for providing a power source. The cylinder body end of the hydraulic cylinder or air cylinder 2 is fixed to the main body structure of the plier head 6 (the functions and structures of conventional equipment such as the main body structure of the plier head are well known in the art, and the connection settings are also common knowledge, so they will not be described in detail here, nor are they shown in the accompanying drawings). Each of the left and right ends of the housing 1 is provided with a set of pin assemblies 3 for controlling the reversing of the plier head. The pin assemblies 3 slide in the housing 1 through the hydraulic cylinder or air cylinder 2, so that the bottom ends of the two sets of pin assemblies 3 can slide alternately in the arc groove 601 of the plier head 6, thereby realizing the reversing of the plier head 6;

[0023] The pin assembly 3 includes a pressure rod 301 disposed at the top and passing through the top of the housing 1, a guide piston 302 disposed in the middle and sliding in the inner cavity 101 of the housing 1, and a pin 303 disposed at the bottom and passing through the bottom of the housing 1. The top end of the pressure rod 301 intermittently abuts against the pressure plate 4 located at the end of the hydraulic cylinder or air cylinder 2. The bottom end of the pressure rod 301 passes through the outside of the top of the housing 1 to the inner cavity 101 of the housing 1 and is simultaneously fixed to the top end of the guide piston 302. The bottom end of the guide piston 302 is fixedly connected to the upper end of the pin 303 and simultaneously fixedly connected to the spring 5 fitted on the upper end of the pin 303. The lower end of the spring 5 is fixed to the bottom end of the inner cavity 101 of the housing 1. The inner cavity of the housing 1 is elastically slidably connected to the guide piston 302 through the spring 5. The lower end of the pin 303 passes through the inner cavity 101 of the housing 1 to the outside of the bottom end of the housing 1 and slides in the arc groove 601 of the pliers head 6.

[0024] One end of the pressure plate 4 is fixed to the piston rod end of the hydraulic cylinder or air cylinder 2, and the other end of the pressure plate 4 is moved up and down by the piston rod 201 of the hydraulic cylinder or air cylinder 2 and intermittently abuts against the top of the pressure rod 301.

[0025] The guide piston 302, the connecting rod 7 and the pressure rod 301, which are hinged to the lower end of the housing 1 and simultaneously hinged to slide on the outside of the guide piston 302, form a linkage mechanism;

[0026] A groove 8 for sliding the connecting rod 7 is provided on the outer surface of the guide piston 302. A roller 9 for driving the connecting rod 7 to move is slidably in the groove 8. The end of the roller 9 is fixed to the inner side of the upper end of the connecting rod 7. A pin 10 for hinge is fixed to the inner side of the lower end of the connecting rod 7 and is hinged to the lower end of the housing 1 through the pin 10.

[0027] The connecting rod 7 slides cyclically along the annular structure of the slide groove 8 via the roller 9 on the outside of the guide piston 302. The upper part of the slide groove 8 is eccentrically provided with an upper concave point 801 for the connecting rod 7 to slide to the upper end of the slide groove 8 for a limit, and the lower part of the slide groove 8 is eccentrically provided with a lower concave point 802 for the connecting rod 7 to slide to the lower end of the slide groove 8 for a limit.

[0028] The above configuration allows the two sets of pins 303 located at the lower part of the pin assembly 3 to slide alternately in the arc groove 601 of the pliers head 6 by driving the pressure plate 4 through the hydraulic cylinder or air cylinder 2 and driving the linkage mechanism to press down or lift up, and by utilizing the elastic reset effect of the spring, thereby realizing the reversing operation of the pliers head 6.

[0029] The working principle and usage process of this embodiment are as follows: Figures 1-6As shown, after the linkage pressing type plier head reversing mechanism is assembled, the operator installs the entire plier head reversing mechanism on the power plier (the functions and structures of conventional equipment such as power pliers are well known in the field, and the connection settings are also common knowledge, so they will not be explained here, nor are they shown in the attached drawings). The purpose is to allow the pins 303, which are located at the left and right ends of the housing 1, to slide alternately in the arc groove 601 of the plier head 6 under the drive of the hydraulic cylinder or the air cylinder 2, so that the plier head 6 has the function of reversing. This solves the problem of inaccuracy or instability of pin reversal, reduces the number of vulnerable parts, makes operation more convenient, reduces the failure rate and maintenance cost caused by the complex structure, and eliminates the need for manual operation of the pins or reset knob, thereby significantly reducing the operation time and labor costs, improving the production efficiency of oilfield wellhead operations, and meeting the diverse actual needs of oilfield wellhead operations.

