CN116087004A - Angle-adjustable fastener fatigue test device - Google Patents

Abstract

The invention discloses an angle-adjustable fastener fatigue test device, which comprises: the fixture comprises a fixture platform for installing a test piece, wherein an arc-shaped beam which is supported and fixed through a reaction frame is arranged on the periphery of the fixture platform, a pair of loading units which extend along the radial direction of the arc-shaped beam and can be positioned on the arc-shaped beam for circumferential angle adjustment are arranged on the arc-shaped beam, and the ends of the pair of loading units, which face the test piece, are respectively arranged to act on two sides of the test piece. This fastener fatigue test device can set up different atress contained angles through two loading units of cooperation according to the test demand, cooperates the frock of different models, can carry out complicated fatigue performance test, provides the design foundation for fastener system research.

Description

Angle-adjustable fastener fatigue test device

Technical Field

The invention relates to the technical field of railway engineering, in particular to an angle-adjustable fastener fatigue test device.

Background

The rail fastener system, which is a key component of the track system, should have sufficient fastening force and certain elasticity, and its main function is to connect the rail with the under-rail base part, which plays an important role in maintaining the stability of the track structure.

In recent years, with the gradual expansion of the research on the fatigue performance of the spring strip of the high-speed railway fastener system, the research on the fatigue experiment of the fastener system is also gradually in depth, and a mathematical model is built and analyzed at the key stage of the fatigue process identification, so that the method has great significance for judging the long-term use performance of the fastener.

The core of the fatigue test device for the fastener system is mainly a stress application frame, and a sample is loaded through the stress application frame during fatigue test, so that the fatigue test of the fastener is researched.

At present, the test device for simultaneously loading one steel rail at multiple angles to test the assembly fatigue performance of the fastener is still in a technical blank state.

Disclosure of Invention

The invention aims to provide an angle-adjustable fastener fatigue test device, which can set different stress included angles according to test requirements through two loading units, can perform complex fatigue performance tests and provides design basis for fastener system research.

In order to achieve the above object, the present invention provides an angle-adjustable fastener fatigue test apparatus, comprising: the fixture comprises a fixture platform for installing a test piece, wherein an arc-shaped beam which is supported and fixed through a reaction frame is arranged on the periphery of the fixture platform, a pair of loading units which extend along the radial direction of the arc-shaped beam and can be positioned on the arc-shaped beam for circumferential angle adjustment are arranged on the arc-shaped beam, and the ends of the loading units, which face the test piece, are respectively arranged to act on two sides of the test piece.

Preferably, the loading unit includes: and the MTS actuator is perpendicular to the tangential direction of the arc beam and is in sliding clamping connection with the arc beam, and an MTS sensor and a loading tool head are sequentially arranged at the end part of the MTS actuator, which faces the test piece.

Preferably, an arc roller way is arranged on the upper surface of the arc beam, and travelling wheels corresponding to the arc roller way are arranged on a structural member, which is used for clamping the arc beam, on the MTS actuator; the fixed chain is arranged at the outer side of the arc roller way on the arc beam, a pair of motors capable of synchronously starting and stopping are arranged on the structural member, and a chain wheel capable of being positioned on the fixed chain and matched with rolling is arranged on the shaft body of the motor.

Preferably, each MTS actuator is symmetrically provided with two structural members along two sides parallel to the axial direction of the arc-shaped beam, and the arc-shaped beam is correspondingly provided with two structural members.

Preferably, a plurality of hoisting rings are arranged on the tooling platform.

Preferably, an iron floor is arranged below the tooling platform, and the tooling platform is arranged on the iron floor and can adjust transverse displacement along an axial direction parallel to the arc beam.

Preferably, the horizontal movement driving mechanism capable of driving the tooling platform to move is arranged on the iron floor, a horizontal sliding rail is further arranged on the iron floor, and a guide rail block matched with the horizontal sliding rail is arranged on the bottom surface of the tooling platform.

