29 results about "Fracture testing" patented technology

A deep engineering hard rock true triaxial dynamic disturbance aging fracture testing device belongs to the technical field of rock mechanics tests and comprises a counter-force frame, a pressure chamber and six main stress linear disturbance actuators. The main stress linear disturbance actuator comprises a linear disturbance motor and a main stress hydraulic cylinder; the linear disturbance motor is coaxially and fixedly installed at the outer end of a cylinder barrel of the main stress hydraulic cylinder, a dowel bar is arranged in a central hole channel of a piston rod of the main stress hydraulic cylinder, and a power output shaft of the linear disturbance motor is coaxially and fixedly connected with the dowel bar. According to the utility model, the matching form of a traditional dynamic actuator and a hydraulic oil source is abandoned, the linear motor is introduced into the true triaxial test equipment as a power disturbance source, the long-time dynamic disturbance structure of the true triaxial test equipment is simplified, and the energy consumption of the equipment is greatly reduced after the linear motor is used as the power disturbance source; the maintenance process is simpler, the maintenance cost is greatly reduced, the installation and debugging processes of the linear motor are more time-saving and labor-saving, and no extra floor area is needed.

The present invention provides a glass article having excellent mechanical strength. In particular, the present invention enables the hardness of the glass article to be predicted from the composition of the glass article, thereby reducing the time and cost associated with fracture testing, while also minimizing variables caused by the measurer or measurement environment, and thus provides a glass article with excellent reliability.

The application provides a high-low temperature composite environment sensitive fracture test system, which comprises a fracture testing machine, a high-low temperature composite salt spray test box and a main control cabinet; the test cavity of the high-low temperature composite salt spray test box is arranged in the environment sensitive fracture testing machine; a test piece is in the test cavity of the high-low temperature composite salt spray test box, a high-low temperature alternating corrosion environment is realized through a wet heat module, a low temperature module and a spraying device; a salt spray, a wet heat, a drying and a low temperature test section are set through a control system, the time and the cycle number of each test section are adjusted, a high-low temperature composite salt spray environment is formed, and the environment sensitive fracture test under a multi-factor coupling environment can be realized in cooperation with the environment sensitive fracture testing machine. The application has a flexible structure, a large adjustable range, high test efficiency, saves test space, can simulate the real service environment according to the service environment of the material test piece under different working conditions, adjust the environment test parameters, simulate the real service environment, and multi-levelly examine the environment sensitive fracture performance of the material.

The invention relates to a method for testing a fracture track of a metal material under a multi-field coupling effect. The method comprises the steps of sample preparation, high-temperature speckle preparation, sample loading, strain field acquisition, fracture morphology observation, data processing and fracture model establishment. By constructing a new fracture test method under the action of multi-field coupling, the problems of lack of physical field coupling factors, non-uniform test systems, limitation of fracture models and the like at present are effectively solved. A coupling loading test system capable of synchronously applying complex stress, high strain rate and transient high temperature is established, and real simulation of the multi-physical field coupling effect under the actual disaster working condition is achieved; a metal material fracture test system with universality and comparability is formed; key data support is provided for building a fracture model comprehensively considering the stress three-dimensional degree, the strain rate effect and temperature softening, the accuracy and reliability of fracture track prediction of the steel structure under the extreme disaster are remarkably improved, and an important basis is provided for engineering disaster resistance design and safety evaluation.

The utility model discloses a protective structure for a digital display type ceramic tile fracture modulus tester, and relates to the technical field of digital display type ceramic tile fracture modulus testers, the protective structure for the digital display type ceramic tile fracture modulus tester comprises a base, a protective assembly is arranged outside the base, a supporting assembly is arranged at the upper end of the base, and the protective assembly is arranged at the lower end of the base. The number of the supporting assemblies is two, a downward pressing shaft is arranged above the position between the two supporting assemblies, a downward pressing assembly is arranged above the downward pressing shaft, a display module is arranged at the upper end of the downward pressing assembly, a mounting frame is arranged between the rear end of the display module and the rear end of the base, and the protection assembly comprises an arc cover and a side protection cover. According to the scheme, the problems that an existing ceramic tile fracture modulus tester is short of protection outside, when ceramic is fractured, the ceramic is prone to splashing and hurting people, and the safety is poor are solved.

