Large machine precision grinding process

Abstract

The invention discloses a large-scale precision grinding process method, which belongs to the field of engineering technology, and specifically is a large-scale precision grinding process method, which includes: S1: improving the technical performance of the equipment, and the step S1 specifically includes: specifying the angle calibration cycle and conducting precision review, improving the synchronous and smooth performance of the equipment, detecting the grinding motor, detecting the grindstone, and controlling the system to check and adjust parameters; S2: grinding scheme design, and the step S2 specifically includes: designing the profile scheme, and designing the slope mode. The large-scale precision grinding process method can improve the technical status and operation accuracy of the equipment, formulate a precise grinding plan in combination with the technical performance of the grinding vehicle, solve the problem of too deep grinding marks at the starting point of grinding, solve the grinding quality problem caused by inaccurate motor lowering and large deviation in synchronization of mode conversion, and can solve the limitations of quality acceptance.

Description

Technical Field

[0001] The invention relates to the field of engineering technology, and in particular to a large-scale precision grinding process. Background Art

[0002] Large machine grinding can improve wheel-rail coupling, prevent contact fatigue, wear, corrugation and other rail diseases, repair or reduce rail surface diseases, delay the development of oblique cracks in rails, and improve train operation quality. It can extend the time for wheel repair, extend the service life and maintenance cycle of rails, and improve the economic efficiency of rail maintenance.

[0003] However, with the increasing use of large-scale rail grinding machines, the shortcomings of traditional large-scale grinding machines in terms of grinding accuracy, starting point, and conversion point have gradually emerged, mainly manifested in: the grinding equipment is in poor condition, the operation accuracy is not high, the grinding plan adopted is not formulated according to the technical performance of different grinding vehicles, input wave grinding occurs at the grinding starting point or normal grinding section, the GQI of the grinding profile does not meet the requirements, the roughness after grinding does not meet the requirements, resulting in low grinding quality, and limited quality acceptance after grinding, indicating that the current grinding methods can no longer meet market demand. Therefore, it is urgent to explore the precise grinding method of large-scale rail grinding machines, improve the construction quality of large-scale grinding machines, and form a complete and feasible plan. Summary of the invention

[0004] The main purpose of the present invention is to propose a large-scale precise grinding process method, which can improve the technical status of the equipment and the operating accuracy, formulate a precise grinding plan in combination with the technical performance of the grinding vehicle, solve the problem of too deep wear marks at the starting point of grinding, solve the grinding quality problems caused by inaccurate motor lowering and large deviation in mode conversion synchronization, and can solve the limitations of quality acceptance, solving the problems raised by the above-mentioned technical background.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] The large-scale precision grinding process includes the following steps:

[0007] S1: Improving the technical performance of the equipment, the step S1 specifically includes:

[0008] Specify angle calibration cycle and conduct accuracy review, improve equipment synchronization and smoothness performance, test grinding motor, test grinding stone, control system inspection and parameter adjustment;

[0009] S2: polishing scheme design, the step S2 specifically includes:

[0010] Design profile scheme and slope-following mode;

[0011] S3: Construction technology and method, the step S3 specifically includes:

[0012] Increase the vehicle speed during lowering, execute the lowering process along the slope, control the lowering accuracy of the motor, and control the grinding joint;

[0013] S4: Quality acceptance, the step S4 specifically includes:

[0014] Quality inspection after polishing and quality acceptance tracking.

[0015] As a preferred solution of the large-scale precision grinding process method of the present invention, the specified angle calibration cycle and accuracy review in step S1 are as follows:

[0016] Before the first construction point after each line change or after one month of continuous construction, the angle of the grinding motor should be recalibrated. After the angle calibration is completed, the angle should be verified with an inclinometer to ensure the accuracy of the actual angle.

[0017] As a preferred solution of the large-scale precision grinding process method of the present invention, the specified angle calibration cycle and accuracy review in step S1 are as follows:

[0018] Before the first construction point after each line change or after one month of continuous construction, recalibrate the angle of the grinding motor. After the angle calibration is completed, verify the angle with an inclinometer.

[0019] The improvement of the smooth synchronization performance of the equipment in step S1 is specifically as follows:

[0020] Check and confirm that the hydraulic system pressure is stable and normal, check and confirm that the hydraulic valve and hydraulic cylinder are working properly, check and prevent the fixing bolts from breaking, check and tighten the lifting cylinder and deflection cylinder sensor lines, and replace damaged or failed sensor lines;

[0021] The specific details of detecting the grinding motor in step S1 are as follows:

[0022] Check and confirm that the grinding motor is operating normally, formulate the test lowering requirements after maintenance and before operation, make adjustments when voltage deviation alarm occurs, observe the fluctuation of the vehicle motor power bar during operation, and judge the abnormality of the grinding motor;

[0023] The specific details of detecting the grinding stone in step S1 are as follows:

[0024] Ensure the normal use of grinding stones. During daily maintenance, replace grinding stones according to the amount of construction work. Check the grinding stone consumption every day and observe the operating status of the grinding motor through the grinding stone consumption.