[0030] Since the left side of the slide 8 is the channel for the connecting rod 7 to slide upward, and the right side is the channel for the connecting rod 7 to slide downward, the upper end of the connecting rod 7 first slides from the lower concave point 802 along the upward sliding channel to the upper concave point 801 through the roller 9, and then slides from the upper concave point 801 along the downward sliding channel to the lower concave point 802.

[0031] When the jaws of the power pliers need to be reversed, the operator first installs the two sets of pin assemblies 3 on the left and right ends of the housing 1 respectively. Then, the connecting rod 7 outside the guide piston 302 in the pin assembly 3 at the left end of the housing 1 is slid along the upward sliding channel of the roller 9 to the upper concave point 801 (the guide piston 302 is located in the lower part of the inner chamber 101, and the pressure rod 301 is in a low position). Meanwhile, the connecting rod 7 outside the guide piston 302 in the pin assembly 3 at the right end of the housing 1 is slid along the downward sliding channel of the roller 9 to the lower concave point 802 (the guide piston 302 is located in the upper part of the inner chamber 101, and the pressure rod 301 is in a high position). At this time, the lower end of the pin 303 in the pin assembly 3 at the left end of the housing 1 slides into the arc groove 601 of the jaw 6. At the same time, the lower end of the pin 303 in the pin assembly 3 at the right end of the housing 1 is in a retracted state (as shown in the image). Figure 6The first figure from top to bottom shows the initial state of the reversing mechanism. Since the hydraulic cylinder or pneumatic cylinder 2 is controlled by a control box or controller (the functions and structures of conventional equipment such as control boxes or controllers are well known in the art, and the connection settings are also common knowledge, so they will not be described in detail here, nor are they shown in the figures), when the reversing mechanism reverses, the operator remotely controls the piston rod 201 of the hydraulic cylinder or pneumatic cylinder 2 to retract (the initial state of the piston rod 201 is extended) through the control box or controller. The pressure plate 4 will move downward under the retraction of the piston rod 201, so that it first contacts the pressure rod 301 in the high position and drives the pressure rod 301 to compress the spring 5 downward until the pressure rod 301 in the high position is pressed down to the point where it meets the spring 5. When the pressure rod 301 is at the same height as the lower position, the retraction of the piston rod 201 stops, causing the guide piston 302 located at the upper part of the inner chamber 101 to slide from the upper part to the lower part of the inner chamber 101 under the pressure of the pressure rod 301. Meanwhile, the guide piston 302 located at the lower part of the inner chamber 101 remains stationary under the pressure of the pressure rod 301. Simultaneously, the connecting rod 7 at the left end of the housing 1 remains stationary at the upper concave point 801 or slides slightly to the right of the upper concave point 801, while the connecting rod 7 at the right end of the housing 1 slides along the upward sliding channel via the roller 9 to the upper concave point 801. At this time, the bottom ends of the pin 303 at the left end of the housing 1 and the pin 303 at the right end of the housing 1 are on the same horizontal plane (e.g., ...). Figure 6 (As shown in the second figure from top to bottom in the middle), then the piston rod 201 of the hydraulic cylinder or air cylinder 2 is extended remotely through the control box or controller, causing the pressure plate 4 to be lifted upward under the extension of the piston rod 201. This causes the connecting rod 7 at the left end of the housing 1 to slide from the upper concave point 801 to the lower concave point 802 under the combined action of its own weight and the elastic return of the spring 5. At this time, the guide piston 302 and the pressure rod 301 at the left end of the housing 1 will be lifted upward simultaneously under the linkage of the connecting rod 7, forcing the pin 303 at the left end of the housing 1 to enter the retracted state. Meanwhile, the connecting rod 7 at the right end of the housing 1 will remain stationary at the upper concave point 801. At this time, the guide piston 302 and the pressure rod 301 at the right end of the housing 1 will also remain stationary, forcing the lower end of the pin 303 at the right end of the housing 1 to slide into the arc groove 601 of the clamp head 6 (as shown in the figure below). Figure 6 (As shown in the third picture from the top), this completes the reversing operation of the clamp head 6, realizing the control of the upper and lower buckle directions. Example 2:

[0032] Please see Figures 1-6 As another objective of this utility model, a power pliers is provided, which is equipped with the above-mentioned linkage pressing type pliers head reversing mechanism. Therefore, the power pliers can obtain any of the beneficial effects of the linkage pressing type pliers head reversing mechanism described above, which will not be repeated here.

Claims

1. A linkage-pressing type plier head reversing mechanism, comprising a housing and a power component, characterized in that, Each of the left and right ends of the housing is provided with a set of pin assemblies. The pin assemblies slide within the housing via a power component. The upper part of the pin assembly is provided with a pressure rod that penetrates through the top of the housing. The top of the pressure rod intermittently abuts against a pressure plate located at the end of the power component. The middle part of the pin assembly is provided with a guide piston that slides within the inner cavity of the housing. The guide piston, a connecting rod hinged to the lower end of the housing and simultaneously hinged to slide outside the guide piston, and a pressure rod form a linkage mechanism. The lower part of the pin assembly is provided with a pin that penetrates through the bottom of the housing. The lower ends of the two pins slide alternately within the arc groove of the pliers head by the power component driving the pressure plate and driving the linkage mechanism to press down or lift up, as well as by the spring fitted on the upper end of the pin.

2. The linkage pressing type clamp head reversing mechanism according to claim 1, characterized in that, The power component includes a hydraulic cylinder or a pneumatic cylinder. The cylinder body of the hydraulic cylinder or pneumatic cylinder is fixed to the main structure of the clamp head, and the piston rod end of the hydraulic cylinder or pneumatic cylinder is fixedly connected to the bottom of one end of the pressure plate.

3. The linkage pressing type clamp head reversing mechanism according to claim 2, characterized in that, The bottom of the other end of the pressure plate is moved up and down by a piston rod of a hydraulic cylinder or pneumatic cylinder, and intermittently abuts against the top of the pressure rod.

4. The linkage pressing type clamp head reversing mechanism according to claim 3, characterized in that, The bottom end of the pressure rod passes from the outside of the top of the housing to the inner cavity of the housing and is simultaneously fixed to the top of the guide piston.

5. The linkage pressing type clamp head reversing mechanism according to claim 4, characterized in that, The bottom end of the guide piston is fixedly connected to the upper end of the pin and simultaneously fixedly connected to the spring. The lower end of the spring is fixed to the bottom end of the inner cavity of the housing. The inner cavity of the housing is elastically slidably connected to the guide piston through the spring.

6. The linkage pressing type plier head reversing mechanism according to claim 5, characterized in that, The lower end of the pin passes through the inner cavity of the housing to the outside of the bottom end of the housing and slides in the arc groove of the pliers head.

7. The linkage pressing type clamp head reversing mechanism according to claim 1, characterized in that, A groove is formed on the outer surface of the guide piston, and a roller slides in the groove. The end of the roller is fixed to the inner side of the upper end of the connecting rod, and a pin is fixed to the inner side of the lower end of the connecting rod and hinged to the lower end of the housing through the pin.

8. The linkage pressing type plier head reversing mechanism according to claim 7, characterized in that, The connecting rod slides cyclically along the annular structure of the slide groove on the outside of the guide piston via a roller.

9. A linkage pressing type plier head reversing mechanism according to claim 8, characterized in that, The upper part of the slide groove is eccentrically provided with an upper concave point, and the lower part of the slide groove is eccentrically provided with a lower concave point.

10. A power clamp, characterized in that, Including a linkage pressing type plier head reversing mechanism as described in any one of claims 1-9.

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