The utility model relates to the technical field of aluminum alloy bridges, in particular to an anti-fracture testing device for an aluminum alloy bridge, which overcomes the defect of lack of testing in the prior art and comprises a detection chamber, a lifter is fixedly mounted in the detection chamber, and a supporting plate is arranged at the output end of the lifter. A rack is arranged above the supporting plate, a gear is arranged in the detection chamber, the rack and the gear are mutually meshed and connected, a protective door is arranged on the right side of the gear, a first air cylinder is fixedly installed above the supporting plate, a guide rail is arranged above the supporting plate, a simulation group is arranged above the guide rail, and a second air cylinder is fixedly installed above the simulation group. A sprayer is rotatably connected to the upper portion of the simulation set, the right side of the simulation set is connected with the air rod end of a first air cylinder, a supporting frame is fixedly installed in the detection chamber, and the device has the advantages of being high in practicability and capable of achieving automatic detection.

A needle tester and a needle testing method, relating to the technical field of needle testing, including a bracket, and further including: a fixed table, arranged on the bracket and used for fixing the needle a to be tested; and a rotating component, arranged on the bracket, and when the rotating component rotates, it provides a swinging arc force for the needle a to be tested. The beneficial effects of the present invention are: a professional tester is designed, which can accurately measure the needle to be tested, so that the acting force for testing the needle is always in a stable position, and the force simulation is more accurate; the tester has multiple functions and can perform resilience testing, bending fatigue testing, anti-bending angle testing and fracture testing.

This invention discloses a 60-80mm thick high-strength and high-toughness 980MPa steel plate, comprising the following chemical composition by mass percentage (wt%): C: 0.06-0.08, Si: 0.20-0.25, Mn: 0.60-0.70, P≤0.010, S≤0.002, Ni: 4.6-4.8, Cr: 0.5-0.6, Mo: 0.40-0.50, V: 0.05-0.06, with the remainder being Fe. After tempering and quenching treatment, its microstructure consists of tempered sorbite with a small amount of retained austenite. Its yield strength is 840–920 MPa, tensile strength is 940–1000 MPa, elongation at break is ≥16%, reduction of area is ≥50%, impact energy at -84℃ is ≥250 J, shear area ratio is ≥90%, impact energy at -100℃ is ≥200 J, shear area ratio is ≥80%. After fracture testing, the fracture surface is fibrous, without white spots, bright lines, or penetrating cracks. It exhibits excellent overall performance, fully meeting the quality requirements for high-strength and high-toughness 980 MPa steel plates.

The invention is applicable to the field of testing mechanisms, and provides a ceramic fiber paper fracture testing mechanism which comprises a feeding channel, a receiving channel and a base plate, a rectangular gap matched with the base plate is arranged between the feeding channel and the receiving channel, and the feeding channel, the receiving channel and the base plate are fixedly arranged respectively. And a round paper sheet conveying mechanism is arranged between the feeding channel and the receiving channel. When the device is used, the edge of a round aluminum silicate fiber paper sheet can be folded in a gap between the pressing cylinder and the pressing inner container to form multiple wrinkles, at the moment, the pressing motor drives the driving disc to rotate by a certain angle, and then the inclined groove can drive all the vertical pressing rods to move inwards; all the vertical pressing rods, the expansion guide rods and the folding pressing rods can move inwards in the expansion sliding blocks until the folding pressing rods are attached to the press-fit inner container, the torsion motor drives the pipe shaft, the driving disc and the press-fit disc to twist back and forth by 30 degrees, and all wrinkles on the edge of the circular aluminum silicate fiber paper can be rolled back and forth by the folding pressing rods.

The utility model discloses a fracture testing machine which comprises a machine frame and a working table arranged on the machine frame, a support is arranged on the machine frame, an air cylinder is downwards arranged on the support, a weighing sensor is connected below a piston rod of the air cylinder, and a pressing block is arranged below the weighing sensor. The fracture testing machine provided by the utility model is simple in structure, low in manufacturing cost and easy to operate and maintain on the basis of ensuring that a fracture test can be effectively carried out on a workpiece.