Preferably, horizontal locking mechanisms for clamping or loosening the tooling platform are arranged on the two sides of the tooling platform on the iron floor.

Preferably, a lifting mechanism is arranged below the iron floor; the iron floor is characterized in that the two sides of the iron floor are provided with reverse sliding modules, the side surface of the reaction frame facing the iron floor is a vertical surface, and the vertical surface is provided with lifting sliding rails corresponding to the reverse sliding modules.

Preferably, the lifting mechanism is supported and arranged on the T-shaped bottom beam, the counterforce frame is arranged at a position extending transversely to the T-shaped bottom beam, and the lifting mechanism is arranged at a position extending longitudinally to the T-shaped bottom beam.

According to the technical scheme, the fatigue test device for the fastener can set different stress included angles according to test requirements through the two loading units, can perform complex fatigue performance tests, and provides design basis for fastener system research.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate the invention and together with the description serve to explain, without limitation, the invention. In the drawings:

FIG. 1 is a front view of a preferred embodiment of a fastener fatigue testing device;

FIG. 2 is an overall view of a preferred embodiment of a fastener fatigue test apparatus.

Description of the reference numerals

A 1-T-shaped bottom beam; 2-steering gear; 3-a servo motor; 4-screw elevator; 5-lifting sliding rails; 6-a horizontal locking mechanism; 7-a tooling platform; 8-lifting rings; 9-travelling wheels; 10-double servo motors; 11-an arc roller way; a 12-MTS actuator; 13-MTS sensor; 14-loading a tool head; 15-test piece; 16-arc beam; 17-a horizontal movement driving mechanism; 18-horizontal slide rails; 19-iron floor; 20-a reaction frame; 21-a structural member; 22-fixing the chain; 23-sprocket; 24-sleeper.

Detailed Description

The following describes specific embodiments of the present invention in detail with reference to the drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the invention, are not intended to limit the invention.

In the present invention, unless otherwise indicated, terms such as "upper, lower, left, right, front, rear, and inner and outer" and the like are used merely to denote the orientation of the term in a conventional use state or are commonly understood by those skilled in the art, and should not be construed as limiting the term.

Referring to the angle-adjustable fastener fatigue test apparatus shown in fig. 1-2, the fastener fatigue test apparatus comprises: the fixture platform 7 for installing the test piece 15 is arranged on the periphery of the fixture platform 7, an arc-shaped beam 16 which is supported and fixed through a reaction frame 20 is arranged on the periphery of the fixture platform 7, a pair of loading units which extend along the radial direction of the arc-shaped beam 16 and can be positioned on the arc-shaped beam 16 for circumferentially adjusting angles are arranged on the arc-shaped beam 16, and the ends of the loading units, which face the test piece 15, are respectively arranged to act on two sides of the test piece 15.

At present, when the assembly fatigue test is performed on the sleeper 24, in order to simulate different stress states of the fasteners under different line conditions, the angle of the loading frame needs to be adjusted according to actual working conditions. Considering that the existing loading frame is stressed greatly, the position of the fixed shaft is designed to be in an unadjustable mode, so that the reliability of the loading frame is ensured. Because the track gauge value after the fastener assembly is fixed, therefore the loading frame can only carry out the fastener fatigue test to an angle, when the assembly fatigue test is needed to be carried out to different types of fasteners, a laboratory usually adopts a mode of changing different types of loading frames, and because the process of changing the loading frames is more complicated, the process of adjusting is more complex, not only occupies the field of the laboratory, but also increases the cost, and needs to carry out necessary improvement. Therefore, the research and development of the fatigue test device for the angle-adjustable fastener has great significance for the research of the fastener, namely the track structure system.

Through implementation of the technical scheme, the fastener fatigue test device can set different stress included angles according to test requirements through the two loading units, and can be matched with loading tools of different models to perform complex fatigue performance tests, so that design basis is provided for fastener system research.

