A fatigue testing machine for testing the performance of oil drill pipes

Abstract

The present invention discloses a fatigue testing machine for testing the performance of oil drill pipes, and relates to the technical field of drill pipe testing. The present invention comprises: a base frame, the base frame is equipped with a first hydraulic push rod, the base frame is equipped with a strain sensor, the base frame is slidably connected with a sliding block, the sliding block is equipped with a first motor, and the output shaft of the first motor is equipped with a first clamp; a support ring, rotatably connected to the base frame, the support ring is equipped with a second clamp, and the second clamp is fixedly connected with a rotating shell; a fixed shell, rotatably connected to the rotating shell, and a damping medium is filled between the rotating shell and the fixed shell; an obstruction member, which is fixedly connected in the rotating shell. The present invention applies damping to the obstruction member through the damping medium, so that the drill pipe is subjected to dynamic torque, so as to simulate the motion loading state of the drill pipe in the formation during the actual working process, and avoid the conventional testing machine can only perform static load test on the drill pipe, resulting in poor representativeness of the test data.

Description

Technical Field

[0001] The invention relates to the technical field of drill pipe testing, in particular to a fatigue testing machine for testing the performance of a petroleum drill pipe. Background Art

[0002] Oil drill pipe is a key equipment in oil drilling operations. It is mainly composed of multiple connected steel pipes. It is used to lower the drill bit into the ground and transmit drilling torque and load as well as guide positioning. Since oil drill pipes have to withstand various complex mechanical loads during operation and are prone to fatigue failure, performance tests are required, mainly including: detecting whether the strength and rigidity of the drill pipe meet the design requirements, evaluating the stress and strain levels of the drill pipe under various working conditions, and predicting the fatigue life and reliability of the drill pipe. Fatigue testing machines are usually used to perform the above tests on drill pipes.

[0003] The working principle of the existing oil drill pipe fatigue testing machine is as follows: a servo hydraulic system is used for loading, a single axial, torsional and bending loads are applied to the drill pipe, and then the strain and other parameters of the drill pipe are monitored in real time through sensors, and the fatigue performance of the drill pipe is evaluated based on the load conditions and the obtained data. However, since the existing fatigue testing machine only applies a single type of load to the drill pipe, such as applying a single static torque to the drill pipe, and the drill pipe is subjected to a variety of loads during its work in the formation (and the load is continuously applied to the drill pipe in a changing state), the data obtained by the existing fatigue testing machine for the performance test of the drill pipe is inconsistent with the data of the drill pipe under actual working conditions, that is, the data obtained when the performance test of the drill pipe is inaccurate, which affects the normal evaluation of the drill pipe performance. Summary of the invention

[0004] In order to overcome the disadvantage that the existing fatigue testing machine performs single performance test on oil drill pipes, resulting in inaccurate test data of oil drill pipes, the present invention provides a fatigue testing machine for testing the performance of oil drill pipes.

[0005] The technical implementation scheme of the present invention is: a fatigue testing machine for testing the performance of oil drill pipes, comprising:

[0006] A base frame, wherein a first hydraulic push rod is installed on the base frame, a strain sensor is installed on the base frame for detecting stress changes of a drill rod, a sliding block is slidably connected to the base frame, the sliding block is fixedly connected to the telescopic end of the first hydraulic push rod, a first motor is installed on the sliding block, and a first fixture is installed on the output shaft of the first motor;

[0007] A support ring, rotatably connected to the base frame, the support ring is installed with a second clamp, the first clamp and the second clamp are both used to clamp the drill rod, and the second clamp is fixedly connected with a rotating shell;

[0008] A fixed shell is rotatably connected to the rotating shell, and a damping medium is filled between the rotating shell and the fixed shell;

[0009] A blocking member, fixedly connected to the rotating shell, wherein the blocking member is located between the rotating shell and the fixed shell;

[0010] The resistance-changing mechanism is arranged on the base frame and is used for changing the stress state of the obstructed member.

[0011] Preferably, the variable resistance mechanism includes:

[0012] A second motor is mounted on the base frame, and the base frame is fixedly connected to a mounting frame;

[0013] A rotating shaft, rotatably connected to the fixed shell;

[0014] A deflection member, fixedly connected to the rotating shaft, wherein the deflection member is located between the rotating shell and the fixed shell;

[0015] A first gear, fixedly connected to an output shaft of the second motor;

[0016] The second gear is fixedly connected to the rotating shaft, and the second gear is meshed with the first gear.

