Novel loading device and method for stress-directed hydrogen induced cracking evaluation test

Abstract

The invention relates to a novel loading device for a stress-directed hydrogen induced cracking evaluation test and a method thereof, and the novel loading device for the stress-directed hydrogen induced cracking evaluation test is constructed by a basic frame, an inner fulcrum cushion block, a rotating wheel, a torsion wrench, a frame shaped like a Chinese character'ji ', a bending loading screw, a torsion loading screw and a ceramic rod. A defined torsion load is applied through a loading device, and shear strain is established; then applying a defined bending load through the loading device until the loading device reaches the total test strain; and putting the whole device into a solution containing a corrosive medium to carry out a stress corrosion test to obtain a corrosion result. According to the invention, the traditional four-point bending corrosion test can be realized, and the corrosion test under the complex stress condition of bending and torsion can also be realized, so that the test condition is closer to the working condition of the tested material, and the test result has more practical reference significance.

Description

Technical Field

[0001] The invention belongs to the technical field of steel pipe corrosion detection, in particular to a novel loading device and method for a stress-oriented hydrogen-induced cracking evaluation test. Background Art

[0002] The four-point bending test specifies the method for evaluating the cracking resistance of tensile stress carbon steel, low alloy steel and corrosion-resistant alloy materials in aqueous solutions containing H2S. The four-point bending loads the rectangular specimen to a specific deflection. After a period of constant deformation in an aqueous solution containing H2S, the failure / non-failure test result can be given. The four-point bending method specimen loading can produce uniform tensile stress on the convex outer surface of the specimen between the inner support points. From the inner support point to the outer support point, the stress drops linearly to zero. The standard specimen size is (115.0±1.3) mm long, (15.0±0.13) mm wide, and (5.0±0.13) mm thick.

[0003] The loading device of the traditional four-point bending stress corrosion test is to use a constant deflection fixture to bend the specimen at four points. Figure 1 As shown in the figure, the two ends of the specimen are supported by external fulcrums. By twisting the loading screw at the top of the device, a predetermined equal force is applied to the two inner fulcrums of the specimen. The magnitude of the applied force is fed back by measuring the deflection change of the specimen at four points of bending - the deflection change at the middle position of the specimen is measured using an appropriate deflectometer.

[0004] The following is the conversion method between elastic stress and specimen deflection: The axial elastic stress S of the convex outer surface of the specimen between the two supporting points is calculated by the following formula:

[0005] S=12Ety / (3H2-4A2)

[0006] Where: S - maximum tensile stress, in megapascals (MPa); E - elastic modulus, in megapascals (MPa); t - specimen thickness, in millimeters (mm); y - maximum deflection between external supports, in millimeters (mm); H - distance between external supports, in millimeters (mm); A - distance between internal supports, in millimeters (mm). The dimensions are usually selected so that A = H / 4.

[0007] However, the stress conditions of these materials during actual application may be very complicated. They may have to withstand both bending stress and shear stress caused by torsion, that is, complex alternating stress caused by the superposition of bending and torsion.

[0008] Therefore, people have tried to improve the above test scheme. Standard AMPPTM21451-2023 "Evaluation of the performance of carbon steel and low alloy steel against stress hydrogen induced cracking (SOHIC)" provides a new test scheme. The sketch and actual photos of the test device are as follows: Figure 2 Harm Figure 3 shown.

[0009] The test device is capable of applying superimposed loads of bending and torsion to the specimen. The total superimposed test stress is only exhibited within the internal support interval, while the torsion (shear) stress is exhibited over the entire specimen length between the external load points. All device components except the specimen should be strong enough and able to resist stress corrosion and hydrogen-induced cracking in the test environment. The adverse effects of electrochemical corrosion caused by contact between the specimen and the components on the test should be avoided. The nominal specimen size given in AMPPTM21451-2023 is 140mm long X15mm wide X5mm thick. The distance between the external torsion point and the external support fixing point is 100mm, and the spacing between the internal supports in the central part is 50mm. During the load application process: first, apply a defined torsional load (angular displacement / torsion angle) to establish shear strain; then, apply a defined bending load (bending displacement) until the four-point bending loading device reaches the total test strain (usually related to a percentage of the specified minimum yield strength-SMYS). Make the strain gauge (such as Figure 3 The strain gauge (as shown) is connected to the strain detector to detect the torsion and bending strain parameters and adjust them to appropriate values.