[0025] The control system inspection and parameter adjustment in step S1 are as follows:

[0026] Check and confirm that the network communication and module functions are normal, and adjust the PID parameters of the grinding car.

[0027] As a preferred solution of the large-scale precision grinding process of the present invention, the profile design scheme in step S2 is as follows:

[0028] Obtain the actual on-site profile conditions, design a reserved error tolerance, and use motor power adjustment instead of angle conversion.

[0029] As a preferred solution of the large-scale precision grinding process of the present invention, the following details are provided for designing the slope-following mode in step S2:

[0030] The setting principle of the starting point downslope mode is as follows: the motor power is selected to correspond to the lowest power in the normal profile mode. Before lowering, the motor power is reduced to a minimum of 40% through manual control, and the motor does not grind the wheel-rail contact surface;

[0031] The setting principle of the terminal slope mode is: the motor power selection corresponds to the normal mode power, and the motor does not grind the wheel-rail contact surface.

[0032] As a preferred solution of the large-scale precision grinding process of the present invention, the vehicle speed during lowering in step S3 is increased as follows:

[0033] Increase the lowering speed from 12km / h to a set speed of 16km / h-18km / h;

[0034] The specific process of carrying out the downhill lowering in step S3 is as follows:

[0035] Starting point operation process: The grinding starting point is on a straight line and a downslope distance of 150 meters or more is reserved; after discharging the motor in the downslope mode, the motor contacts the rail for 2 seconds, and then switches to the normal mode. After the angle conversion is completed and the motor power is stable, the reduced motor power is canceled; when switching from the downslope mode to the design profile mode, keep the power at a low level, record the motor lowering mileage in the first pass and the mileage from the downslope mode to the normal mode, and then perform full coverage in the second pass, with a coverage length of 50 meters or more;

[0036] Operation process at the end point: operate to the end point, lift the grinding motor, reserve a distance of 150 meters or more for the grinding vehicle to start and go uphill, and then stop to prepare for the second grinding; after discharging the motor in the downhill mode, the motor contacts the rail for 2 seconds, and then switch to normal operation mode. After the angle conversion is completed and the motor power is stable, cancel the reduced motor power; complete the normal operation mode conversion before entering the mileage of the first grinding lifting point, and the second grinding covers the end point of the first grinding; operate to the starting point of the first grinding, and after covering the starting point position for more than 20 meters, lift the grinding motor;

[0037] The accuracy of controlling the motor lowering in step S3 is specifically as follows:

[0038] Record the actual mileage of the first motor lowering and the mileage of the designed operation mode when the downslope mode is switched to ensure that the second operation achieves full coverage at the starting point, and control the accuracy of the motor lowering on both sides and the same side, and review the GYK mileage;

[0039] The control of grinding the joint portion in step S3 is specifically as follows:

[0040] The position of the line grinding and the line grinding joint: if the starting point is connected, the starting point selects the downslope mode to switch to the normal mode, covering the previous grinding position greater than or equal to 25 meters; if the end position is connected, the end position is lifted to cover greater than or equal to 25 meters, the end position is lifted along the slope, and after the normal mode covers greater than or equal to 25 meters, it is switched to the downslope mode for lifting;

[0041] When the station is blocked, the line grinding is operated first: grinding to 300 meters away from the last set of switches in the station; the line grinding covers the line grinding traces of more than or equal to 25 meters; the line grinding is operated first: grinding to 300 meters outside the last set of switches in the station, and the line grinding covers the line grinding traces of more than or equal to 25 meters;

[0042] If the station is not blocked, the line grinding will be carried out first: grinding to 300 meters outside the signal machine; the branch grinding covers the line grinding traces greater than or equal to 25 meters;

[0043] Before grinding, the weld joints are ground with a small machine in advance;

[0044] In the restricted area of ​​turnout grinding vehicles, small machines shall grind within one month after the large machines have finished grinding;

[0045] When grinding a large slope of more than 16%, reduce the vehicle speed and reduce the power in proportion to the speed reduction;

[0046] When grinding a skylight point in a long tunnel, it only needs to be polished twice. The second polishing should be done after the dust has settled and the visibility is good after the first polishing.

[0047] As a preferred solution of the large-scale precision grinding process of the present invention, the quality inspection after grinding in step S4 is as follows:

[0048] Check and connect with the maintenance section or quality acceptance unit to confirm the quality within the starting point range, observe whether there are abnormal wear marks on the rail surface, check the quality of the starting and ending positions on the day after grinding, track the grinding stone consumption, and determine the working status of the grinding motor;

[0049] The quality acceptance tracking in step S4 is specifically as follows:

[0050] After grinding on the same day, a single-point MiniProf is used to randomly select points for acceptance. After a period of continuous operation, a continuous profiler is used to collect a section for continuous profile analysis. The equipment management unit analyzes and compares the data from the portable inspection instrument to understand the dynamic quality of the rails after grinding.