[0017] Preferably, the obstructing member and the deflecting member are both provided with protrusions arranged at intervals for obstructing the obstructing member.

[0018] Preferably, the protrusion on the obstructing member and the protrusion on the deflecting member are both provided with inclined surfaces for changing the resistance borne by the obstructing member.

[0019] Preferably, it also includes:

[0020] A second hydraulic push rod is mounted on the chassis;

[0021] A movable plate, fixedly connected to the telescopic end of the second hydraulic push rod;

[0022] A sliding member, slidably connected to the moving plate;

[0023] A squeezing roller, rotatably connected to the sliding member, the squeezing roller being used to squeeze the drill rod;

[0024] The transmission assembly is arranged on the mounting frame and is used to make the movable plate and the sliding member slide relative to each other.

[0025] Preferably, the outer side of the squeezing roller is wrapped with hard rubber to protect the drill rod.

[0026] Preferably, the transmission assembly includes:

[0027] The rotating rod and the rotating member are both rotatably connected to the mounting frame, the rotating rod is rotatably connected to the base frame, the rotating rod is connected to the output shaft of the second motor through a pulley belt transmission, and the rotating rod is connected to the rotating member through a bevel gear set;

[0028] An intermediate rod is rotatably connected to the sliding member and the rotating member, and a rotational connection point between the intermediate rod and the rotating member is located at an eccentric position on the rotating member.

[0029] Preferably, it also includes:

[0030] A knocking column, slidably connected to the mounting frame, the knocking column is used to impact the support ring, and an elastic element is fixedly connected between the knocking column and the mounting frame;

[0031] A limiting member, fixedly connected to the knocking column;

[0032] The limiting blocks are multiple and arranged at intervals, and are all fixedly connected to the rotating member. The limiting blocks are provided with an inclined surface, and the inclined surface is used to squeeze the limiting member.

[0033] Preferably, the axis of the striking column is perpendicular to the axis of the supporting ring, so as to apply radial impact force to the supporting ring.

[0034] Preferably, the vertical heights and slopes of the inclined surfaces on adjacent limiting blocks are different, so as to squeeze the limiting member to different degrees.

[0035] Compared with the prior art, the present invention has at least the following beneficial effects: the present invention applies damping to the obstruction by means of a damping medium, so that the drill pipe is subjected to dynamic torque, thereby simulating the movement and loading state of the drill pipe in the formation during actual working, thereby avoiding the situation that conventional testing machines can only perform static loading tests on the drill pipe, resulting in poor representativeness of the test data, thereby affecting the normal testing of the drill pipe performance; the damping medium is squeezed by means of the raised inclined surface on the obstruction and the raised inclined surface on the deflection member, so that the obstruction is subjected to a force opposite to its movement direction and a force parallel to its rotation axis, namely, the types of loading on the drill pipe are increased, so that the performance testing process is more in line with actual working conditions, thereby improving the accuracy and representativeness of the test data; by rotating The shaft drives the deflection member to rotate, thereby changing the distance between the deflection member and the obstruction member (the distance between adjacent inclined surfaces on the protrusions of the two), thereby changing the load borne by the obstruction member when passing through the deflection member, so that the load borne by the drill pipe is closer to the actual working condition, thereby improving the accuracy of the test data; the drill pipe is squeezed by the squeezing roller, so that the drill pipe is subjected to radial load and bends, so that the test force of the drill pipe is closer to the actual working condition, thereby performing a more complete test on the drill pipe; the support ring is impacted by the knocking column, thereby applying a radial impact force to the drill pipe, thereby simulating the force applied to the drill pipe by the formation during the actual working process of the drill pipe, thereby performing a more comprehensive performance test on the drill pipe, making the test data more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention;

[0037] Figure 2 It is a three-dimensional structural cross-sectional view of the chassis of the present invention;

[0038] Figure 3 It is a schematic diagram of the three-dimensional structure when the support ring and the second clamp of the present invention rotate together;

[0039] Figure 4 It is a three-dimensional structural cross-sectional view of the fixing shell and the mounting frame of the present invention;

[0040] Figure 5 It is a three-dimensional structural exploded diagram of the rotating shell and the parts thereon of the present invention;

[0041] Figure 6 It is a three-dimensional structural exploded diagram of the obstruction member, the rotation shaft and the deflection member of the present invention;

[0042] Figure 7 It is a cross-sectional view of the three-dimensional structure when the movable plate and the sliding member of the present invention slide relative to each other;

[0043] Figure 8 It is a schematic diagram of the three-dimensional structure of the rotating rod and the rotating member of the present invention when they rotate;

[0044] Fig. 9 For the present invention Figure 8 Enlarged view of the three-dimensional structure at A in the middle.