[0010] However, the above test device has the following shortcomings:

[0011] 1) Even if the frame thickness of the device is relatively large (greater than 30mm), the hollow torsion loading end is relatively weak. When the load is large, the frame rigidity may not be guaranteed;

[0012] 2) All screws and screw holes on the device are very thin. Due to repeated twisting wear, long-term stress and test corrosion, these screws and screw holes may fail quickly and become unusable;

[0013] 3) The positioning accuracy of the torsion member in contact with the specimen may be greatly affected during assembly and load application;

[0014] 4) The stability of the fulcrum inside the sphere is questionable;

[0015] 5) The specimen length requirement is special, which is not compatible with the standard length of traditional four-point bending specimens, and is not conducive to the unified batch standardization of specimen processing and test arrangements;

[0016] 6) AMPPTM21451-2023 recommends that the test device use a low-alloy material similar to the specimen, and coat each component with an inert anti-corrosion material to avoid the negative impact of electrochemical corrosion on the specimen, which carries a greater risk of failure. Because the device and the specimen need to be immersed in a corrosive solution for a long period of time, once the anti-corrosion material has extremely small local cracks or local wear damage, the entire anti-corrosion layer may quickly peel off, ultimately affecting the test results and the service life of the test device. Therefore, it is of great significance to study a new test device that can eliminate the impact of the above problems. Summary of the invention

[0017] The purpose of the present invention is to overcome the shortcomings of the prior art and propose a new loading device and method for stress-guided hydrogen-induced cracking evaluation test. The present invention can realize the traditional four-point bending corrosion test and can also realize the corrosion test under complex stress conditions of bending + torsion, so that the test conditions are closer to the working conditions of the test material, and the test results will have more practical reference significance.

[0018] The present invention solves the technical problem by adopting the following technical solutions:

[0019] A new loading device for stress-guided hydrogen-induced cracking evaluation test comprises a basic frame, an inner support pad, a rotating wheel, a torsion wrench, a giant-shaped frame, a bending loading screw, a torsion loading screw and a porcelain rod, wherein the basic frame comprises a bending loading part and a torsion loading part, the bending loading part is a gate-shaped frame, the torsion loading part comprises two cylinders and a column, one side of the two cylinders is respectively connected to the connecting legs of the gate-shaped frame, the other side of the gate-shaped frame is respectively connected to the columns, the connecting legs are provided with grooves facing the bending loading part, the torsion wrench is installed in the groove, the groove is provided with a through hole, the rotating wheel is connected to the torsion wrench through the through hole, one side of the rotating wheel is close to the connecting leg, and the other side faces the torsion loading part, the rotating wheel is provided with a giant-shaped frame facing the torsion loading part, and the opening of the giant-shaped frame faces the rotating wheel, The giant-shaped frame is installed between two cylinders, a through hole is provided in the middle of the giant-shaped frame, a through hole is provided in the rotating wheel, the through hole of the giant-shaped frame, the through hole of the rotating wheel and the through hole of the groove are coaxial, the torsion loading screw is connected to the torsion wrench through the through hole of the giant-shaped frame, the through hole of the rotating wheel and the through hole of the groove, the fixed leg of the door-shaped frame is provided with a sample groove, the torsion wrench is provided with a sample groove toward the bending loading part, the sample is installed in the basic frame through the sample groove of the fixed leg and the sample groove of the torque wrench, two semicircular grooves are provided at the bottom of the inner fulcrum pad, a porcelain rod is placed above the sample, the inner fulcrum pad is placed above the porcelain rod through the two semicircular grooves, a hemispherical surface is provided on the top of the inner fulcrum pad, the door-shaped frame is provided with a through hole, and the bending loading screw contacts the hemispherical surface on the top of the inner fulcrum pad through the through hole of the door-shaped frame.

[0020] Moreover, the giant-shaped frame is provided with two upper and lower protruding cylinders facing the rotating wheel.

[0021] Moreover, large spiral grooves are provided on the upper and lower surfaces of the rotating wheel.

[0022] Moreover, the torque wrench is provided with a through hole, the diameter of the through hole of the torque wrench is larger than the diameter of the through hole of the rotating wheel, and the diameter of the through hole of the rotating wheel is larger than the diameter of the torsion loading screw.

[0023] A loading method of a novel loading device for a stress-oriented hydrogen-induced cracking evaluation test comprises the following steps:

[0024] Step 1: Apply a defined torsional load to establish shear strain;

[0025] Step 2, applying the defined bending load until the loading device reaches the total test strain;

[0026] Step 3: Place the entire device in a solution containing a corrosive medium to carry out a stress corrosion test and obtain corrosion results.