In this embodiment, in order to further provide a loading unit, the loading unit includes: and the MTS actuator 12 is perpendicular to the tangential direction of the arc beam 16 and is in sliding clamping connection with the arc beam 16, and the end part of the MTS actuator 12 facing the test piece 15 is sequentially provided with an MTS sensor 13 and a loading tool head 14. In the invention, the arc beam 16 is arc-shaped, so that the bearing capacity can be higher, and meanwhile, as the arc beam 16 adopts the arc shape, the two MTS actuators 12 can always face the circle center position of the arc shape, namely, can make arc-shaped movement around the steel rail to adjust the angle. The loading tool head 14 is used for directly loading the test piece 15, namely the steel rail, and the specific loading position is shown in fig. 1, and in addition, test data can be acquired through the MTS sensor 13 for later analysis.

For example, in one embodiment, two actuators with 150kN and loading frequency in the low frequency range of 3Hz-5Hz are used for collaborative test, the two actuators output dynamic force values to the tested piece according to the same or different waveforms, the two actuators can be changed to be positioned at different positions in the loading test process, and the angle of the applied force is changed, so that more test data are obtained.

In this embodiment, an arc roller way 11 is disposed on the upper surface of the arc beam 16, and a travelling wheel 9 corresponding to the arc roller way 11 is disposed on a structural member 21 on the MTS actuator 12 for clamping the arc beam 16; the arc-shaped beam 16 is provided with a fixed chain 22 at the outer side of the arc-shaped roller way 11, the structural member 21 is provided with a pair of motors capable of synchronously starting and stopping, and the shaft body of each motor is provided with a chain wheel 23 capable of being positioned on the fixed chain 22 to match and roll. The arc beam 16 adopts a ring-shaped bearing frame, on which a motor is arranged to independently drive a chain wheel 23, the chain wheel 23 is positioned on a fixed chain 22 to roll so as to adjust the position, a slidable loading frame fixer is the structural member 21, and the function of installing the travelling wheel 9 on the loading frame fixer is to match the upper surface of the arc roller way 11 to slide, so that the auxiliary guiding function is realized, and generally, one travelling wheel 9 is respectively arranged at two ends of the travelling wheel 9 in the advancing direction, so that the stability of rolling operation can be improved.

In this embodiment, each of the MTS actuators 12 is symmetrically provided with two structural members 21 along both sides in the axial direction parallel to the arc beams 16, and the arc beams 16 are provided with two structural members 21. Namely, two parallel arc beams 16 are arranged along the front-rear direction, a gap for allowing the MTS actuator 12 to pass through is formed between the two arc beams 16, the front side and the rear side of the MTS actuator 12 are respectively arranged on the two structural members 21, the two adjacent structural members 21 are identical in structure and are respectively provided with the travelling wheels 9, the two arc beams 16 are identical in structure and are respectively provided with an arc roller way 11 and a fixed chain 22, motors are respectively arranged on the outer sides of the two arc beams 16, and the two motors respectively drive corresponding chain wheels 23 to be located on the respective chain wheels 23 for synchronous travelling.

In addition, for increasing holistic operational stability, be provided with connection structure between two structure 21, be that the upper end of two structure 21 passes through connection structure fixed connection for two structure 21 form holistic structure, in addition, can adopt the bolt to dismantle between two structure 21 and the connection structure and be connected, make things convenient for the dismantlement maintenance in the future. The MTS actuator 12 is mounted to the connection structure, although the MTS actuator 12 base could be used directly as the connection structure.

The motor at the outer side of the arc beam 16 adopts a double-servo motor 10, and the double-servo motor 10 and a chain wheel 23 are adopted to drive the integral loading part to move in an arc shape during movement; the universal ball can be used for being attached to the side face of the arc-shaped beam 16 for limiting during movement, so that the parallel movement is ensured, deflection and clamping stagnation are prevented, and the actuator is ensured to freely walk on the arc-shaped roller way 11; the minimum loading angle of two actuators is 45 degrees, and both actuators can perform horizontal loading. Real-time control can be carried out through a touch screen or a display screen, and convenience in the experimental process is guaranteed.