[0045] Names of the numbers in the figure: 101, drill rod, 1, base frame, 2, first hydraulic push rod, 3, sliding block, 4, first motor, 5, first clamp, 6, support ring, 7, second clamp, 8, rotating shell, 901, fixed shell, 902, obstruction member, 1001, second motor, 1002, mounting frame, 1004, rotating shaft, 1005, deflection member, 1006, first gear, 1007, second gear, 1101, second hydraulic push rod, 1102, moving plate, 1103, sliding member, 1104, squeezing roller, 1201, rotating rod, 1202, rotating member, 1203, intermediate rod, 1301, knocking column, 1302, elastic element, 1303, limiting member, 1304, limiting block. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] like Figure 1-Figure 5 As shown, a fatigue testing machine for oil drill pipe performance testing is proposed to solve the problem that the existing fatigue testing machine performs a single performance test on the oil drill pipe, resulting in inaccurate test data of the oil drill pipe, including: a base frame 1, the base frame 1 is equipped with a first hydraulic push rod 2, the base frame 1 is equipped with a strain sensor for detecting the stress change of the drill pipe 101, the base frame 1 is slidably connected with a sliding block 3, the sliding block 3 is fixedly connected to the telescopic end of the first hydraulic push rod 2, the sliding block 3 is equipped with a first motor 4, the output shaft of the first motor 4 is equipped with a first A clamp 5; a support ring 6, rotatably connected to the base frame 1, the support ring 6 is equipped with a second clamp 7, the first clamp 5 and the second clamp 7 are both used to clamp the drill rod 101, and the second clamp 7 is fixedly connected to a rotating shell 8; a fixed shell 901, rotatably connected to the rotating shell 8, and a damping medium is filled between the rotating shell 8 and the fixed shell 901; an obstruction 902, fixedly connected to the rotating shell 8, and the obstruction 902 is located between the rotating shell 8 and the fixed shell 901; a variable resistance mechanism, arranged on the base frame 1, for changing the force state of the obstruction 902.

[0048] In the above scheme, the base frame 1 is welded by steel sections, the first hydraulic push rod 2 is connected to the external hydraulic system, the strain sensor, the external hydraulic system and the first motor 4 are all connected to the external control center, which is used to read the load condition of the first motor 4 during the test (that is, to read the load condition of the drill rod 101, so as to record the changes of its own performance-related parameters), the first clamp 5 and the second clamp 7 are both existing chuck mechanisms, and their detailed working principles are not described in detail here. The damping medium between the rotating shell 8 and the fixed shell 901 The hydraulic oil is used. When in use, the drill rod 101 is transferred to the second clamp 7 by using a hoisting device, and the right end of the drill rod 101 is clamped and fixed by the second clamp 7. Then, the sliding block 3 is slid to the right along the base frame 1 by using the first hydraulic push rod 2 until the first clamp 5 can clamp the drill rod 101 and then stop moving. Then, the left end of the drill rod 101 is clamped and fixed by using the first clamp 5, and then the strain sensor is installed at the joint of the drill rod 101. After completing the above actions, the output shaft of the first motor 4 is used to drive the first clamp 5 to rotate counterclockwise (such as Figure 2 Taking the left viewing direction as an example), the first clamp 5 drives the drill rod 101 to rotate counterclockwise, and the drill rod 101 drives the second clamp 7 to rotate counterclockwise. The second clamp 7 drives the obstruction 902 to rotate counterclockwise by driving the rotating shell 8. The rotating shell 8 and the fixed shell 901 rotate relatively, and the obstruction 902 starts to move in the fixed shell 901. During the process, the hydraulic oil applies damping to the obstruction 902, so that the drill rod 101 is subjected to dynamic torque, so as to simulate the movement and loading state of the drill rod 101 in the formation during actual working process (the strain sensor records the strain of the drill rod 101 due to loading and uploads it to the control center), so as to avoid the conventional testing machine can only perform static load test on the drill rod 101, resulting in poor representativeness of the test data, thereby affecting the normal test of the performance of the drill rod 101.