[0027] Moreover, the specific implementation method of step 1 is: use a wrench to rotate the torsion loading screw clockwise, and the stepped end face in the middle of the torsion loading screw pushes the right side frame of the giant-shaped frame. Under the action of thrust and the restriction of the upper and lower cylindrical guide rails, the giant-shaped frame can only move to the left. The two small cylinders at the upper and lower ends of the left side of the giant-shaped frame are drawn into the large spiral groove of the rotating wheel. The rotating wheel constrained by the surrounding components can only deflect along its axis. The deflected rotating wheel will drive the torsion wrench 4 in contact with it to deflect axially at the same time. During the axial deflection process, the torsion wrench 4 will apply a torsion load to the sample clamped by it, thereby completing the application of the torsion load.

[0028] Moreover, the specific implementation method of step 2 is: the bending loading screw is rotated by a wrench, and the spherical surface at the bottom of the bending loading screw acts on the inner fulcrum pad, and the inner fulcrum pad applies load to the sample through the porcelain rod. The sample is strained under the fixation of the sample groove of the fixed leg and the sample groove of the torque wrench, thereby completing the application of the bending load.

[0029] The advantages and positive effects of the present invention are:

[0030] 1. The present invention constructs a new loading device for stress-guided hydrogen-induced cracking evaluation test through a basic frame, an inner support pad, a rotating wheel, a torsion wrench, a giant-shaped frame, a bending loading screw, a torsion loading screw and a porcelain rod. It can realize the traditional four-point bending corrosion test and the corrosion test under the complex stress conditions of bending + torsion, so that the test conditions are closer to the working conditions of the test material, and the test results will have more practical reference significance.

[0031] 2. All components except the sample and the porcelain rod of the present invention are made of nickel-based stainless steel or Ti alloy material, which has high material strength, good component rigidity, strong wear resistance and corrosion resistance, and can be cleaned by soaking in strong acid.

[0032] 3. The sizes of all screws and screw holes of the present invention have been significantly increased, making them more solid, stable, wear-resistant and durable to use. The end of the sample bending loading screw is spherical in design, which is convenient for adapting to the sample torsion loading process.

[0033] 4. The left end of the sample of the present invention is locked, and the torsion member in contact with the right end of the sample is locked at the same time. During the assembly and load application process, the positioning accuracy of the sample is high and lateral movement is not likely to occur;

[0034] 5. The porcelain rod of the present invention is used on the inner fulcrum, which is much more stable than the spherical inner fulcrum;

[0035] 6. The present invention adopts the standard specimen length of the traditional four-point bend, which is more conducive to the unified batch standardization of specimen processing and test arrangement;

[0036] 7. During each test of the present invention, the two ends of the sample other than the outer support point are insulated with a relatively high-strength polytetrafluoro film to properly eliminate the influence of electrochemical corrosion on the sample and ensure the validity of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the loading device of the traditional four-point bending stress corrosion test;

[0038] Figure 2 The schematic diagram of the superimposed load device for traditional bending and torsion;

[0039] Figure 3 Schematic diagram of the traditional bending and torsion superposition load device;

[0040] Figure 4 is an isometric view of the present invention;

[0041] Figure 5 It is the front view of the present invention;

[0042] Figure 6 It is an isometric perspective view of the present invention;

[0043] Figure 7 It is an isometric perspective view of the basic framework of the present invention;

[0044] Figure 8 It is an isometric perspective view of the inner fulcrum pad of the present invention;

[0045] Fig. 9 is an isometric perspective view of the rotating wheel of the present invention;

[0046] Fig.10 is an isometric perspective view of the torque wrench of the present invention;

[0047] Fig.11 It is an isometric perspective view of the giant frame of the present invention;

[0048] Fig.12 It is an isometric view of the bending loading screw of the present invention;

[0049] Fig.13 It is an isometric view of the torsion loading screw of the present invention;

[0050] Fig.14 It is an isometric view of the porcelain rod of the present invention;

[0051] Fig.15 It is an isometric view of the sample of the present invention.

[0052] Description of labels:

[0053] 1- Basic frame 1, inner support block 2, rotating wheel 3, torque wrench 4, "giant" shaped frame 5, bending loading screw 6, torsion loading screw 7, porcelain rod 8 and sample 9 DETAILED DESCRIPTION

[0054] The present invention is further described in detail below with reference to the accompanying drawings.