[0051] The beneficial effects of the present invention are as follows:

[0052] 1. Research on equipment aspects such as calibration cycle and accuracy review from the specified angle of the grinding vehicle, improving the synchronous and smooth performance of the equipment, testing the grinding motor, testing the grinding stone, controlling system inspection and parameter adjustment, so as to improve the technical status of the equipment and operating accuracy.

[0053] 2. Conduct research from the aspects of designing profile scheme and designing slope mode, and formulate precise grinding scheme in combination with the technical performance of the grinding vehicle.

[0054] 3. Carry out construction from the aspects of increasing the vehicle speed during lowering, executing the lowering process along the slope, controlling the lowering accuracy of the motor, and controlling the grinding joint, so as to achieve precise grinding of rails by large machines, solve the problem of too deep wear marks at the starting point of grinding, and solve the problems of inaccurate motor lowering and large deviation in mode conversion synchronization.

[0055] 4. Use continuous profiling trolley + single-point MiniProf profilometer for quality acceptance, and simultaneously carry out roughness, hardness, and equivalent taper acceptance. At the same time, quality acceptance of weak places at the starting and ending points is carried out, and the light bands on the rail surface at the starting and ending points after grinding and the alarm conditions of the added-ride instrument are tracked to solve the limitations of quality acceptance.

[0056] The precision grinding technology of this large machine can improve the technical status and operation accuracy of the equipment, formulate a precise grinding plan based on the technical performance of the grinding vehicle, solve the problem of too deep wear marks at the starting point of grinding, solve the grinding quality problems caused by inaccurate motor lowering and large deviation in mode conversion synchronization, and can solve the limitations of quality acceptance. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0058] Figure 1 It is a schematic diagram of the process of the present invention;

[0059] Figure 2 It is a schematic diagram of the rail profile grinding mode of the present invention;

[0060] Figure 3 It is a schematic diagram of the corresponding downslope mode of the starting point of the present invention;

[0061] Figure 4 This is a schematic diagram of the corresponding downhill mode of the end point lifting of the present invention;

[0062] Figure 5 It is a schematic diagram of grinding the limited grinding area of ​​the turnout according to the present invention.

[0063] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0064] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0065] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, back, etc., then the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture as shown in the accompanying drawings. If the specific posture changes, the directional indication will also change accordingly.

[0066] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0067] The present invention provides a large-scale precision grinding process method, which can improve the technical status of the equipment and the operating accuracy, formulate a precise grinding plan in combination with the technical performance of the grinding vehicle, solve the problem of too deep grinding marks at the starting point of grinding, solve the grinding quality problems caused by inaccurate motor lowering and large mode conversion synchronization deviation, and solve the limitation problem of quality acceptance;

[0068] like Figure 1 ,include:

[0069] (I) Improve equipment technical performance

[0070] 1. Specify the angle calibration cycle and conduct accuracy review

[0071] Whether the grinding motor deflection angle is accurate is directly related to whether the grinding mode can be implemented accurately. Therefore, the accuracy of the grinding motor angle must be confirmed before operation.

[0072] (1) Specify the grinding motor calibration cycle

[0073] Recalibrate the angle of the grinding motor before the first construction point after each line change or after one month of continuous construction.

[0074] (2) Grinding motor angle calibration method

[0075] ①Park the vehicle on a horizontal line. Park the grinding vehicle on a line with zero straightness, lower the grinding vehicle and make sure that the wheels of the grinding vehicle are in close contact with the surface of the rail, and connect the calibration box to the calibration box connection terminal closest to the grinding motor whose angle needs to be calibrated.

[0076] ② Take the reference zero degree. Select a surface on the grinding trolley beam that is parallel to the rail surface, wipe off the dust on the surface to remove foreign matter, turn on the inclinometer and place it on the selected plane, force it to zero, set it as the reference zero degree and keep it turned on.

[0077] ③ Select the calibration position. Select a surface parallel to the rail surface at the rocker where the grinding motor is located, wipe off the dust on the surface to remove foreign matter, and place the inclinometer.

[0078] ④Calibration operation. Enter the calibration interface on the calibration box, select the corresponding motor, grind the motor by swinging it back and forth and observe the angle value on the inclinometer until the value reaches 0, then stop swinging and press the calibration key to complete the calibration operation.

[0079] (3) Verification of grinding motor angle

[0080] After the angle calibration is completed, in order to ensure the accuracy of the actual angle, the grinding motor angle needs to be adjusted to the maximum angle of the outside and inside respectively, and the angle needs to be verified with an inclinometer. Motors with errors within the range of ±0.5 need to be recalibrated until the angle error value is within the standard range.

[0081] 2. Careful inspection and repair to improve the smooth synchronization performance of the equipment

[0082] (1) Ensure that the hydraulic system pressure is stable and normal. Insufficient hydraulic system pressure or accumulator pressure will affect the synchronization and stability of the grinding motor lifting and lowering. Therefore, the hydraulic system pressure must be checked during operation. If the pressure is not within the standard range, it must be adjusted during static maintenance. The accumulator pressure must be checked every 6 months and replenished in time if the pressure is insufficient.

