Lightweight wheel-rail force calibration method and device

Abstract

The application discloses a light-weight wheel-rail force calibration method and device, wherein three easily detachable clamps are designed in the device part to hold the side ends and the middle part of the steel rail. The top of the left and right clamps is connected with the two ends of a cable, the middle part of the cable is arranged in the slide way on the cylindrical structure of the force measuring mechanism arranged on the middle clamp, and the middle part of the cable is in contact with the output end of the jack in the force measuring mechanism. When the wheel-rail force calibration is carried out, the jack is matched with the cable to apply pressure to the vertical and horizontal directions of the steel rail test section, and the force sensor and the steel rail strain signal are recorded during the process, so that the vertical and horizontal force calibration of the steel rail to be tested is completed. The rail horizontal and vertical force data when the train passes through the steel rail to be tested can be obtained through the calibration structure. The application can effectively improve the wheel-rail force test efficiency and accuracy, and the parts are simple and light in weight, and are convenient to install and carry.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of railway testing, and relates to a light-weight wheel-rail force calibration device and a testing method. BACKGROUND

[0002] Rail transportation is an important infrastructure, but there is a problem of wheel-rail force in rail transportation. Excessive or uneven wheel-rail force can cause unstable operation of the train, and even cause safety accidents. In order to ensure the safety and stability of rail transportation, wheel-rail force testing is a very important work.

[0003] Through wheel-rail force testing, important indicators such as derailment coefficient and wheel load reduction rate when the train passes can be analyzed, so that corresponding rail grinding strategies can be developed according to the relevant indicators, and the effect of rail grinding can also be measured to judge whether the train tends to be stable when passing the ground rail after grinding.

[0004] As one of the key steps of wheel-rail force testing, wheel-rail force calibration is a step that occupies a long track time and has a large workload. The traditional calibration device has a complex structure, a large volume, and a complicated installation. In addition, the track needs to be occupied throughout the calibration process, and vehicles are not allowed to pass through. Therefore, the wheel-rail force testing efficiency is greatly reduced due to the short sky window time.

[0005] Therefore, a light-weight, simple-to-disassemble, and easy-to-convert horizontal and vertical testing device and method are needed to improve the testing efficiency and accuracy. SUMMARY

[0006] In view of the above deficiencies in the prior art, in order to simply, quickly and accurately calibrate the wheel-rail force and provide strong support for improving the efficiency and accuracy of wheel-rail force testing, the present application provides a light-weight wheel-rail force calibration device and a testing method, which can effectively improve the efficiency and accuracy of wheel-rail force testing.

[0007] The light-weight wheel-rail force calibration device of the present application comprises a clamp, a force measuring mechanism and a jack cable.

[0008] The clamp comprises end clamps for clamping both ends of the rail test section and a middle clamp for clamping the middle part of the rail test section; the top surface and the side surface of the middle clamp are force measuring mechanism installation positions for installing the force measuring mechanism to apply vertical force and horizontal force to the clamped rail.

[0009] The side force mechanism comprises a force sensor, a jack placement cylinder and a jack; the force sensor is installed on the middle clamp; the jack placement cylinder is coaxially fixed with the force sensor; the jack is located inside the jack placement cylinder; the jack placement cylinder has an opening on the opposite side wall for setting the jack cable.

[0010] The thousand jack cable is arranged along the length direction of the steel rail, and the top end of the thousand jack placing cylinder is arranged in the opening on the opposite sides of the thousand jack placing cylinder; the two end ring-shaped connecting ends of the thousand jack cable pass through the through holes on the rectangular blocks designed on the top of the two end clamps, and are connected with the rectangular blocks; and the middle part of the thousand jack cable is in contact with the piston at the end of the output end of the thousand jack. Thus, by controlling the output force of the thousand jack, the thousand jack cable is gradually tightened, so that the reaction force is gradually applied to the test section of the steel rail.

[0011] When the wheel-rail force is calibrated, the steps are as follows:

[0012] Step 1: The two ends and the middle part of the steel rail to be tested are held by the three clamps respectively.

[0013] Step 2: The force measuring mechanism is installed on the top surface of the middle clamp.

[0014] Step 3: The thousand jack cable is installed.

[0015] Step 4: The vertical pressure is applied to the steel rail to be tested.