The application discloses a novel straight-shear type concrete fracture performance test specimen and a test method. The test specimen is in the shape of an ectopic notch. During the test, the test specimen is placed between two loading plates, and the length direction of the concrete part is perpendicular to the two loading plates. The two loading plates are loaded towards each other. Relative to the concrete part, the compression deformation of the steel block is almost zero, thus causing the relative deformation difference between the concrete part and the steel block. The two loading plates are continuously loaded towards each other, and the concrete part is fractured along the predetermined position. The method forms the deformation difference in the stress redistribution process through the different material stiffness on both sides of the crack, realizes the opposite displacement within the range of the test specimen, and causes the dislocation cracking. Since the crack is caused by the deformation difference inside the concrete part, there is no bending tensile stress influence. The application is used for solving the index test of the II type fracture performance of brittle materials such as ordinary concrete and rockfill concrete, improving the existing test method, and eliminating the influence of the bending tensile stress in the II type fracture test.

The disclosure provides a crack analysis method, which can be applied to the technical fields of additive manufacturing and fracture mechanics. The crack analysis method comprises: determining a three-dimensional digital model of a biomimetic anti-fracture structure containing a designable hard fiber phase and a soft matrix phase feature; importing the three-dimensional digital model into the geometry preprocessing software of a material printing device for assembly to obtain a three-dimensional assembly model with the soft and hard phases adhered together; performing two-dimensional processing on the three-dimensional assembly digital model to obtain two-dimensional slice data containing the geometry of the soft and hard phases; importing the two-dimensional slice data into the material printing device for operation processing to obtain the optimal running track of the nozzle of the printing device and the type of material sprayed; layer by layer spraying and solidifying according to the optimal running track and the type of material sprayed to obtain a biomimetic anti-fracture structure sample containing a hard fiber and a soft matrix; performing a fracture test on the biomimetic anti-fracture structure sample, observing and analyzing the crack surface morphology and the fracture mode, and obtaining the observation results.

The invention relates to a device for testing hydrogen-induced delayed fracture of high-strength steel, and aims to solve the problems that in the prior art, stress on a sample is not uniform, and stress distribution does not conform to reality. The device is composed of a supporting seat, a sliding seat, a supporting guide rod, a hydraulic push rod, an extrusion sub-block, a pressing sheet, a fixing pad and the like. The hydraulic push rod drives the sliding seat to move up and down, the extrusion blocks move towards the center under the action of hydraulic oil, and the pressing pieces are matched with one another to apply uniform pre-bending force to the high-strength steel plate. The relative positions of the pressing pieces on the supporting base and the sliding base are adjustable, and different pre-bending faces can be formed. The fixing pad is made of polyurethane materials and has good elasticity and abrasion resistance, the mounting groove in the fixing pad is used for containing the high-strength steel plate, and the deformation condition of the steel plate can be conveniently observed through the through holes. By optimizing the structural design, the stress of the sample is uniform, the stress distribution is closer to the actual working condition, and the accuracy and reliability of the test result are remarkably improved.

The present invention relates to the technical field of coalbed methane exploration, and more specifically to a simulated specimen for hydraulic fracturing testing of a crushed soft coal seam and a preparation method thereof, comprising: an annular roof layer, the inner wall of which is provided with a simulated wellbore; an annular coal seam interface layer, located on the outer wall of the annular roof layer; and a coal seam, located on the outer wall of the annular coal seam interface layer, wherein the outer wall of the coal seam forms the four sides of the specimen. The simulated wellbore is arranged at the center of the annular roof layer. Through the annular structure of the annular roof layer and the annular coal seam interface layer, the simulated wellbore does not need to change its own axial position. Only by setting water outlets in different directions can the constructed fracture form a predetermined angle with the minimum stress direction. In addition, multiple fractures of different angles can be formed in one specimen. By comparing the morphology of fracture formation in one specimen, the relationship between the fracture formation angle and the minimum stress direction can be more accurately obtained.

The invention belongs to the technical field of geological engineering and hydraulic fracturing testing, and discloses a mine field level curve stress loading experiment device and method. The device comprises a curve stress applying system which comprises a bearing frame and a stress transfer reverse mold rubber body; the left side of the bearing frame is a flat surface, and the right side of the bearing frame is a preset curve surface; a left port of each stress loading layer is blocked and is provided with a liquid injection and drainage port, and a right port is irregular in shape, is matched with the curve surface of the right side of the bearing frame, is filled with an expansion material and is pre-provided with a temperature control heating device; the left side of the stress transfer reverse mold rubber body is a curved surface, the right side is a flat surface, and the left curved surface is matched with the right curved surface of the bearing frame and fixedly connected with the right ports of the stress loading layers in a wedging and sealing manner; the right side flat surface of the stress transfer reverse mold rubber body is attached to the stress surface of the rock sample. According to the invention, different fracturing sequences and pump injection programs can be simulated, gradient curve stress loading and pressurization are realized, and the experimental result is more practical.