[0083] ①Hydraulic system pressure standard: 10300KPa-10700KPa.

[0084] ②Accumulator pressure standard: 7240KPa-7930 KPa.

[0085] (2) Ensure that the hydraulic valves and hydraulic cylinders are working properly. The performance of the activation valve, control proportional valve and control proportional valve of the grinding motor lifting cylinder, as well as the sealing performance of the lifting cylinder and the deflection cylinder will directly affect the smoothness of the motor lifting and lowering during the operation, and the accuracy and retention of the angle deflection.

[0086] If the grinding motor is not lifted and lowered smoothly, check the corresponding activation valve, control proportional valve, deflection cylinder proportional valve, and measure the coil resistance of the hydraulic valve (the activation valve coil resistance is about 30Ω, the feed cylinder control proportional valve coil resistance is about 8.8Ω, and the deflection cylinder proportional valve resistance is about 20Ω). If the coil is damaged, replace it; if lifting and lowering or deflection is not in place during operation, check the status of the valve core, if the valve core sealing ring is damaged, replace it, if the valve core is severely worn, replace it, and if there is foreign matter contamination, clean it; check the sealing status of the hydraulic cylinder, and replace it if there is oil leakage or pressure failure.

[0087] (3) Prevent the fixing bolts from breaking. The fixing bolts must be replaced when the lifting cylinder is replaced, and the lifting cylinder fixing bolts must be fully replaced at least once a year.

[0088] (4) Operate at 5 points, check and tighten the lift cylinder and deflection cylinder sensor wires, and replace damaged or failed sensor wires. Replacement standards: sensor wire skin is broken, extension and retraction volume is empty or flashes red during operation, and sensor feedback value should be within the standard range (lift cylinder 0.26V-4.2V, deflection cylinder 0.6V-4.2V).

[0089] 3. Check the grinding motor to ensure that it operates normally

[0090] (1) Strictly check the motor's technical status during daily maintenance to ensure the grinding motor works normally.

[0091] ① Check the 600V cables of the motor and wrap or replace any damaged cables.

[0092] ② Clean or replace the stuck grinding motor guide column or seal ring. Standard: replace the seal ring when grease leaks, replace the guide column when the scratches on the guide column are too deep to fit the seal ring effectively, and clean the guide column when it cannot be replaced or dust enters the guide sleeve.

[0093] ③Test lowering requirements after maintenance is completed and before operation.

[0094] a. After each routine maintenance, try lowering it, start the motor, and adjust the swing angle to ensure that the motor can work normally.

[0095] b. Before each trip, test the rail track for 2 or more times (without starting the motor and without swinging the angle) to ensure that the motor can be lowered and lifted flexibly and the hydraulic system is preheated. After the test, check the rail surface and clean the iron ash.

[0096] c. Use dust covers on the guide columns to reduce dust accumulation that affects lubrication and causes motor jamming. Replace them in time if damaged.

[0097] ③Replace the abnormal grinding motor.

[0098] a. For motors that short-circuit and trip during operation, the insulation resistance of the motor stator winding to the housing should be no less than 10MΩ.

[0099] b. The rated current of the motor is 28.4A, the no-load current is about 11.5A, and the current value during operation is about 17-22A.

[0100] c. Overload is not allowed when the motor is running continuously. There should be no abnormal noise or vibration when the motor is running under load, and the bearing temperature should not exceed 110℃.

[0101] d. The flange of the motor swings obviously when shaken by hand, and there should be no rotating sound when the motor stops.

[0102] (2) Check the working condition of the 600V generator set. The power generation voltage should be stable within the range of 580-585V. When the voltage deviation alarm sounds, it should be adjusted in time to ensure the stability of the motor working voltage.

[0103] (3) During operation, observe the fluctuation of the vehicle motor power bar. If the power bar of an individual motor continues to fluctuate with a large amplitude or reaches the top, stop the motor.

[0104] (4) It is stipulated that no more than 5 motors shall be out of service in the whole vehicle. When the number exceeds the limit and affects the grinding quality, the mode shall be adjusted according to the actual use of the grinding motors to ensure the grinding quality.

[0105] 4. Check the grindstone to ensure normal operation

[0106] (1) During routine maintenance, replace the grinding stone according to the construction workload (grinding stone consumption is about 0.4-0.6mm / km) to reduce the situation where the motor is stopped due to insufficient grinding stone during operation.

[0107] (2) Check that the grinding stone has no falling pieces, no through cracks, no falling wrapped fibers, no threaded holes that do not match the bolts smoothly, and no uneven surfaces.

[0108] (3) Check that the grinding stone consumption is normal and there is no bluing phenomenon when the speed and power are normally matched.

[0109] 5. Control system inspection and parameter adjustment

[0110] (1) Network communication and module functions are normal.

[0111] ①Clear the dust attached to the control module every day.

[0112] ② Check the status of the data lines of each interface of each control module to confirm that the module data is transmitted normally and the data line connections are tight.

[0113] ③Replace the damaged or short-circuited data cable, and replace the control module with a short-circuited interface.