[0016] The thousand jack is operated, so that the piston of the thousand jack moves upward, thereby driving the thousand jack cable to move upward; at this time, the thousand jack cable is gradually tightened along with the upward movement of the piston of the thousand jack, and the reaction force is gradually applied to the steel rail with strain gauges attached to the rail waist, so that the steel rail is subjected to the vertical force, and the force sensor signals and the rail strain signals in the process are recorded, and the vertical force calibration of the steel rail to be tested is completed.

[0017] Step 5: The horizontal pressure is applied to the steel rail to be tested.

[0018] After the vertical force calibration is completed, the direction of the force measuring mechanism is converted, the force measuring mechanism is installed to the side of the middle clamp, and the thousand jack placing cylinder is arranged transversely and perpendicularly to the length direction of the steel rail. Then, the thousand jack is operated, so that the rail bottom with strain gauges attached is subjected to the horizontal force, and the force sensor signals and the rail strain signals in the process are recorded, and the horizontal force calibration of the steel rail to be tested is completed.

[0019] Step 6: The rail strain signals are collected.

[0020] The entire calibration device is removed from the steel rail to be tested, and the vertical and horizontal strain signals of the steel rail when the train passes through the steel rail to be tested are collected.

[0021] Step 7: Data analysis and calculation

[0022] The force sensor signals and the rail strain signals collected in the calibration process are analyzed, the rail strain signals collected when the train passes through the steel rail test section are taken as the basis, the relationship between the force and the strain of the steel rail to be tested obtained in steps 5 and 6 is combined, and the horizontal and vertical force data of the steel rail when the train passes through the steel rail test section are obtained.

[0023] The advantages of the present application are as follows:

[0024] 1. Simple parts and lightweight, easy to install and carry. Currently, the wheel-rail force calibration in the railway field can only be carried out at the time point of the skylight. At the present stage, the calibration equipment is heavy, the disassembly process takes a long time, and the horizontal and vertical conversion process is complicated, which seriously restricts the efficiency of the wheel-rail force calibration. The calibration device optimizes the clamp locking mode, greatly saving the disassembly time of the device. At the same time, the way of limiting the piston stroke of the jack by the jack cable is adopted to apply a counter force to the steel rail, replacing the heavy steel beam, so that the whole assembly is more lightweight.

[0025] 2. Accurate calibration results and high reliability of test effect. In the current wheel-rail force calibration process, the force applied by the detection jack on the steel rail is detected by a pressure sensor mounted on the jack. The data transmitted by the pressure sensor is the pressure in the jack pressing process. The present application directly monitors the force between the jack and the steel rail by using a wheel-spoke type force sensor, thereby reducing the influence of external environment, human operation and other factors, making the calibration results more accurate, which has been verified in practical application.

[0026] 3. Quickly realize horizontal and vertical wheel-rail force calibration conversion. In the wheel-rail force calibration process, the horizontal and vertical wheel-rail forces need to be calibrated, and the traditional calibration method needs to use two sets of equipment to calibrate the horizontal and vertical wheel-rail forces. The present application uses a jack cable as a limiting device, which is flexible and can quickly realize horizontal and vertical conversion. Therefore, it is not necessary to use two sets of equipment for calibration, thereby reducing the number of carried equipment and improving the conversion efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a schematic view of the overall structure of the lightweight wheel-rail force calibration device of the present application.

[0028] Figure 2 It is a side view of the overall structure of the lightweight wheel-rail force calibration device of the present application.

[0029] Figure 3 It is a schematic view of the left clamping jaw structure in the lightweight wheel-rail force calibration device of the present application.

[0030] Figure 4 It is a schematic view of the right clamping jaw structure in the lightweight wheel-rail force calibration device of the present application.

[0031] Figure 5 It is a schematic view of the jack placement cylinder structure in the lightweight wheel-rail force calibration device of the present application.

[0032] Figure 6 It is a flow chart of the lightweight wheel-rail force calibration method of the present application.

[0033] 1- clamp 2- force measuring mechanism 3- jack cable

[0034] 4- Rail test section 101- Left gripper 102- Right gripper

[0035] 103-Cylinder 104-Cone 105-Locking Block

[0036] 106 - Sensor connection screw hole; 107 - Rectangular block; 201 - Force sensor

[0037] 202-Jack placement cylinder; 203-Jack; 202a-Threaded connector

[0038] 202b - Rectangular opening; 203a - Piston; 301 - Locking latch Detailed Implementation

[0039] The invention will now be further described with reference to the accompanying drawings.