[0049] like Figure 2-Figure 6 As shown, the variable resistance mechanism includes: a second motor 1001, mounted on a base frame 1, and the base frame 1 is fixedly connected to a mounting frame 1002; a rotating shaft 1004, rotatably connected to a fixed shell 901; a deflection member 1005, fixedly connected to the rotating shaft 1004, the deflection member 1005 is located between the rotating shell 8 and the fixed shell 901, the obstructed member 902 and the deflection member 1005 are both provided with protrusions arranged at intervals, for obstructing the obstructed member 902, the protrusions on the obstructed member 902 and the protrusions on the deflection member 1005 are both provided with inclined surfaces, for changing the resistance borne by the obstructed member 902; a first gear 1006, fixedly connected to the output shaft of the second motor 1001; a second gear 1007, fixedly connected to the rotating shaft 1004, the second gear 1007 is meshed with the first gear 1006.

[0050] In the above scheme, the second motor 1001 is connected to the external control center, the right side of the protrusion on the blocking member 902 is an inclined surface, and the left side of the protrusion on the deflection member 1005 is an inclined surface, and the inclined surface gradually tilts to the left from front to back (such as Figure 6 Taking the direction shown as an example), during the counterclockwise rotation of the obstruction 902, the obstruction 902 squeezes the hydraulic oil in the fixed shell 901, and the hydraulic oil has a tendency to move with the obstruction 902. When the obstruction 902 rotates counterclockwise to the area where the protrusion thereon is adjacent to the protrusion on the deflection member 1005, the hydraulic oil is squeezed by the two inclined surfaces and begins to apply a reaction force to the two protrusions, so that the obstruction 902 is subjected to a force opposite to its movement direction and a force parallel to its rotation axis, that is, the load types of the drill pipe 101 are increased, so that the performance test process is more in line with the actual working conditions, thereby improving the accuracy and representativeness of the test data.

[0051] After the obstruction 902 passes through the deflection member 1005, the "axial force" on the obstruction 902 disappears, and a pulse axial force is applied to the drill rod 101, thereby simulating the force (axial force) change caused by different formation resistances during the operation of the drill rod 101, increasing the types of loads applied to the drill rod 101, and thus performing a more complete test on the drill rod 101.

[0052] If the load on the drill rod 101 needs to be increased, the output shaft of the second motor 1001 is used to drive the first gear 1006 to rotate clockwise (eg Figure 4 Taking the left-view direction as an example, when the load on the drill rod 101 needs to be reduced, the output shaft of the second motor 1001 can be reversed), the first gear 1006 drives the second gear 1007 to rotate counterclockwise, and the second gear 1007 drives the deflection member 1005 to rotate counterclockwise through the rotating shaft 1004, thereby shortening the distance between the deflection member 1005 and the obstruction member 902 (the minimum distance between adjacent inclined surfaces on the protrusions of the two), thereby increasing the load borne by the obstruction member 902 when passing through the deflection member 1005, so that the load acting on the drill rod 101 matches the resistance applied to it by different formations, making the test results more comprehensive.

[0053] like Figure 3 and Figure 7 As shown, it also includes: a second hydraulic push rod 1101, installed on the base frame 1; a moving plate 1102, fixedly connected to the telescopic end of the second hydraulic push rod 1101; a sliding member 1103, slidably connected to the moving plate 1102; a squeezing roller 1104, rotatably connected to the sliding member 1103, the squeezing roller 1104 is used to squeeze the drill rod 101, and the outer side of the squeezing roller 1104 is wrapped with hard rubber to protect the drill rod 101; a transmission assembly, arranged on the mounting frame 1002, used to make the moving plate 1102 and the sliding member 1103 slide relative to each other.

[0054] In the above scheme, the second hydraulic push rod 1101 is connected to the external hydraulic system, and the hard rubber on the squeezing roller 1104 is used to protect the drill rod 101 when squeezing the drill rod 101 to prevent excessive squeezing force from causing depression (indentation) on the surface of the drill rod 101. The telescopic end of the second hydraulic push rod 1101 drives the movable plate 1102 to move downward, and the movable plate 1102 drives the squeezing roller 1104 to move downward together through the sliding member 1103. After the squeezing roller 1104 contacts the drill rod 101, the squeezing roller 1104 starts to apply pressure to the drill rod 101, so that the drill rod 101 is subjected to radial load, and the drill rod 101 is bent and deformed, so that the test force applied to the drill rod 101 is closer to the actual working condition, further increasing the scope of application of the present application, so that the data obtained by testing the drill rod 101 is more accurate.

