A method for calibrating the performance of an accelerated polishing machine

Abstract

The invention discloses a method for calibrating the performance of an accelerated polishing machine, comprising the following steps: selecting two standard samples that have not undergone a polishing test and have been measured, installing the standard samples at positions 1 and 8 of a road wheel respectively, with the sides of the standard samples with marks facing outward, and installing test pieces or simulated test pieces at other positions; installing a rubber wheel marked with C on an adjustment arm, and loading No. 30 brown corundum into a sand storage hopper; adjusting various parameters of the accelerated polishing machine to meet requirements; when the number of revolutions reaches n1, the accelerated polishing machine automatically stops, the road wheel and the test piece are cleaned, and all residual brown corundum is removed; the rubber wheel marked with C is removed and replaced with a rubber wheel marked with X, and No. 280 green silicon carbide is loaded into the sand storage hopper; when the number of revolutions reaches n2, the accelerated polishing machine automatically stops, the standard sample is removed, the road wheel and the test piece are cleaned, and all residual green silicon carbide is removed; and the polishing values ​​of the two standard samples polished by the accelerated polishing machine are respectively measured.

Description

Technical Field

[0001] The present invention relates to the technical field of accelerated polishing machines, and in particular to a method for calibrating the performance of an accelerated polishing machine. Background Art

[0002] According to statistics from the National Bureau of Statistics, by the end of 2020, my country's total highway mileage reached 5.1981 million kilometers, of which 161,000 kilometers were expressways, ranking first in the world. Furthermore, according to relevant statistics, traffic accidents have averaged over 200,000 per year in my country over the past five years, resulting in significant loss of life and property. This is largely due to improper driving behavior by drivers themselves, but also to the declining skid resistance of highway pavements over time.

[0003] The skid resistance of a pavement is primarily determined by two factors: gradation determines the road's macrostructure, while aggregate surface roughness determines its microstructure. The polishing value test is a widely recognized and representative testing method for examining the microroughness of the pavement surface and assessing whether an aggregate meets the requirements for an anti-skid wearing course in asphalt pavements. Accelerated polishing machines are one of the key instruments used in polishing value testing.

[0004] At present, the performance verification of accelerated grinding machines is mainly carried out in accordance with the relevant specifications of JJG (Traffic) 054-2009 "Verification Procedures for Accelerated Grinders". However, there are certain limitations in the actual verification implementation:

[0005] (1) Certified standard test pieces are not easy to obtain;

[0006] (2) The materials used in the certified standard specimens from different sampling sites have certain differences in various properties, which to some extent affect the final test results;

[0007] (3) The verification process is cumbersome, takes a long time, and the verification success rate is not high. Summary of the Invention

[0008] To this end, the present invention provides a method for calibrating the performance of an accelerated polishing machine to solve the above-mentioned problems in the prior art.

[0009] In order to achieve the above object, the present invention provides the following technical solutions:

[0010] According to a first aspect of the present invention, a method for calibrating the performance of an accelerated polishing machine includes the following steps:

[0011] Step S100: Select two standard samples that have not been subjected to the polishing test and have been measured, and install the standard samples at road wheel positions 1 and 8 respectively, with the side of the standard sample with the mark facing outward, and install test pieces or simulated test pieces at other positions;

[0012] Step S200: Install the rubber wheel marked C on the adjustment arm and load No. 30 brown corundum into the sand storage hopper;

[0013] Step S300, adjusting various parameters of the accelerated polishing machine to meet the requirements;

[0014] Step S400: Set the number of revolutions to n1 on the control panel, and press the power switch to start the accelerated grinder.

[0015] Step S500: When the number of revolutions reaches n1, the acceleration grinder automatically stops, the road wheel and the test piece are cleaned, and all residual brown corundum is removed;

[0016] Step S600: Remove the rubber wheel marked with C and replace it with the rubber wheel marked with X, and load No. 280 green silicon carbide into the sand storage hopper;

[0017] Step S700: Set the number of revolutions to n2 on the control panel, and press the power switch to start the accelerated grinder.