In addition, the device can also comprise an arc locking mechanism arranged on the structural member 21, and the arc locking mechanism drives the loading part to integrally move when being loaded, so that the bearing block on the loading part is tightly attached to the inner ring of the arc beam 16 to be locked, and the driving mechanism of the arc locking mechanism can be an oil cylinder.

Of course, the bottoms of the two arc beams 16 can also be welded into an integral structure through steel plates, and the steel plates and the reaction frame 20 can be detachably mounted through a plurality of bolts, so that the integral structure is more stable and easy to detach.

In this embodiment, in order to facilitate lifting and transferring, installation and debugging and later maintenance are facilitated, a plurality of lifting rings 8 are arranged on the tooling platform 7. The number and mounting position of the lifting loops 8 can be chosen as desired, for example: 4 lifting rings 8 are arranged and are respectively positioned near 4 corners of the tooling platform 7.

In this embodiment, a ferrous floor 19 is provided below the tooling platform 7, and the tooling platform 7 is provided on the ferrous floor 19 and is capable of adjusting lateral displacement in an axial direction parallel to the arcuate beam 16. By arranging the iron floor 19, the tooling platform 7 can horizontally move so as to load and unload the test piece 15. The two ends of the iron floor 19 can be provided with the stop pieces, so that the tool platform 7 is prevented from slipping off, the stop pieces can be replaced by limit switches, and when the end part of the tool platform 7 is close to the limit switches, the stop pieces are fed back to the system and guide the tool platform 7 to stop running continuously.

In this embodiment, a plurality of parallel T-shaped grooves may be provided on the tooling platform 7 for mounting the sleeper 24 and the test tooling on the tooling platform 7, and fastening may be performed by T-shaped blocks and bolts. The rail is then mounted on the sleeper 24 by spring strips.

In this embodiment, the horizontal movement driving mechanism 17 capable of driving the tooling platform 7 to move is disposed on the iron floor 19, a horizontal slide rail 18 and a rack are further disposed on the iron floor 19, and a guide rail block and a gear matched with the horizontal slide rail 18 are disposed on the bottom surface of the tooling platform 7. The moving accuracy of the tooling platform 7 can be further improved through the horizontal moving driving mechanism. The tool platform 7 can longitudinally move out of the arc loading frame along with the test platform under the drive of a horizontal movement driving mechanism 17, such as a stepping motor and meshing of a gear and a rack, so that the test sample can be conveniently installed and replaced.

The horizontal movement driving mechanism consists of a stepping motor, a speed reducer, a gear, a rack, a guide rail, a limiting block and the like. And a high-precision guide rail is selected, so that smooth walking and repeated precision are ensured. The linear guide rail and the lower platform are used for positioning, the total number of the guide rail blocks is 8, and the bearing of the independent guide rail blocks is not less than 150kN, so that the bearing requirement is met. The horizontal movement is realized through a stepping motor, a speed reducer, a driving gear and a rack. The horizontal movement function of the tooling platform 7 can be controlled in real time through a touch screen or a display screen, so that convenience in the experimental process is ensured.

In this embodiment, horizontal locking mechanisms 6 for clamping or unclamping the tooling platform 7 are arranged on the iron floor 19 at two sides of the tooling platform 7. In order to prevent the guide rail from bearing a large load when the oil cylinder in the MTS sensor 13 is subjected to angle loading, a horizontal locking mechanism 6 is designed. When the tooling platform 7 moves horizontally to the test position, the transversely extending nuts on the horizontal locking mechanism 6 are screwed down, so that the tooling platform 7 and the side supports are tightly supported to bear horizontal load.

The tooling platform 7 and the iron floor 19 are integrally cast by gray cast iron, and are machined after casting, so that the surface precision and strength requirements are ensured. The tooling platform 7 is connected with the reaction frame 20 through the lifting slide rail 5, and resists the influence of lateral force on the lifter in the test process along with the lifting of the platform.