[0040] The lightweight wheel-rail force calibration device of the present invention includes a clamp 1, a force measuring mechanism 2, and a jack cable 3, as shown below. Figure 1 , Figure 2 As shown.

[0041] The clamps 1 consist of three sets, named clamp A, clamp B, and clamp C, which are used to clamp the front end, middle position, and end end of the rail test section 4, respectively. The three sets of clamps 1 have identical structures, each consisting of two symmetrical jaws; as shown... Figure 3 , Figure 4 As shown, the lower inner contour of the left gripper 101 is the same as the outer contour of the left half of the rail head; the lower inner contour of the right gripper 102 is the same as the outer contour of the right half of the rail head; thus, the inner contours of the left and right grippers together form the outer contour of the rail head. The lower inner surfaces of the left gripper 101 and the right gripper 102 are respectively tightly fitted to both sides of the rail head, and the locking mechanism further achieves locking and fixing between the two and the rail head.

[0042] The locking mechanism consists of two cylinders 103 and two cones 104. The cylinders 103 are parallel to each other on the same horizontal plane and perpendicular to the length of the rail test section 4 along their axis. The ends of the two cylinders 103 are fixed to the upper part of the left gripper 101, allowing them to be designed as a single unit. A cone 104 is fixed to the front end of each of the two cylinders 103. The cone 104 is coaxial with the cylinders 103, and its bottom surface is in contact with the end surface of the cylinders 103, allowing them to be designed as a single unit. The diameter of the bottom surface of the cone 104 is larger than the diameter of the cylinder. Furthermore, the cone 104 is designed with a coaxial cross-shaped notch, which divides the cone 104 circumferentially into four equal parts.

[0043] When the left clamp jaw 101 and the right clamp jaw 102 are installed, the two cylinders 103 on the left clamp jaw 101 pass through the through holes 105 with the same inner diameter and outer diameter as the cylinders 103 on the right clamp jaw 102. During the passing process, the top end of the conical body 104 enters the inner end of the through hole 105 first. Since the diameter of the top end of the conical body 104 is smaller than that of the through hole 105, the conical body 104 can enter the through hole 105. Further, according to the characteristics of the conical body 104, during the gradual entering process, the diameter of the conical body 104 is greater than that of the through hole 105. At this time, since the designed conical body 104 has a cross-shaped notch, the diameter of the bottom surface of the conical body 104 is changed by compressing the cross-shaped space, so as to smoothly enter the through hole. After the conical body 104 completely passes through the through hole, the conical body 104 is no longer subjected to extrusion, at which time the diameter of the bottom end of the conical body 104 returns to normal. At this time, the bottom end of the conical body is attached to the outer side of the right clamp jaw B, and the locking and fixing between the left clamp jaw 101, the right clamp jaw 102 and the rail head of the rail test section are achieved. Further, in order to prevent the conical body 104 from being extruded due to excessive force of the clamp 1, causing the diameter of the conical body 104 to change and causing the left and right parts of the clamp to separate, a cross-shaped structure locking block 105 matched with the cross-shaped structure on the conical body 104 is designed to be inserted into the cross-shaped notch of the conical body 104.

[0044] The force measuring mechanism 2 is composed of a force sensor 201, a jack placing cylinder 202 and a jack 203. The force sensor 201 is fixedly installed on the top surface of the clamp B after being installed at the middle position of the rail test section 4, and is connected with the sensor connecting screw hole 106 on the top surface of the left and right clamp jaws of the clamp B by bolts. Figure 5 As shown in the figure, the jack placing cylinder 202 is a cylindrical cylinder, which is vertically arranged along the longitudinal direction of the rail test section 4, and has a threaded joint 202a coaxially designed at the bottom end, which is screwed and fixed with the center threaded hole of the force sensor 201. The jack 203 is located inside the jack placing cylinder 202, and the output end axis of the jack 203 is coaxially arranged with the jack placing cylinder 202. The opposite side wall of the above-mentioned jack placing cylinder 202 has a rectangular opening 202b, the long side of which is parallel to the axis of the jack placing cylinder 202, and the rectangular opening 202b penetrates the top edge of the jack placing cylinder 202, which is used to set the jack cable 3.