[0018] Step S800: When the number of revolutions reaches n2, the acceleration grinder automatically stops, the standard sample is taken out, the road wheel and the test piece are cleaned, and all residual green silicon carbide is removed;

[0019] Step S900: measuring the polishing values ​​of two standard samples polished by an accelerated polishing machine.

[0020] Furthermore, before step S100 , the method further includes: controlling the room temperature to be 20° C.±2° C. 2 hours before the calibration and during the calibration process.

[0021] Furthermore, n1 in step S400 and step S500 is 3200.

[0022] Furthermore, step S400 also includes simultaneously starting the coarse sand speed control button and the water flow meter.

[0023] Furthermore, n2 in step S700 and step S800 is 6400.

[0024] Furthermore, step S700 also includes simultaneously starting the fine sand speed regulating button and the water flow meter.

[0025] Furthermore, the formula for calculating the difference between the standard sample before and after polishing in step S900 is:

[0026] Δ=PSV 0i PSV1i ;

[0027] Where:

[0028] Δ is the difference between the polishing values ​​of the standard sample before and after polishing;

[0029] PSV 1i is the polishing value of the standard sample after polishing;

[0030] PSV 0i It is the polishing value before polishing value of standard sample.

[0031] Furthermore, the polishing value of the polished standard sample was tested and compared with the PSV value before polishing to eliminate the introduction of polishing value measurement uncertainty caused by the wear of the rubber sheet of the high-precision pendulum friction coefficient measuring device during the same test process.

[0032] Furthermore, the difference in PSV between the standard samples before and after the polishing test should be 7 to 13, which means that the performance test of the accelerated polishing machine has passed.

[0033] The present invention has the following advantages: compared with the original verification method, the raw materials of the new standard specimens used in the improved method are easier to obtain, which effectively solves the bottleneck problem of the current standard material production. In addition, the compressive strength of the new standard specimens is better than that of the original standard specimens, which can reduce the phenomenon of specimen breakage during the test. Based on the new standard specimens, the use of the improved verification method can reduce the verification process that originally took a day or even several days to complete to a few hours, and at the same time can greatly improve the success rate of the verification. The original verification method is improved, in which the measurement results of PSV are used to directly determine the verification results of the performance of the accelerated polishing machine, and the difference in PSV of the standard specimens before and after the polishing test is used for judgment, thereby eliminating the influence of uncertainty introduced by the measurement process of the pendulum friction coefficient meter. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely illustrative, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0035] The structures, proportions, sizes, etc. illustrated in this specification are intended only to complement the contents disclosed herein and to facilitate understanding and reading by persons familiar with the art. They are not intended to limit the conditions under which the present invention may be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportions, or adjustments in sizes, without affecting the efficacy and objectives of the present invention, shall still fall within the scope of the technical contents disclosed herein.

[0036] Figure 1 A flowchart of a method for calibrating the performance of an accelerated polishing machine provided in some embodiments of the present invention. DETAILED DESCRIPTION

[0037] The following describes the implementation of the present invention using specific embodiments. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. Obviously, the embodiments described are only a portion of the present invention, not all of it. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0038] Accelerated grinding machine verification:

[0039] A. The room temperature should be controlled at 20℃±2℃ 2h before and during the test.

[0040] B. Select two standard samples that have not been subjected to the polishing test and have been measured. Install the standard samples at the road wheel positions 1 and 8 respectively, with the marked side of the standard sample facing outward, that is, the running direction of the rubber wheel on the polishing machine is consistent with the running direction of the slippery block on the standard sample. Install test pieces or simulated test pieces at other positions;

[0041] C. Install the rubber wheel marked C on the adjusting arm and put No. 30 brown corundum into the sand storage hopper;

[0042] D. Adjust the parameters of the accelerated grinder to meet the requirements;

[0043] E. Set the speed to 3200 on the control panel, press the power switch to start the accelerated grinder, and at the same time start the coarse sand speed adjustment button and water flow meter;

[0044] F. When the number of revolutions reaches 3200, the acceleration grinder automatically stops, and the road wheel and test piece are cleaned to remove all residual brown corundum;

[0045] G. Remove the rubber wheel marked C and replace it with the rubber wheel marked X, and load No. 280 green silicon carbide into the sand storage hopper;

[0046] H. Set the speed to 6400 on the control panel, press the power switch to start the accelerated grinder, and start the fine sand speed adjustment button and water flow meter at the same time;

[0047] I. When the number of revolutions reaches 6400, the accelerated polishing machine automatically stops, the standard sample is removed, the road wheel and the test piece are cleaned, and all residual green silicon carbide is removed;

[0048] J. Measure the polishing values ​​of two standard samples after being polished by an accelerated polishing machine, and calculate the difference between the standard samples before and after polishing according to the following formula.