[0055] like Figure 3 and Figure 7 and Figure 8 As shown, the transmission assembly includes: a rotating rod 1201 and a rotating member 1202, both of which are rotatably connected to the mounting frame 1002, the rotating rod 1201 is rotatably connected to the base frame 1, the rotating rod 1201 is connected to the output shaft of the second motor 1001 through a pulley belt transmission, and the rotating rod 1201 and the rotating member 1202 are connected through a bevel gear set; an intermediate rod 1203 is rotatably connected to the sliding member 1103 and the rotating member 1202, and the rotation connection between the intermediate rod 1203 and the rotating member 1202 is located at an eccentric position on the rotating member 1202.

[0056] In the above scheme, the bevel gear set is composed of a first bevel gear and a second bevel gear that mesh with each other, the first bevel gear is fixedly connected to the rotating rod 1201, and the second bevel gear is fixedly connected to the rotating member 1202. When the output shaft of the second motor 1001 drives the first gear 1006 to rotate clockwise, the output shaft of the second motor 1001 transmits torque to the rotating rod 1201 through the pulley belt, and the rotating rod 1201 transmits torque to the rotating member 1202 through the bevel gear set, and the rotating member 1202 starts to rotate counterclockwise (such as Figure 8 Taking the top view as an example), the rotating member 1202 drives the middle rod 1203 to start moving to the left, and the middle rod 1203 drives the squeezing roller 1104 to move to the left together through the sliding member 1103, thereby changing the position where the squeezing roller 1104 squeezes the drill rod 101, thereby changing the magnitude of the bending moment at the joint of the drill rod 101, thereby simulating the force change at the joint of the drill rod 101 during the drilling process, thereby improving the accuracy of the performance test of the drill rod 101.

[0057] like Figure 8 and Fig. 9As shown, it also includes: a knocking column 1301, which is slidably connected to the mounting frame 1002, the knocking column 1301 is used to impact the support ring 6, the axis of the knocking column 1301 is perpendicular to the axis of the support ring 6, and is used to apply radial impact force to the support ring 6, and an elastic element 1302 is fixedly connected between the knocking column 1301 and the mounting frame 1002; a limiting member 1303, which is fixedly connected to the knocking column 1301; a plurality of limiting blocks 1304, which are arranged at intervals and are all fixedly connected to the rotating member 1202, and the limiting blocks 1304 are provided with an inclined surface, which is used to squeeze the limiting member 1303, and the vertical heights and slopes of the inclined surfaces on adjacent limiting blocks 1304 are different, which are used to squeeze the limiting member 1303 to different degrees.

[0058] In the above scheme, the elastic element 1302 is a tension spring, which is used to apply tension to the knocking column 1301. The limit blocks 1304 are circumferentially unequally distributed, which are used to change the frequency of the knocking column 1301 impacting the support ring 6. The limit block 1304 is a triangular prism, and its edges are rounded. The cross section of the limit block 1304 is a right triangle, and the inclined surface on the limit block 1304 gradually tilts downward in a counterclockwise direction from top to bottom (such as Fig. 9 Taking the top view as an example), during the counterclockwise rotation of the rotating member 1202, the rotating member 1202 drives the limit block 1304 to rotate counterclockwise together. When the limit block 1304 rotates counterclockwise until it contacts the limit member 1303, as the rotating member 1202 continues to rotate counterclockwise, the inclined surface on the limit block 1304 pushes the limit member 1303 upward, and the limit member 1303 drives the knocking column 1301 to move upward together. The knocking column 1301 and the mounting bracket 1002 slide relative to each other, and the elastic element 1302 is stretched, and as the rotating member 1202 continues to rotate counterclockwise, after the inclined surface on the limit block 1304 is separated from the limit member 1303, the knocking column 1301 is quickly reset under the tension of the elastic element 1302, and impacts the support ring 6, thereby applying a radial impact force to the drill rod 101, and then simulating the force applied to the drill rod 101 by the formation during the actual working process of the drill rod 101, so as to conduct a more comprehensive performance test on the drill rod 101, making the test data more accurate.

[0059] The present invention encompasses any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the above preferred embodiments of the present invention, and those skilled in the art can fully understand the present invention without the description of these details.