In this embodiment, a lifting mechanism is provided below the iron floor 19; the two sides of the iron floor 19 are provided with reverse sliding modules, the side surface of the reaction frame 20 facing the iron floor 19 is a vertical surface, and the vertical surface is provided with lifting sliding rails 5 corresponding to the reverse sliding modules.

For example, in one embodiment, the lifting mechanism is composed of a servo motor 3, a worm gear reducer, a steering gear 2 and a screw lifter 4, and the lifting stroke is about 400 mm. The six spiral lifters 4 work simultaneously, and a rigid coupling is adopted to ensure that the six lifters are arranged on the same horizontal plane and can synchronously move; unified adjustment is performed before installation, so that the same initial angle state is ensured; the upper mounting flange can be adjusted in height; the lateral force resistance of the lifting platform is compensated by a horizontal locking mechanism 6. By the mode, the defect that the linkage motions of the plurality of lifters are asynchronous can be avoided to the greatest extent, so that the accuracy of test results is guaranteed, and the heights of different sleepers 24 can be adjusted under the condition that the stability of a system is guaranteed. The servo motor 3 is responsible for driving the whole system to drive the mobile platform system to carry out height adjustment, closed-loop control is carried out through the servo motor 3 driver and the PLC simultaneously, and real-time control is carried out in cooperation with the touch screen or the display screen, so that the positioning of the height position of the tooling platform 7 is realized, and the convenience of the experimental process is ensured.

The spiral lifter 4 drives the platform to lift to a designated position, the locking oil cylinder drives the locking support to clamp the lifting screw rod to prevent the movement, the stability and the reliability of the lifting platform are improved, and then a loading fatigue test is carried out.

In this embodiment, the lifting mechanism is supported by the T-shaped bottom beam 1, the reaction frame 20 is disposed at a position extending in the lateral direction from the T-shaped bottom beam 1, and the lifting mechanism is disposed at a position extending in the longitudinal direction from the T-shaped bottom beam 1. By the arrangement, the occupied area of the whole equipment can be saved to the greatest extent. The arc beam 16, the T-shaped bottom beam 1 and the reaction frame 20 form an annular bearing frame together, and the main body material is processed by adopting Q345B post-welding aging treatment.

The annular bearing frame can bear part of bearing, and the maximum vertical bearing is required to be ensured to be not lower than 300kN; the maximum horizontal bearing is not lower than + -200 kN. The arc beams 16 on the two sides are formed by one-step processing, so that the consistency of the arc beams is ensured, the two MTS actuators 12 can perform circular motion on the annular roller way by matching with the travelling wheels 9, and the intersection point of extension lines of the loading heads of the two actuators is ensured to be positioned on the circle center of the annular bearing frame. The reaction frame 20 is required to be kept vertical during processing. Under the condition of ensuring the integral strength, the requirement of mounting precision is ensured. The joint is provided with a positioning spigot and a positioning pin, so that the integral assembly precision, strength and shearing resistance are ensured.

With the gradual expansion of research on fatigue performance of spring strips of a high-speed railway fastener system in recent years, a fatigue experiment on the fastener system needs to be developed, and a key stage parameter model for fatigue process identification is provided. Therefore, the research and development of the angle-adjustable fatigue testing machine has great significance for the research of the fasteners and the track structure system, and fills the technical reserve blank in the field of the bidirectional loading of the angle-adjustable fasteners at present.

In addition, the invention can be provided with an integrated control system, so that fatigue tests can be more accurately and efficiently carried out on fasteners of various types, for example, the needed position information of the fasteners of corresponding types and the steel rail can be input into the system, and the steel rail of corresponding types can be directly selected for automatic adjustment of the machine position and automatic fatigue test when the test is carried out next time.