The utility model discloses a fracture test device which comprises a plurality of fracture test units, and each fracture test unit comprises a support which is used for being connected with the bottom of a pole to fix the pole and is provided with an opening; the handle comprises a connecting rod and a plurality of connecting units, the connecting units are connected to the connecting rod, the connecting rod assembly penetrates through the opening to be connected with the connecting units, and the connecting units are arranged to be movable. And the connecting rods sequentially drive the plurality of connecting units through movement, and the plurality of connecting rods enable the plurality of insulating pull rods to respectively move towards directions far away from the plurality of poles so as to disconnect the arc extinguish chambers of the plurality of poles. According to the invention, the operation handle can be operated to simultaneously disconnect the arc extinguish chambers of a plurality of pole columns at one time, and the operation efficiency is greatly improved.

The present application relates to a zero-friction high earth-rock dam core wall gravel-mixed clay tensile-shear fracture test device, comprising a compaction fracture mold and a hollow test tank, wherein the compaction fracture mold is used for making a gravel-mixed clay soil sample, and comprises a test bearing part, a rectangular ring wall and a Z-shaped compaction plate, and a rectangular recess is formed at the top center of the hollow test tank. Through the design of the floating cavity, the compaction fracture mold test part is separated from the working platform by skillfully using the air bag group and the buoyancy principle, thereby fundamentally solving the friction between the mold and the platform, greatly enriching the test means of the fracture characteristics of the gravel-mixed clay, the design of multiple air bags in the air bag group facilitates the leveling of the test part of the compaction fracture mold, the operation is simple and convenient, the detection accuracy can be significantly improved, the tensile fracture and shear fracture characteristics are measured at the same time, and the accurate tensile fracture characteristics and shear fracture characteristics of the high earth-rock dam gravel-mixed clay soil sample are analyzed.

The utility model provides a fracture test tool for a collateral dredging instrument, a transmission mechanism, a measuring mechanism and a fixing mechanism are arranged on a test tool body, and a product to be tested is fixed by using the fixing mechanism; the transmission mechanism comprises a transmission seat and a testing head, the testing head abuts against a preset position of the to-be-tested product, and the transmission seat drives the testing head to apply force to the to-be-tested product; the measuring mechanism is arranged between the transmission seat and the testing head and is used for detecting the magnitude of applied force, the to-be-tested product comprises a base and a head part, a holding part is arranged between the base and the head part, a connecting assembly is arranged in the holding part, and the head part is installed on the base through the connecting assembly. The beneficial effects of the utility model are that: firstly, the appropriate profiling cushion block is selected to fix the product to be tested by using the fixing mechanism, and then the test head is used to apply force to the specific part of the product to be tested from the side until the applied force when the specific part is fractured is obtained along with the increase of the applied force; and the performance parameters of the batch of products can be conveniently obtained.

The invention relates to a method for positioning bulk materials (10, 14, 15) of a certain type in a fracture chamber (1) of a testing device (2) comprising the following successive steps: - a bulk material (10, 14, 15) of this particular type is introduced into the fracture chamber (1) of the testing device (2), wherein the fracture chamber (1) has a fracture test area (25); - at least one camera (26) checks, using a stored reference image, whether the bulk material (10, 14, 15) is arranged in the fracture test area (25) of the fracture chamber (1); - if the bulk material (10, 14, 15) is not in the fracture test area (25), the bulk material (10, 14, 15) is moved in the fracture chamber (1) by a movement mechanism (7, 4) until the bulk material (10, 14, 15) is arranged in the fracture test area (25).

This invention discloses a method for testing Type I fracture under cyclic thermodynamic loading. It couples a three-point bending test with stress-temperature cycling, extending the three-point bending test to thermodynamic experimental conditions. By measuring the peak load S in the three-point bending test and the elastic modulus E in the final stress-temperature cycle, the fracture energy Gc of the Type I fracture of the specimen under cyclic thermodynamic loading can be effectively calculated. This helps to accurately reflect the bearing capacity and fracture propagation mode of the fractured surrounding rock in compressed gas storage caverns under cyclic thermodynamic loading. The method couples stress and temperature cycles and measures the change in the elastic modulus of the specimen under cyclic stress and temperature. This method has the advantages of simple steps, quick and convenient testing, and strong practicality. It is easy to operate, has a wide range of applications, and can be combined according to different actual working conditions to meet the needs of Type I fracture testing under different specimen materials, loading temperatures, and loading conditions.