[0049] Δ=PSV 0i PSV 1i ;

[0050] Where:

[0051] Δ is the difference between the polishing values ​​of the standard sample before and after polishing;

[0052] PSV 1i is the polishing value of the standard sample after polishing;

[0053] PSV 0i It is the polishing value before polishing value of standard sample.

[0054] Using a new, improved method for accelerated polishing machine calibration, a new standard sample is used, first with coarse sandblasting at 3200 rpm and then with fine sandblasting at 6400 rpm. The polishing value of the polished standard sample is compared with the PSV value before polishing to eliminate the uncertainty in polishing value measurement caused by wear of the rubber sheet of the high-precision pendulum friction coefficient measuring device during the same test. The difference in PSV between the standard sample before and after the polishing test should be 7 to 13, indicating that the accelerated polishing machine has passed the performance calibration.

[0055] Traceability of the polishing quality value of the accelerated polishing machine: The polishing value of the specimen is measured by a high-precision pendulum friction coefficient measuring device. Therefore, the accuracy of the performance test of the accelerated polishing machine is evaluated with the help of a high-precision pendulum friction coefficient measuring device.

[0056] According to national metrology standards, the standards for angles, lengths, and masses involved in the calibration of accelerated grinders are shown in Table 1.

[0057] Table 1 National measurement standards for angles, lengths and masses.

[0058]

[0059] The uncertainty assessment of the polishing value measurement results of the standard sample during the performance verification of the accelerated polishing machine is as follows:

[0060] U=1.2, k=2.

[0061] The maximum permissible error of the PSV difference between the pre- and post-polishing values ​​of the accelerated polishing machine's polishing value qualification evaluation standard sample is 10 ± 3. This indicates that the test results of the improved method for testing the performance of the accelerated polishing machine are accurate and reliable.

[0062] Advantages of the improved method for testing accelerated polishing machines: Compared with the original testing method, the advantages of the improved method for testing the performance of accelerated polishing machines are shown in Table 2.

[0063] Table 2 Comparison results of accelerated grinding machine calibration methods.

[0064]

[0065] Compared with the original verification method, the raw materials of the new standard samples used in the improved method are easier to obtain, which effectively solves the current bottleneck problem of standard material production. In addition, the compressive resistance of the new standard samples is better than that of the original standard samples, which can reduce the occurrence of specimen breakage during the test. Based on the new standard samples, the use of the improved verification method can reduce the verification process that originally took a day or even several days to complete to a few hours, and at the same time can greatly improve the success rate of the verification. The original verification method has been improved, and the method of using the PSV measurement results to directly determine the verification results of the accelerated polishing machine performance has been improved. Instead, the difference in PSV of the standard samples before and after the polishing test is used for judgment, thereby eliminating the influence of uncertainty introduced by the measurement process of the pendulum friction coefficient measuring device.

[0066] In order to verify the effectiveness and feasibility of the improved method for the performance verification of the accelerated grinding machine proposed in this paper, six certified standard samples and new standard samples specified in JJG (Jiaotong) 054-2009 "Verification Procedure for Accelerated Grinders" were used to verify the performance of the three accelerated grinding machines according to the corresponding verification process. The verification results are as follows.

[0067] The test environment was set at 22°C and 85% relative humidity. Three accelerated polishing machines (1#, 2#, and 3#) were selected for calibration, along with a pendulum-type friction coefficient measuring device that met the maximum allowable error. Before the polishing tests, the polishing values ​​(PSVs) of the standard sample made of epidote-derived andesite specified in JJG (Traffic) 054-2009 and the new standard sample proposed in this paper, composed primarily of 75% to 85% alumina ceramic, 15% to 25% sand (SiO2), and a binder, were measured. The average values ​​of the measurement results are shown in Table 3.