[0114] ④ During operation, observe the temperature of the communication module. When the temperature exceeds 80℃, stop the operation as needed to cool the module to prevent the module from overheating and stopping working.

[0115] (2) Appropriately adjust the control system parameters. The PID control of the grinding machine is divided into two stages. The first stage is the motor decentralization: the PWM value is mainly used for regulation. The second stage is the operation stage, and the PI value is mainly used for regulation. Since poor I value regulation will lead to system instability, the P value is mainly adjusted.

[0116] ①The first stage is to adjust the PWM value.

[0117] The fast lowering and slow lowering functions of a grinding machine are usually achieved through PWM (Pulse Width Modulation) technology. The PWM value determines the average power received by the motor feed cylinder, thereby controlling the speed and force of the motor lowering. The following is a general method of how to set different PWM values ​​for fast lowering and slow lowering:

[0118] a. Determine the PWM range: First, you need to understand the PWM signal range of the grinding car motor controller. This range is 10% (no output) to 50% (maximum output).

[0119] b. Fast lowering PWM value setting: For fast lowering, it is usually necessary to set the PWM value to a higher range to provide enough power to quickly lower the grinding vehicle. For example, the PWM value can be set between 38% and 42%, and the fast lowering time can be controlled between 200-650ms. When setting, ensure that the fast lowering speed is within a safe range and will not cause damage to the equipment.

[0120] c. "Slow lowering PWM value setting: For slow lowering, the PWM value should be set in a lower range to reduce the power output of the motor and achieve smooth and slow lowering. Normally, the PWM value can be set between 32% and 38%, but this needs to be adjusted according to the actual situation of the motor and the desired lowering speed. In the slow lowering mode, special attention should be paid to maintaining sufficient control accuracy to prevent too fast or too slow lowering speed.

[0121] d. Test and adjust: After setting the PWM value, actual test operation should be carried out to verify whether the lowering speed of the grinding vehicle meets the expectations. According to the test results, the PWM value can be fine-tuned until the optimal one that meets the actual use needs is found.

[0122] ②The second stage is to adjust the P value.

[0123] At the beginning, you can adjust the P value based on the initial value of P, such as P = 0.01, observe the response of the system, and gradually increase the P value until the system starts to oscillate. Then, slightly reduce the P value to make the system run stably in the critical stable state. Note: For imported car PID, the P value is adjusted in the range of 0.01-0.1, and for domestic cars equipped with self-lubricating guide columns, it is 0.01-0.03 (because the resistance of the self-lubricating guide column is greater than that of butter lubrication and the response is slow, it is recommended to adjust the P value below 0.02).

[0124] a. Observe system response: When adjusting PID parameters, always observe the system response. Ideally, monitor the feed pressure data of each grinding motor to compare with the target value. Ensure that the system can quickly and accurately reach the target value and maintain stable operation.

[0125] b. Record and observe: Record the system response and rail surface polishing effect after each PID parameter adjustment. This helps analyze the impact of parameters on system performance and provides a basis for subsequent adjustments and optimizations.

[0126] ③Notes:

[0127] a. Avoid over-adjustment: Do not adjust the PID parameters drastically at one time, but make fine adjustments gradually.

[0128] b. Consider system characteristics: Different grinding machines and working environments may have different sensitivities to PID parameters, so they need to be adjusted according to actual conditions.

[0129] c. Pay attention to safety: When adjusting PID parameters, ensure that the grinding machine operates within a safe range to avoid accidents.

[0130] Through the above steps, the PID parameters of the grinding car can be gradually adjusted to achieve better system performance and stability. Please note that the adjustment of PID parameters may need to be adjusted and optimized according to the specific equipment and application, so in actual application, more experience and experiments may be required to determine the best parameter settings.

[0131] (II) Polishing scheme design

[0132] 1. Design a silhouette plan, such as Figure 2

[0133] (1) For key polishing areas, a continuous profiler should be used to collect the profile to fully understand the actual situation of the on-site profile and improve the pertinence and effectiveness of the polishing plan design.

[0134] (2) The mode design should take into account the fault tolerance rate to avoid the failure to cover certain angles due to the failure of certain motors to grind.

[0135] (3) The mode design should try to replace angle conversion with motor power adjustment to reduce the profile mutation points.

[0136] 2. Design a slope-oriented model

[0137] (1) The principle of setting the starting point downslope mode is as follows: the motor power is selected to correspond to the lowest power in the normal profile mode. Before lowering, the motor power is reduced to the minimum (40%) through manual control. The motor does not grind the wheel-rail contact surface (the downslope profile mode angle is -10° to -5° on the outside and 12° to 45° on the inside). Figure 3 .

[0138] (2) The setting principle of the end point slope mode is: the motor power selection corresponds to the normal mode power, and the motor does not grind the wheel-rail contact surface (the slope profile mode angle is -10° to -5° on the outside and 12° to 45° on the inside). Figure 4 .