Of course, in the present invention, an angle scale may be provided on the outer side of the inner ring of the arc beam 16, and a scale pointer may be provided on the side of the MTS actuator 12, which scale pointer is used in conjunction with the angle scale, so as to quickly understand the loading angle.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the scope of the technical concept of the present invention, and all the simple modifications belong to the protection scope of the present invention.

In addition, the specific features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various possible combinations are not described further.

Moreover, any combination of the various embodiments of the invention can be made without departing from the spirit of the invention, which should also be considered as disclosed herein.

Claims (10)

1. An adjustable angle's fastener fatigue test device, its characterized in that, fastener fatigue test device includes: a frock platform (7) for installing test piece (15), the periphery of frock platform (7) is provided with arc roof beam (16) that support fixedly through reaction frame (20), be provided with a pair of along its radial direction extension and can be located on arc roof beam (16) circumference angle regulation's loading unit, a pair of loading unit each face the tip setting of test piece (15) and are acted on both sides of test piece (15) respectively.

2. The angle-adjustable fastener fatigue test apparatus of claim 1, wherein the loading unit comprises: and the MTS actuator (12) is perpendicular to the tangential direction of the arc-shaped beam (16) and is in sliding clamping connection with the arc-shaped beam (16), and an MTS sensor (13) and a loading tool head (14) are sequentially arranged at the end part of the MTS actuator (12) facing the test piece (15).

3. The fatigue test device for the angle-adjustable fastener according to claim 2, wherein an arc roller way (11) is arranged on the upper surface of the arc-shaped beam (16), and travelling wheels (9) corresponding to the arc roller way (11) are arranged on a structural member (21) on the MTS actuator (12) for clamping the arc-shaped beam (16);

the novel roller table is characterized in that a fixed chain (22) is arranged on the arc-shaped beam (16) and located at the outer side of the arc-shaped roller table (11), a pair of motors capable of being synchronously started and stopped are arranged on the structural member (21), and a sprocket (23) capable of being located on the fixed chain (22) and matched with the rollers is arranged on the shaft body of the motor.

4. An adjustable angle fastener fatigue testing device according to claim 3, wherein each MTS actuator (12) is symmetrically provided with two structural members (21) along two sides parallel to the axial direction of the arc-shaped beam (16), and the arc-shaped beam (16) is correspondingly provided with two structural members (21).

5. The fatigue test device for the angle-adjustable fastener according to claim 1, wherein a plurality of hoisting rings (8) are arranged on the tool platform (7).

6. The angle-adjustable fastener fatigue testing device according to any one of claims 1-5, wherein an iron floor (19) is provided below the tooling platform (7), the tooling platform (7) being provided on the iron floor (19) and being capable of adjusting lateral displacement in an axial direction parallel to the arc beam (16).

7. The fatigue test device for the angle-adjustable fastener according to claim 6, wherein a horizontal movement driving mechanism (17) capable of driving the tooling platform (7) to move is arranged on the iron floor (19), a horizontal sliding rail (18) is further arranged on the iron floor (19), and a guide rail block matched with the horizontal sliding rail (18) is arranged on the bottom surface of the tooling platform (7).

8. The fatigue test device for the angle-adjustable fastener according to claim 6, wherein horizontal locking mechanisms (6) for clamping or unclamping the tooling platform (7) are arranged on two sides of the tooling platform (7) on the iron floor (19).

9. The fatigue test device for the angle-adjustable fastener according to claim 6, wherein a lifting mechanism is arranged below the iron floor (19);

the two sides of the iron floor (19) are provided with reverse sliding modules, the side surface of the reaction frame (20) facing the iron floor (19) is a vertical surface, and the vertical surface is provided with a lifting sliding rail (5) corresponding to the reverse sliding modules.

10. The fatigue test device for the angle-adjustable fastener according to claim 9, wherein the lifting mechanism is supported and arranged on the T-shaped bottom beam (1), the reaction frame (20) is symmetrically arranged at a position extending transversely to the T-shaped bottom beam (1), and the lifting mechanism is arranged at a position extending longitudinally to the T-shaped bottom beam (1).

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