The present invention belongs to the technical field of biomaterial mechanical property testing instruments, and relates to an expansion device and method for viscoelastic damage and fracture testing of soft materials, the device comprising: a control module, a pressure module, and a fixture module; wherein the control module is used to output the driving signal required for the viscoelastic damage and fracture testing to the pressure module; the pressure module is used to compress the gas and / or liquid in the cylinder at a variable rate by driving the lead screw forward and backward through a motor under the action of the driving signal, and apply an equibiaxial, variable rate expansion load to the soft material to be tested in the fixture module to achieve viscoelastic damage and fracture testing; the fixture module includes a front seat and a rear seat, which clamp the soft material to be tested through a gasket. The device and method of the present invention can meet the requirements of viscoelastic damage and fracture testing by controlling the pressure change on the basis of meeting the equibiaxial mechanical loading conditions of the soft material.

The invention relates to the technical field of rock mass drill hole deformation testing, and particularly provides a humidity-adjustable rock mass drill hole deformation and micro-fracture testing device and a humidity-adjustable rock mass drill hole deformation and micro-fracture testing method. The environment box defines a containing cavity and is used for containing a rock mass model, and the inner contour of the containing cavity and the outer contour of the rock mass model are complementary in shape; the two groups of loading assemblies respectively penetrate through the environment box, are connected to two pairs of opposite transverse side surfaces of the rock mass model and apply loads to the rock mass model, and the two groups of loading assemblies are in sealing fit with the environment box; the humidity loading assembly comprises a liquid conveying pipe and a plurality of isolation components, the rock mass model is provided with a drill hole, the environment box is provided with a through hole, the liquid conveying pipe penetrates through the through hole and is inserted into the drill hole, and all the isolation components extend into the drill hole so as to carry out partition control on the drill hole loading humidity. Through the configuration, the mechanical response of the rock mass model in a complex stress environment and the analysis of the influence of the humidity-rigidity-strain coupling effect on the rock mass model are realized.

This invention relates to an auxiliary device for a dry hot rock cold damage fracture test. The technical solution adopted by this invention is: an auxiliary device for a dry hot rock cold damage fracture test, characterized in that: it has a base plate for placement; on the base plate, via a transport mechanism, is an injection mechanism for filling the edge of the gap between two samples with epoxy resin and sealing the gap; on both sides of the base plate where the samples are placed, there are water pipe installation mechanisms for embedding water pipes into the epoxy resin between the two samples. Thus, the transport mechanism drives the injection mechanism to move uniformly around the samples on the base plate, facilitating the uniform injection of epoxy resin into the edge of the gap between the two samples; the water pipe installation mechanisms facilitate the installation of two water pipes into the epoxy resin on both sides of the samples, one water pipe serving as an inlet pipe and the other as an outlet pipe, realizing water circulation between the samples and the outside environment.

A needle tester, which relates to the technical field of needle testing, includes a bracket, and further includes: a placement plate for placing a specimen; a pressure sensor, one side of which is fixedly connected to the placement plate, and the other side of which is arranged on the bracket through a first transmission member; a needle plate for placing needles, which is arranged on a fixed beam, and the fixed beam is connected to a second transmission member; and an electric control device arranged on the bracket for controlling the operation of the tester; wherein, when the placement plate and the needle plate reciprocate relative to each other, the needles reciprocally insert into and withdraw from the specimen; or, when the placement plate and the needle plate move relative to each other, the needles impact the specimen. The beneficial effects of the present invention are as follows: It can accurately test the needles, making the acting force for testing the needles always stable in position and the force simulation more accurate; this tester has multiple functions and can conduct resilience tests, wear tests, impact resistance tests, temperature rise tests, bending fatigue tests, anti-bending break angle tests, and fracture tests.