[0055] A new type of loading device for stress-oriented hydrogen-induced cracking evaluation test, such as Figures 4 to 15As shown, it includes a basic frame, an inner support pad, a rotating wheel, a torsion wrench, a giant-shaped frame, a bending loading screw, a torsion loading screw and a porcelain rod, wherein the basic frame includes a bending loading part and a torsion loading part, the bending loading part is a door-shaped frame, the torsion loading part includes two cylinders and a column, one side of the two cylinders is respectively connected to the connecting legs of the door-shaped frame, and the other side of the door-shaped frame is respectively connected to the column, the connecting legs are provided with grooves facing the bending loading part, the torsion wrench is installed in the groove, the groove is provided with a through hole, the rotating wheel is connected to the torsion wrench through the through hole, one side of the rotating wheel is close to the connecting leg, and the other side faces the torsion loading part, the rotating wheel is provided with a giant-shaped frame facing the torsion loading part, the opening of the giant-shaped frame faces the rotating wheel, and the giant-shaped frame is installed on the two A through hole is provided in the middle of the giant-shaped frame between the root cylinders, and a through hole is provided in the rotating wheel. The through hole of the giant-shaped frame, the through hole of the rotating wheel and the through hole of the groove are coaxial. The torsion loading screw is connected to the torsion wrench through the through hole of the giant-shaped frame, the through hole of the rotating wheel and the through hole of the groove. The fixed leg of the door-shaped frame is provided with a sample groove, and the torsion wrench is provided with a sample groove toward the bending loading part. The sample is installed in the basic frame through the sample groove of the fixed leg and the sample groove of the torque wrench. Two semicircular grooves are provided at the bottom of the inner fulcrum pad, a porcelain rod is placed above the sample, and the inner fulcrum pad is placed above the porcelain rod through the two semicircular grooves. A hemispherical surface is provided on the top of the inner fulcrum pad, and a through hole is provided in the door-shaped frame. The bending loading screw contacts the hemispherical surface on the top of the inner fulcrum pad through the through hole of the door-shaped frame.

[0056] The giant-shaped frame is provided with two upper and lower protruding cylinders toward the rotating wheel. The rotating wheel surface is provided with large spiral grooves. The torque wrench is provided with a through hole, the through hole diameter of the torque wrench is larger than the through hole diameter of the rotating wheel, and the through hole diameter of the rotating wheel is larger than the diameter of the torque loading screw.

[0057] All components except the sample and the porcelain rod of the present invention are made of nickel-based stainless steel or Ti alloy steel, which has the advantages of high material strength, good component rigidity, strong wear resistance and corrosion resistance, and can be cleaned by soaking in strong acid.

[0058] The insulated porcelain rod is used on the inner fulcrum, which is much more stable than the spherical inner fulcrum. In addition, during each test, the two ends of the sample other than the outer fulcrum are insulated with a high-strength polytetrafluoro film. This can properly eliminate the influence of electrochemical corrosion on the sample.

[0059] Use standard nominal specimen dimensions: 115mm long X15mm wide X5mm thick. The distance between the outer torsion point and the outer support point is 100mm, and the distance between the inner support points in the center is 50mm. Fix the device on the vise and apply the load: first, apply the defined torsion load (angular displacement / torsion angle) to establish the shear strain; then, apply the defined bending load (bending displacement) until the four-point bending loading device reaches the total test strain (usually related to the percentage of the specified minimum yield strength - SMYS). Connect the strain gauges attached to the specimen to the strain detector to detect the torsion and bending strain parameters and adjust them to appropriate values.

[0060] Finally, the entire device is placed in a solution containing a corrosive medium to carry out a stress corrosion test. This device can realize the traditional four-point bending corrosion test in the standard GB / T4157-2017, and can also realize the corrosion test under complex stress conditions of bending + torsion as in the standard AMPPTM21451-2023, making the test conditions closer to the working conditions of the test material, and the test results will have more practical reference significance.

[0061] A loading method of a novel loading device for a stress-oriented hydrogen-induced cracking evaluation test comprises the following steps:

[0062] Step 1: Apply a defined torsional load to establish shear strain.