[0045] The jack cable 3 is arranged along the longitudinal direction of the rail, and is placed in the rectangular openings 202b on the opposite sides of the jack placing cylinder 202 at the top end of the jack placing cylinder 202. The two ends of the jack cable 3 pass through the through holes in the rectangular blocks 107 on the top of the left and right clamp jaws of the clamps A and C located at the left and right ends of the rail test section 4, and are fixed into a ring with the jack cable 3 through the lock buckle 301. The middle part of the jack cable 3 is in contact with the output end piston 203a of the jack 203.

[0046] The wheel-rail force calibration method of the light-weight wheel-rail force calibration device based on the above structure is as follows: Figure 6 As shown in the figure, the specific steps are as follows:

[0047] Step 1: The two ends and the middle part of the steel rail test section 4 are clamped by the three clamps 1 respectively.

[0048] Step 2: The force measuring mechanism 2 is installed on the middle clamp.

[0049] Step 3: The cable is installed.

[0050] Step 4: The vertical pressure is applied to the steel rail test section 4.

[0051] The jack 203 is operated, and the piston 203a of the jack 203 moves upward along the vertical direction of the steel rail test section 4, thereby driving the middle part of the cable 3 to move upward. Since the positions of the two ends of the cable 3 are unchanged, the cable 3 is gradually tightened with the rising of the piston 203a of the jack, and gradually applies a reaction force to the steel rail test section 4 with strain gauges attached to the rail waist position, so that the steel rail 2 is subjected to a vertical force, and the process of the force sensor 201 and the steel rail strain signal is recorded, and the vertical force calibration of the steel rail test section 4 is completed.

[0052] Step 5: The horizontal pressure is applied to the steel rail test section.

[0053] After the vertical force calibration is completed, the direction of the force measuring mechanism 2 is converted, and the force sensor 201 in the force measuring mechanism 2 is disassembled. Since the cable can be flexibly rotated in the hole on the top rectangular block 107 of the left and right clamping jaws of the clamp A and the clamp B, the force measuring mechanism 2 is rotated to the side of the left clamping jaw 101 of the middle clamp B, and the force sensor 201 is further fixed in the sensor connecting screw hole 106 on the side surface of the left clamping jaw of the clamp B by cooperation with the bolt, so that the jack placement cylinder 202 is transversely perpendicular to the long direction of the steel rail test section 4. Further, strain gauges are attached to the rail bottom position of the steel rail 4. Then the jack 203 is operated to make the steel rail test section 2 subjected to horizontal stress, and the process of the force sensor 201 and the steel rail test section 4 strain signal is recorded, and the horizontal force calibration of the steel rail test section 4 is completed.

[0054] Step 6: Collect the steel rail strain signal.

[0055] The entire calibration device is removed from the steel rail test section, and the vertical and horizontal strain signals of the steel rail when the train passes through the steel rail test section 4 are collected.

[0056] Step 7: Data analysis and calculation

[0057] The force sensor signals collected in the calibration process and the rail strain signals are analyzed, and based on the rail strain signals collected when the train passes the rail test section 4, in combination with the relationship between the stress and strain of the rail test section 4 obtained in steps 5 and 6, the rail horizontal and vertical stress data when the train passes the rail test section 4 can be obtained.