The invention discloses an injection molding part testing device for injection molding quality control, which belongs to the field of injection molding part testing and comprises a base, an air bag cover plate, a high-pressure air storage bottle, a testing push cylinder, a sealing barrel, an airflow impact assembly, a fracture testing assembly, a testing table, a positioning groove, a locking mechanism, a fragment scattering testing assembly and a projection lamp. By arranging the airflow impact assembly, high-pressure gas gathers and rotates in the vortex ring generation cavity and is eccentrically sprayed out through the energy-gathered jet flow cavity, speed difference is formed to induce multi-scale vortexes, a disordered turbulent flow field is generated to simulate explosion impact, by arranging the fragment interception tower, low-kinetic-energy fragments are captured by the adhesive layer, high-kinetic-energy fragments are embedded into the interception lining to be fixed, and the explosion impact is simulated. The number, the size, the shape, the distribution density and the direction of the fragments are tested, by arranging the fracture testing assembly, when the air bag cover plate is not fractured, high-pressure nitrogen pushes the sealing plunger to slide to expose the pressure relief hole to relieve pressure, and the stabilizer bar impacts and triggers the pressure sensor.

The utility model relates to the technical field of impact tests, in particular to a pendulum bob type impact testing machine for plastic detection. The utility model aims to solve the problems that a plastic part is broken and flies out during a test piece fracture test and is easy to rebound, the protection performance of a protection net is reduced, and the safety performance is low. When a fractured test piece flies out and impacts the protective net installed on the baffle, the impact force of the fractured test piece can be effectively relieved, the situation that the fractured test piece rebounds is avoided, the operation safety is improved, the fractured test piece falls into the groove in the baffle when subjected to resistance of the protective net, and the fractured test piece is collected and treated in a unified mode; and the structure is simple, the protection effect is good, the operation safety is improved, the clamping and fixing assembly is matched, the plastic part is rapidly clamped and fixed through the clamping block, the structure is simple, operation is convenient, the good clamping effect can be provided, and the working efficiency is improved. And the test accuracy of the plastic part is improved.

The present application provides a kind of rail fracture test method, comprising the following steps: step one: through the vibration sensor of vehicle running part axle box end, collect the vibration displacement of vehicle running part to steel rail;Step two: vibration sensor converts the collected mechanical vibration displacement into electrical signal, and is transmitted to the signal acquisition instrument of test equipment;Step three: signal processing unit is calculated and deduced to the deflection deformation of steel rail by formula through mechanics principle;Step four: the bending stiffness of the section steel rail is calculated by formula;Step five: test equipment is further calculated according to the collected deflection displacement data and bending stiffness data of steel rail The vertical vibration displacement and change rate of steel rail are calculated by formula;Step six: test equipment will automatically complete the detection, analysis and judgment of steel rail according to the obtained data;Solve the problem that user needs to manually operate and identify when testing by traditional flaw detection vehicle, without special arrangement of skylight time for testing, improve the efficiency of testing.

This invention relates to the field of hydraulic fracturing testing technology, and particularly to a fracture monitoring method, a brine hydraulic fracturing experimental apparatus, system, electronic equipment, and medium. The method includes: adjusting the concentration of the injected brine using a brine concentration control module based on a preset concentration curve, the concentration curve dynamically changing with experimental time or real-time multiphysics feedback data; during the hydraulic fracturing process of the injected brine, acquiring multiphysics data of the target fracture using a multiphysics monitoring module; and calculating the blockage state and salting-out degree of the target fracture using a multiphysics coupling analysis algorithm based on the multiphysics data. This approach solves the technical problem of existing technologies being unable to monitor the multiphysics coupling process under high temperature and high salinity conditions, improving the depth of research and the fidelity of experimental simulations regarding the fracture salting-out blockage mechanism during brine discharge from salt cavern-type compressed air energy storage.

The fillet weld fracture testing device comprises a frame body and a hydraulic jack, the frame body is composed of a bottom plate, two side stand columns, a pressing block and a pressing plate, the stand columns are symmetrically welded to the bottom plate, the two sides of the pressing block are welded to the tops of the inner sides of the stand columns respectively, the hydraulic jack is placed on the bottom plate, the pressing plate is placed on the hydraulic jack, and a limiting ring is fixed to the middle of the bottom face of a top plate. The inner diameter of the limiting ring is matched with a disc on the top face of a telescopic rod of the hydraulic jack, the distance between the front side plate and the rear side plate is smaller than the diameter of the top face of a machine body of the hydraulic jack, and when the telescopic rod retracts, the side plates fall on the top face of a main body of the hydraulic jack to form supporting. A welding part is placed on the pressing plate and is lifted upwards through the hydraulic jack, a fracture test is carried out under extrusion of the pressing block and the pressing plate, the pressing plate is provided with the side plate and the limiting ring, the pressing plate and the hydraulic jack can form a firm fixing relation, displacement is prevented, and the safety and efficiency of the test are improved.