[0063] The specific implementation method of step 1 is: use a wrench to rotate the torsion loading screw clockwise, and the stepped end face in the middle of the torsion loading screw pushes the right side frame of the giant-shaped frame. Under the action of thrust and the restriction of the upper and lower cylindrical guide rails, the giant-shaped frame can only move to the left. The two small cylinders at the upper and lower ends of the left side of the giant-shaped frame are drawn into the large spiral groove of the rotating wheel. The rotating wheel constrained by the surrounding components can only deflect along its axis. The deflected rotating wheel will drive the torsion wrench 4 in contact with it to deflect axially at the same time. During the axial deflection process, the torsion wrench 4 will apply a torsional load to the sample clamped by it to complete the application of the torsional load.

[0064] Step 2: Apply the defined bending load until the loading device reaches the total test strain.

[0065] The specific implementation method of step 2 is: rotate the bending loading screw through a wrench, the spherical surface at the bottom of the bending loading screw acts on the inner fulcrum pad, and the inner fulcrum pad applies load to the sample through the porcelain rod. The sample is strained under the fixation of the sample groove of the fixed leg and the sample groove of the torque wrench, completing the application of the bending load.

[0066] Step 3: Place the entire device in a solution containing a corrosive medium to carry out a stress corrosion test and obtain corrosion results.

[0067] According to the above-mentioned novel loading device and loading method for stress-oriented hydrogen-induced cracking evaluation test, the device is assembled and the samples are tested to verify the effect of the present invention.

[0068] The assembly method of the present invention is:

[0069] First, install the torque wrench on the base frame, then put the rotating wheel on the hexagonal adapter of the torque wrench (it is beneficial for the contact surface of the two components to have appropriate roughness, which can effectively limit the possible axial displacement of the torque wrench during the sample loading process). Next, install the giant-shaped frame (the end with the deeper guide groove facing upward) on the base frame. Insert the slender rod of the torque loading screw through the right through hole of the base frame, the through hole of the giant-shaped frame and the through hole of the rotating wheel, and screw the torque loading screw into the screw hole of the base frame for 2 to 5 turns, so that the two protruding cylinders on the giant-shaped frame just enter the large spiral groove of the rotating wheel, and also make the end of the torque wrench holding the sample in the appropriate working position. The inner diameter of the torque wrench is slightly larger than the inner diameter of the rotating wheel, and the inner diameter of the rotating wheel is slightly larger than the diameter of the slender rod of the torque loading screw, so as to ensure that the slender rod at the front end of the loading screw can pass through the circular hole in front of it without resistance, and also avoid axial movement of the torque wrench.

[0070] The specimen with insulation treatment at both ends is inserted into the torque wrench through the rectangular hole on the left side of the base frame to the appropriate position (about 8mm). The inner fulcrum pad is placed above the specimen. Two porcelain rods can be placed in the two semicircular grooves of the inner fulcrum pad respectively. The porcelain rods separate the specimen and the inner fulcrum pad, which plays a supporting and insulating role. Finally, the bending loading screw is screwed in through the screw hole at the top of the base frame, so that the spherical surface of the bending loading screw fits with the bottom of the hemispherical surface at the top of the inner fulcrum pad, and the entire test device is assembled.

[0071] The loading method of the present invention is:

[0072] Apply the defined torsion load. Use a wrench to rotate the torsion loading screw clockwise. The stepped end face in the middle of the torsion loading screw pushes the right side frame of the giant-shaped frame. The giant-shaped frame can only move to the left under the action of thrust and the restriction of the upper and lower cylindrical guide rails. The two small cylinders at the upper and lower ends of the left side of the giant-shaped frame are inserted into the large spiral groove of the runner. The runner constrained by the surrounding components can only deflect along its axis. The deflected runner will drive the torsion wrench in contact with it (constrained by the base frame) to deflect axially at the same time. During the axial deflection process, the torsion wrench will apply a torsion load to the specimen it is holding.

[0073] Then, a defined bending load (bending displacement) is applied until the total test strain (usually related to a percentage of the specified minimum yield strength - SMYS) is reached in this four-point bending loading device. The strain gauges attached to the specimen are connected to the strain detector to detect the torsion and bending strain parameters and adjust them to appropriate values.

[0074] Finally, the entire device is placed in a solution containing a corrosive medium to carry out a stress corrosion test. This device can realize the traditional four-point bending corrosion test in the standard GB / T4157-2017, and can also realize the corrosion test under complex stress conditions of bending + torsion as in the standard AMPPTM21451-2023, making the test conditions closer to the working conditions of the test material, and the test results will have more practical reference significance.

[0075] It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive. Therefore, the present invention includes but is not limited to the embodiments described in the specific implementation manner. Any other implementation manners derived by those skilled in the art based on the technical solution of the present invention also fall within the scope of protection of the present invention.