Claims

1. A lightweight wheel-rail force calibration device, characterized by: The device comprises a clamp, a force measuring mechanism and a cable; The clamp comprises end clamps for clamping the two ends of the rail test section and a middle clamp for clamping the middle part of the rail test section; the top surface and the side surface of the middle clamp are the installation positions of the force measuring mechanism, which is used to install the force measuring mechanism to exert vertical force and lateral force on the clamped rail; the clamp is composed of a left clamp jaw and a right clamp jaw; the inner side contour of the lower part of the left clamp jaw is the same as the outer contour of the left half of the rail head; the inner side contour of the lower part of the right clamp jaw is the same as the outer contour of the right half of the rail head; the inner side upper part of the left clamp jaw is designed with a cylinder along the lateral direction of the rail, and the end of the cylinder is designed with a coaxial cone; the bottom surface of the cone has a diameter larger than the diameter of the cylinder; meanwhile, the cone is designed with a cross-shaped notch to divide the circumference of the cone into four equal parts; The cylinder on the left clamp jaw passes through the through hole on the corresponding position of the right clamp jaw; during the passing process, the diameter of the cone gradually becomes larger than the inner diameter of the through hole, at which time the end of the cone is compressed by the force to make the whole cone enter the through hole; until the cone passes out of the through hole, the cone restores; at this time, the bottom end of the cone is attached to the outside of the right clamp jaw, realizing the locking and fixing between the left clamp jaw, the right clamp jaw and the rail head; after the locking and fixing between the left clamp jaw, the right clamp jaw and the rail head, the cross-shaped structure locking block matching the cross-shaped structure on the cone is inserted into the cross-shaped notch of the cone; The force measuring mechanism comprises a force sensor, a jack placement cylinder and a jack; the force sensor is installed on the middle clamp; the jack placement cylinder is coaxially fixed with the force sensor; the jack is located inside the jack placement cylinder; the opposite side walls of the jack placement cylinder have openings for setting the cable; The cable is arranged along the long direction of the rail and is placed in the openings on the opposite sides of the jack placement cylinder from the top end of the jack placement cylinder; the ring-shaped connecting ends at both ends of the cable pass through the through holes on the rectangular blocks designed on the top of the two end clamps to be connected with the rectangular blocks; and the middle part of the cable is in contact with the end piston of the jack output end; thus, by controlling the output force of the jack, the cable is gradually tightened, thereby gradually exerting the counter force on the rail test section; To exert vertical pressure on the rail to be tested: operate the jack to make the piston of the jack move upward, thereby driving the cable to run upward; at this time, the cable is gradually tightened with the upward movement of the piston of the jack, gradually exerting the counter force on the rail with strain gauges attached to the rail waist, so that the rail is subjected to vertical force, and the vertical strain signals of the force sensor and the rail during the process are recorded to complete the vertical force calibration of the rail to be tested; To exert lateral pressure on the rail to be tested: after the vertical force calibration is completed, the direction of the force measuring mechanism is changed, and the force measuring mechanism is installed to the side of the middle clamp, so that the jack placement cylinder is arranged transversely perpendicular to the long direction of the rail; then operate the jack to make the rail with strain gauges attached to the rail bottom bear lateral force, record the lateral strain signals of the force sensor and the rail during the process, and complete the lateral force calibration of the rail to be tested.

2. The light-weight wheel-rail force calibration device of claim 1, wherein: The two upper part cylinders on the inner side of the left clamp jaw are arranged in parallel with the horizontal plane.

3. The calibration method of the light-weight wheel-rail force calibration device according to claim 1, characterized in that: The specific steps are as follows: Step 1: clamp the two ends and the middle part of the rail to be tested by the three clamps; Step 2: install the force measuring mechanism on the top surface of the middle clamp; Step 3: install the cable; Step 4: Vertical pressure is applied to the rail to be tested; The jack is operated to move the piston of the jack upward, thereby driving the jack cable to run upward; at this time, the jack cable is gradually tightened as the piston of the jack rises, and gradually applies a counterforce to the rail with strain gauges attached to the rail waist, so that the rail is subjected to vertical force, and the vertical strain signals of the force sensor and the rail during the process are recorded, and the vertical force calibration of the rail to be tested is completed; Step 5: Transverse pressure is applied to the rail to be tested; After the vertical force calibration is completed, the direction of the force measuring mechanism is converted, the force measuring mechanism is installed to the side of the middle clamp, the jack cylinder is transversely perpendicular to the long direction of the rail; then the jack is operated to make the rail with strain gauges attached to the rail bottom bear transverse force, and the transverse strain signals of the force sensor and the rail during the process are recorded, and the transverse force calibration of the rail to be tested is completed; Step 6: Collecting rail strain signals; The entire calibration device is removed from the rail to be tested, and the vertical and transverse strain signals of the rail when the train passes through the rail to be tested are collected; Step 7: Data analysis and calculation The force sensor signals collected during the calibration process and the rail strain signals are analyzed, and based on the collected rail strain signals when the train passes through the rail test section, the relationship between the stress and strain of the rail to be tested obtained in steps 5 and 6 is combined to obtain the rail transverse and vertical stress data when the train passes through the rail test section.

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