[0060] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A fatigue testing machine for testing the performance of oil drill pipes, characterized in that: Included are: A base frame (1), the base frame (1) being equipped with a first hydraulic push rod (2), the base frame (1) being equipped with a strain sensor for detecting stress changes of a drill rod (101), the base frame (1) being slidably connected with a sliding block (3), the sliding block (3) being fixedly connected to the telescopic end of the first hydraulic push rod (2), the sliding block (3) being equipped with a first motor (4), and the output shaft of the first motor (4) being equipped with a first clamp (5); A support ring (6) is rotatably connected to the base frame (1); the support ring (6) is provided with a second clamp (7); the first clamp (5) and the second clamp (7) are both used to clamp the drill rod (101); the second clamp (7) is fixedly connected to a rotating shell (8); A fixed shell (901) is rotatably connected to the rotating shell (8), and a damping medium is filled between the rotating shell (8) and the fixed shell (901); A blocking member (902) is fixedly connected inside the rotating shell (8), and the blocking member (902) is located between the rotating shell (8) and the fixed shell (901); A variable resistance mechanism, arranged on the base frame (1) and used to change the force state of the obstructed member (902); The variable resistance mechanism comprises: A second motor (1001) is mounted on the base frame (1), and the base frame (1) is fixedly connected to a mounting frame (1002); A rotating shaft (1004) rotatably connected to the fixed shell (901); A deflection member (1005) fixedly connected to the rotating shaft (1004), the deflection member (1005) being located between the rotating shell (8) and the fixed shell (901); A first gear (1006) fixedly connected to an output shaft of the second motor (1001); A second gear (1007) is fixedly connected to the rotating shaft (1004), and the second gear (1007) is meshed with the first gear (1006); The obstructing member (902) and the deflecting member (1005) are both provided with protrusions arranged at intervals, which are used to obstruct the obstructing member (902); The protrusion on the obstructing member (902) and the protrusion on the deflecting member (1005) are both provided with inclined surfaces, which are used to change the resistance borne by the obstructing member (902).

2. The fatigue testing machine for testing the performance of oil drill pipe according to claim 1, characterized in that: Also included are: A second hydraulic push rod (1101) is mounted on the base frame (1); A movable plate (1102) fixedly connected to the telescopic end of the second hydraulic push rod (1101); A sliding member (1103) slidably connected to the moving plate (1102); A squeezing roller (1104) rotatably connected to the sliding member (1103), the squeezing roller (1104) being used to squeeze the drill rod (101); A transmission assembly is arranged on the mounting frame (1002) and is used to enable the movable plate (1102) and the sliding member (1103) to slide relative to each other.

3. A fatigue testing machine for testing the performance of oil drill pipes according to claim 2, characterized in that: The outside of the squeezing roller (1104) is wrapped with hard rubber, which is used to protect the drill rod (101).

4. The fatigue testing machine for testing the performance of oil drill pipe according to claim 2, characterized in that: The transmission assembly comprises: The rotating rod (1201) and the rotating member (1202) are both rotatably connected to the mounting frame (1002); the rotating rod (1201) is rotatably connected to the base frame (1); the rotating rod (1201) is connected to the output shaft of the second motor (1001) via a pulley belt transmission; and the rotating rod (1201) and the rotating member (1202) are connected via a bevel gear set; An intermediate rod (1203) is rotatably connected to the sliding member (1103) and the rotating member (1202), and a rotationally connected portion between the intermediate rod (1203) and the rotating member (1202) is located at an eccentric portion of the rotating member (1202).

5. The fatigue testing machine for testing the performance of oil drill pipe according to claim 4, characterized in that: Also included are: A knocking column (1301) is slidably connected to the mounting frame (1002), the knocking column (1301) is used to impact the support ring (6), and an elastic element (1302) is fixedly connected between the knocking column (1301) and the mounting frame (1002); A limiting member (1303) fixedly connected to the knocking column (1301); The limiting blocks (1304) are multiple and arranged at intervals, and are all fixedly connected to the rotating member (1202). The limiting blocks (1304) are provided with an inclined surface, and the inclined surface is used to press the limiting member (1303).

6. A fatigue testing machine for testing the performance of oil drill pipes according to claim 5, characterized in that: The axis of the striking column (1301) is perpendicular to the axis of the support ring (6), and is used to apply a radial impact force to the support ring (6).

7. The fatigue testing machine for testing the performance of oil drill pipe according to claim 5, characterized in that: The vertical heights and slopes of the inclined surfaces on adjacent limiting blocks (1304) are different, and are used to squeeze the limiting member (1303) to different degrees.

Images