Claims

1. A new type of loading device for stress-oriented hydrogen-induced cracking evaluation test, characterized by: The invention comprises a basic frame, an inner support pad, a rotating wheel, a torsion wrench, a giant-shaped frame, a bending loading screw, a torsion loading screw and a porcelain rod, wherein the basic frame comprises a bending loading part and a torsion loading part, the bending loading part is a door-shaped frame, the torsion loading part comprises two cylinders and a column, one side of the two cylinders is respectively connected to the connecting legs of the door-shaped frame, the other side of the door-shaped frame is respectively connected to the column, the connecting legs are provided with grooves facing the bending loading part, the torsion wrench is installed in the groove, the groove is provided with a through hole, the rotating wheel is connected to the torsion wrench through the through hole, one side of the rotating wheel is close to the connecting legs, and the other side faces the torsion loading part, the rotating wheel is provided with a giant-shaped frame facing the torsion loading part, the opening of the giant-shaped frame faces the rotating wheel, and the giant-shaped frame is installed on the two A through hole is provided in the middle of the giant-shaped frame between the cylinders, and a through hole is provided in the rotating wheel. The through hole of the giant-shaped frame, the through hole of the rotating wheel and the through hole of the groove are coaxial. The torsion loading screw is connected to the torsion wrench through the through hole of the giant-shaped frame, the through hole of the rotating wheel and the through hole of the groove. The fixed legs of the door-shaped frame are provided with sample grooves, and the torsion wrench is provided with sample grooves toward the bending loading part. The sample is installed in the basic frame through the sample grooves of the fixed legs and the sample grooves of the torque wrench. Two semicircular grooves are provided at the bottom of the inner fulcrum pad, a porcelain rod is placed above the sample, and the inner fulcrum pad is placed above the porcelain rod through the two semicircular grooves. A hemispherical surface is provided on the top of the inner fulcrum pad, and a through hole is provided in the door-shaped frame. The bending loading screw contacts the hemispherical surface on the top of the inner fulcrum pad through the through hole of the door-shaped frame.

2. The novel loading device for stress-oriented hydrogen-induced cracking evaluation test according to claim 1 is characterized in that: The giant-shaped frame is provided with two upper and lower protruding cylinders facing the rotating wheel.

3. The novel loading device for stress-oriented hydrogen-induced cracking evaluation test according to claim 1 is characterized in that: Large spiral grooves are arranged on the upper and lower surfaces of the rotating wheel.

4. The novel loading device for stress-oriented hydrogen-induced cracking evaluation test according to claim 1 is characterized in that: The torque wrench is provided with a through hole, the diameter of the through hole of the torque wrench is larger than the diameter of the through hole of the rotating wheel, and the diameter of the through hole of the rotating wheel is larger than the diameter of the torsion loading screw.

5. A loading method for a novel loading device for stress-oriented hydrogen-induced cracking evaluation test according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Apply a defined torsional load to establish shear strain; Step 2, applying the defined bending load until the loading device reaches the total test strain; Step 3: Place the entire device in a solution containing a corrosive medium to carry out a stress corrosion test and obtain corrosion results.

6. The loading method of the novel loading device for stress-oriented hydrogen-induced cracking evaluation test according to claim 5 is characterized in that: The specific implementation method of step 1 is: use a wrench to rotate the torsion loading screw clockwise, and the stepped end face in the middle of the torsion loading screw pushes the right side frame of the giant-shaped frame. Under the action of thrust and the restriction of the upper and lower cylindrical guide rails, the giant-shaped frame can only move to the left. The two small cylinders at the upper and lower ends of the left side of the giant-shaped frame are drawn into the large spiral groove of the rotating wheel. The rotating wheel constrained by the surrounding components can only deflect along its axis. The deflected rotating wheel will drive the torsion wrench 4 in contact with it to deflect axially at the same time. During the axial deflection process, the torsion wrench 4 will apply a torsion load to the sample clamped by it to complete the application of the torsion load.

7. The loading method of the novel loading device for stress-oriented hydrogen-induced cracking evaluation test according to claim 5 is characterized by: The specific implementation method of step 2 is: rotate the bending loading screw through a wrench, the spherical surface at the bottom of the bending loading screw acts on the inner fulcrum pad, and the inner fulcrum pad applies load to the sample through the porcelain rod. The sample is strained under the fixation of the sample groove of the fixed leg and the sample groove of the torque wrench, thereby completing the application of the bending load.

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