[0139] (III) Construction technology and method

[0140] 1. Increase the speed of the vehicle during lowering

[0141] (1) The amount of cutting during lowering is related to the vehicle speed during lowering and the contact area between the grinding stone and the rail. The contact area between the grinding stone and the rail changes with the grinding angle. Since the grinding angle is fixed, the contact area between the grinding stone and the rail is also fixed.

[0142] (2) The higher the vehicle speed, the smaller the amount of cutting. Based on this characteristic, in order to reduce the amount of cutting during lowering, the lowering speed was increased from the traditional 12km / h to a set speed (16km / h-18km / h).

[0143] 2. Execute the downhill decentralization process

[0144] (1) Starting point operation process

[0145] ① The starting point of grinding should be selected on a straight line and a sufficient distance along the slope (greater than or equal to 150 meters) should be reserved to ensure that it is switched to normal mode before entering the curve and the motor power is stable to avoid the formation of periodic wear marks in the curved section.

[0146] ② After discharging the motor in the slope-following mode, the motor will contact the rail for about 2 seconds, and then immediately switch to normal mode (control the slope-following distance within 10-15 meters). After the angle conversion is completed and the motor power is stable (the time is controlled within 3-5 seconds), cancel the manually reduced motor power. When switching from the slope-following mode to the design profile mode, the power will be kept at a low power, avoiding the top of some grinding motor power bars.

[0147] ③ Record the mileage of the first motor lowering and the mileage of converting the downslope mode to the normal mode (the equipment management unit shall mark the conspicuous part of the line after the first grinding). A second pass is required for full coverage, and the coverage length shall be greater than or equal to 50 meters.

[0148] (2) End point operation process

[0149] ① When the operation reaches the end point, directly lift the grinding motor to ensure that there is enough distance for the grinding vehicle to start and go down the slope (greater than or equal to 150 meters), then stop the machine and prepare for the second grinding.

[0150] ②For the decentralization process, please refer to point ② of (2) the starting point operation process.

[0151] ③ Before entering the first grinding lifting point mileage, complete the normal operation mode conversion (the coverage distance is controlled within the range of 10-20 meters) to ensure that the second grinding covers the end point of the first grinding.

[0152] ④ After the operation reaches the starting point of the first pass and the starting position is covered for more than or equal to 20 meters, directly lift the grinding motor (if the motor power is unstable and the lifting is not flexible, it can be lifted along the slope, which can effectively solve the periodic scratches on the wheel-rail contact surface caused by poor vehicle conditions. The principle of setting the end point along the slope mode is: the motor power selection corresponds to the normal profile mode power, and the angle is -10° to -5° on the outside and 12° to 45° on the inside).

[0153] ⑤ When grinding multiple times, the starting and ending positions of each grinding should be staggered by more than or equal to 10 meters to avoid sudden changes in the profile. The starting point must use the slope mode.

[0154] 3. Control the motor lowering accuracy

[0155] (1) During the operation, the actual mileage of the motor being lowered in the first pass and the mileage of the designed operation mode when switching to the slope mode must be recorded to ensure that the second pass of the operation achieves full coverage of the starting point, and strengthen the monitoring of the motor current and power bar fluctuations to grasp the motor operation status in real time.

[0156] (2) The distance difference between the first grinding motors on both sides is controlled within 1 meter; the distance between the first grinding motor and the last grinding motor on the vehicle is controlled within 3 meters.

[0157] (3) Carefully check the GYK mileage during the polishing process to ensure that the error between the GYK mileage and the ground mileage is less than or equal to 20 meters to achieve accurate conversion and coverage.

[0158] 4. Control the grinding joint

[0159] (1) When the time interval between the track grinding and the turnout grinding is close, the track grinding should be arranged first, and then the turnout grinding, and the coverage control of the track-turnout joint should be done well.

[0160] (2) The position of the wire grinder and the wire grinder joint: If the starting point is connected, the starting point selects the slope mode and switches to the normal mode, covering the previous grinding position greater than or equal to 25 meters; if the end point is connected, the end point is directly lifted to cover greater than or equal to 25 meters. The end point is lifted along the slope, and the normal mode needs to cover greater than or equal to 25 meters before switching to the slope mode.

[0161] (3) When the station is blocked, the line grinding should be operated first: grinding should be carried out to 300 meters away from the last set of switches in the station; the turnout grinding (preferably using double-machine reconnection integrated through grinding) should cover the line grinding traces greater than or equal to 25 meters. The turnout grinding should be operated first: grinding should be carried out to 300 meters outside the last set of switches in the station, and the line grinding should cover the line grinding traces greater than or equal to 25 meters.

[0162] (4) If the station is not blocked, the line grinding shall be carried out first: grinding shall be carried out to 300 meters outside the signal machine; the branch grinding shall cover the line grinding marks greater than or equal to 25 meters.

[0163] (5) Before grinding, the weld joint should be ground with a small machine in advance, and the weld straightness should be ground to 0.2mm / 1m or less.

[0164] (6) Obstacle distance control. Obstacles include infrared rays, 5T equipment, rubber walking boards, etc. In principle, they must be removed before operation. If they cannot be removed, the track grinding vehicle is controlled by jumping 100 meters before and after, and the switch grinding vehicle will grind within a 100-meter range. The rail temperature regulator is also controlled by jumping 100 meters before and after, and the switch grinding vehicle will grind within a 100-meter range.

[0165] (7) In the turnout grinding restricted area, when the grinding angle is less than or equal to +5°, the area from the clear distance of 100mm between the two adjacent rails of the straight side strand behind the fork (point G) to 100mm before the throat (point E), and from the clear distance of 100mm between the point rail and the stock rail (point D) to the tip of the point rail (point B) shall not be ground. When the grinding angle is less than +5°, the area from the top width of 50mm at the fork (point F) to 100mm before the throat (point E), and from the top width of 50mm at the point rail (point C) to the tip of the point rail (point B) shall not be ground. Figure 5 .

[0166] (8) In areas where turnout grinding vehicles are restricted, the maintenance section should arrange for a small machine to perform grinding in a timely manner (generally within one month after the large machine has finished grinding).

[0167] 5. Grinding control in special areas, as shown in Table 1

[0168] (1) When grinding on a large slope (over 16%), it is advisable to reduce the vehicle speed and reduce the power in proportion to the speed reduction to avoid excessive grinding and cutting.

[0169] (2) Speed ​​control of two machines on different slopes (the speed can be appropriately increased after power modification).

[0170] Table 1 Data table of corresponding speeds at different slopes

[0171] Ramp(‰) 0-15 16-18 19-24 25-30 31-33 Speed ​​(km / h) 18 and above 14 12 10 8

[0172] (3) Reduce the speed and reduce the power synchronously, as shown in Table 2

[0173] Table 2 Data table of corresponding motor power reduction when reducing vehicle speed

[0174]

[0175] (4) To prevent the impact of grinding dust on equipment performance and operational safety, in principle, a skylight point should only be ground twice for long tunnels, and the second grinding should be carried out after the dust from the first grinding has settled and the line of sight is good.

[0176] (IV) Quality acceptance

[0177] 1. Quality inspection after polishing

[0178] (1) Contact the maintenance section or quality inspection unit (Material General Manager or Railway Department) to confirm the quality within the first 500 meters of grinding and observe whether there are any abnormal wear marks on the rail surface.

[0179] (2) The person in charge of construction on that day must, after grinding is completed, use the time to remove the vehicle and knock off the slag to check on foot to confirm the quality of the starting and ending points. The inspection distance must be greater than or equal to 300 meters. If periodic wear marks are found, the person in charge must promptly contact the equipment management unit and the quality acceptance unit.

[0180] (3) Grinding stone consumption tracking: According to the grinding stone consumption level on site (grinding stone consumption 0.4-0.6mm / pass-kilometer), the working status of the grinding motor is judged.

[0181] 2.Quality acceptance tracking

[0182] (1) After grinding on the same day, use the single-point MiniProf to randomly select points for acceptance. After a period of continuous operation, a continuous profiler should be used to collect a section (about 10km) for continuous profile analysis to verify the quality after grinding.

[0183] (2) The equivalent taper after grinding is 0.08-0.35, the hardness of the rail surface shall not be higher than 50HB of the adjacent parent material surface, and the roughness of the grinding surface shall not be greater than 10μm.

[0184] (3) The equipment management unit marks the starting point and tracks its changes in one month, three months, six months, etc., to understand the change pattern of the weak point at the starting point. Use a small machine to repair the periodic wear marks and the areas with excessive valley depth in a timely manner.

[0185] (4) Before and after grinding, the equipment management unit should promptly analyze and compare the data from the portable inspection instrument to understand the dynamic quality of the rails after grinding.

[0186] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. Large machine precision grinding process, characterized by: The steps include: S1: Improving the technical performance of the equipment, the step S1 specifically includes: Specify angle calibration cycle and conduct accuracy review, improve equipment synchronization and smoothness performance, test grinding motor, test grinding stone, control system inspection and parameter adjustment; S2: polishing scheme design, the step S2 specifically includes: Design profile scheme and slope-following mode; S3: Construction technology and method, the step S3 specifically includes: Increase the vehicle speed during lowering, execute the lowering process along the slope, control the lowering accuracy of the motor, and control the grinding joint; S4: Quality acceptance, the step S4 specifically includes: Quality inspection after polishing and quality acceptance tracking; The specific details of increasing the vehicle speed during lowering in step S3 are as follows: Increase the lowering speed from 12km / h to a set speed of 16km / h-18km / h; The specific process of carrying out the downhill lowering in step S3 is as follows: Starting point operation process: The grinding starting point is on a straight line and a downslope distance of 150 meters or more is reserved; after discharging the motor in the downslope mode, the motor contacts the rail for 2 seconds, and then switches to the normal mode. After the angle conversion is completed and the motor power is stable, the reduced motor power is canceled; when switching from the downslope mode to the design profile mode, keep the power at a low level, record the motor lowering mileage in the first pass and the mileage from the downslope mode to the normal mode, and then perform full coverage in the second pass, with a coverage length of 50 meters or more; Operation process at the end point: operate to the end point, lift the grinding motor, reserve a distance of 150 meters or more for the grinding vehicle to start and go uphill, and then stop to prepare for the second grinding; after discharging the motor in the downhill mode, the motor contacts the rail for 2 seconds, and then switch to normal operation mode. After the angle conversion is completed and the motor power is stable, cancel the reduced motor power; complete the normal operation mode conversion before entering the mileage of the first grinding lifting point, and the second grinding covers the end point of the first grinding; operate to the starting point of the first grinding, and after covering the starting point position for more than 20 meters, lift the grinding motor; The accuracy of controlling the motor lowering in step S3 is specifically as follows: Record the actual mileage of the first motor lowering and the mileage of the designed operation mode when the downslope mode is switched to ensure that the second operation achieves full coverage at the starting point, and control the accuracy of the motor lowering on both sides and the same side, and review the GYK mileage; The control of grinding the joint portion in step S3 is specifically as follows: The position of the line grinding and the line grinding joint: if the starting point is connected, the starting point selects the downslope mode to switch to the normal mode, covering the previous grinding position greater than or equal to 25 meters; if the end position is connected, the end position is lifted to cover greater than or equal to 25 meters, the end position is lifted along the slope, and after the normal mode covers greater than or equal to 25 meters, it is switched to the downslope mode for lifting; When the station is blocked, the line grinding is operated first: grinding to 300 meters away from the last set of switches in the station; the line grinding covers the line grinding traces of more than or equal to 25 meters; the line grinding is operated first: grinding to 300 meters outside the last set of switches in the station, and the line grinding covers the line grinding traces of more than or equal to 25 meters; If the station is not blocked, the line grinding will be carried out first: grinding to 300 meters outside the signal machine; the branch grinding covers the line grinding traces greater than or equal to 25 meters; Before grinding, the weld joints are ground with a small machine in advance; In the restricted area of ​​turnout grinding vehicles, small machines shall grind within one month after the large machines have finished grinding; When grinding a large slope of more than 16%, reduce the vehicle speed and reduce the power in proportion to the speed reduction; When grinding a skylight point in a long tunnel, it only needs to be polished twice. The second polishing should be done after the dust has settled and the visibility is good after the first polishing.

2. The large machine precision grinding process method according to claim 1 is characterized in that: The specific details of the prescribed angle calibration period and accuracy review in step S1 are as follows: Before the first construction point after each line change or after one month of continuous construction, recalibrate the angle of the grinding motor. After the angle calibration is completed, verify the angle with an inclinometer. The improvement of the smooth synchronization performance of the equipment in step S1 is specifically as follows: Check and confirm that the hydraulic system pressure is stable and normal, check and confirm that the hydraulic valve and hydraulic cylinder are working properly, check and prevent the fixing bolts from breaking, check and tighten the lifting cylinder and deflection cylinder sensor lines, and replace damaged or failed sensor lines; The specific details of detecting the grinding motor in step S1 are as follows: Check and confirm that the grinding motor is operating normally, formulate the test lowering requirements after maintenance and before operation, make adjustments when voltage deviation alarm occurs, observe the fluctuation of the vehicle motor power bar during operation, and judge the abnormality of the grinding motor; The specific details of detecting the grindstone in step S1 are as follows: Ensure the normal use of grinding stones. During daily maintenance, replace grinding stones according to the amount of construction work. Check the grinding stone consumption every day and observe the operating status of the grinding motor through the grinding stone consumption. The control system inspection and parameter adjustment in step S1 are as follows: Check and confirm that the network communication and module functions are normal, and adjust the PID parameters of the grinding car.

3. The large machine precision grinding process method according to claim 1 is characterized in that: The profile design scheme in step S2 is specifically as follows: Obtain the actual on-site profile conditions, design a reserved error tolerance, and use motor power adjustment instead of angle conversion.

4. The large machine precision grinding process method according to claim 1 is characterized in that: The following details are provided in step S2 regarding the slope-following mode: The setting principle of the starting point downslope mode is as follows: the motor power is selected to correspond to the lowest power in the normal profile mode. Before lowering, the motor power is reduced to a minimum of 40% through manual control, and the motor does not grind the wheel-rail contact surface; The setting principle of the terminal slope mode is: the motor power selection corresponds to the normal mode power, and the motor does not grind the wheel-rail contact surface.

5. The large machine precision grinding process method according to claim 1 is characterized in that: The post-polishing quality check in step S4 is as follows: Check and connect with the maintenance section or quality acceptance unit to confirm the quality within the starting point range, observe whether there are abnormal wear marks on the rail surface, check the quality of the starting and ending positions on the day after grinding, track the grinding stone consumption, and determine the working status of the grinding motor; The quality acceptance tracking in step S4 is specifically as follows: After grinding on the same day, a single-point MiniProf is used to randomly select points for acceptance. After a period of continuous operation, a continuous profiler is used to collect a section for continuous profile analysis. The equipment management unit analyzes and compares the data from the portable inspection instrument to understand the dynamic quality of the rails after grinding.

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