[0068] Table 3. Average PSV measurement results of specimens before polishing test.

[0069]

[0070] First, a standard sample made of epidote andesite was used to calibrate the accelerated grinding machine according to the JJG (Traffic) 054-2009 accelerated grinding machine calibration procedure. Two parallel tests were performed. After the test, the PSV of the specimen was measured using a pendulum friction coefficient measuring device. The measurement results are shown in Table 4.

[0071] Table 4. PSV measurement results of epidote-induced andesite standard samples.

[0072]

[0073] As can be seen from Table 4, according to the relevant provisions of JJG (Jiaotong) 054-2009 "Accelerated Polishing Machine Verification Procedure", the PSV measurement results of the standard samples of the three accelerated polishing machines all meet the specified range of 46 to 52. Therefore, it can be determined that the overall accuracy of the three accelerated polishing machines is qualified.

[0074] Table 5 PSV measurement results of new standard sample polishing value using improved method.

[0075]

[0076] The three accelerated grinding machines were then calibrated using the improved method proposed in this article, following the whole-machine accuracy verification procedures. Using the newly prepared standard samples, two parallel tests were conducted, with coarse sandblasting at 3200 rpm and fine sandblasting at 6400 rpm. After the tests, the PSV values ​​of the new standard samples were measured. The results are shown in Table 5. It can be seen that, following the process described in this article's improved accelerated grinding machine verification method, the PSV values ​​of the new standard samples for the three accelerated grinding machines ranged from 61 to 64.

[0077] The results of calculating the difference between the average PSV of the polished specimens in the parallel tests in Tables 4 and 5 and the PSV of the specimens before polishing are shown in Table 6.

[0078] Table 6 compares the PSV difference results of the specimens before and after polishing.

[0079]

[0080] As shown in Table 6, despite the uncertainty introduced by the pendulum friction coefficient measuring device during multiple tests using epidote andesite according to the relevant regulations of JJG (Jiaotong) 054-2009, the PSV difference between the specimens before and after the multiple polishing tests remained within a range of 26 to 29. Therefore, to eliminate the impact of the uncertainty introduced by the use of the calibration equipment on the calibration results during the accelerated polishing machine calibration process, the improved method of this application uses the PSV difference between the standard samples before and after the polishing test to determine whether the accelerated polishing machine's overall performance is qualified. According to the results shown in Table 6, the PSV difference between the new standard samples before and after the polishing test ranged from 7 to 13, which meets the calibration standards for the overall accuracy of the accelerated polishing machine specified in the regulations. Therefore, the overall accuracy of the three accelerated polishing machines can be determined to be qualified.

[0081] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made thereto. Therefore, such modifications and improvements, without departing from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

[0082] The terms "upper", "lower", "left", "right", "middle", etc. used in this specification are only for the convenience of description and are not intended to limit the scope of the present invention. Changes or adjustments to their relative relationships should be regarded as within the scope of the present invention without substantially changing the technical content.

Claims

1. A method for calibrating the performance of an accelerated polishing machine, characterized in that: The following steps are involved: Step S100: Select two standard samples that have not been subjected to the polishing test and have been measured, and install the standard samples at road wheel positions 1 and 8 respectively, with the side of the standard sample with the mark facing outward, and install test pieces or simulated test pieces at other positions; Step S200: Install the rubber wheel marked C on the adjustment arm and load No. 30 brown corundum into the sand storage hopper; Step S300, adjusting various parameters of the accelerated polishing machine to meet the requirements; Step S400: Set the number of revolutions to n1 on the control panel, and press the power switch to start the accelerated grinder. Step S500: When the number of revolutions reaches n1, the acceleration grinder automatically stops, the road wheel and the test piece are cleaned, and all residual brown corundum is removed; Step S600: Remove the rubber wheel marked with C and replace it with the rubber wheel marked with X, and load No. 280 green silicon carbide into the sand storage hopper; Step S700: Set the number of revolutions to n2 on the control panel, and press the power switch to start the accelerated grinder. Step S800: When the number of revolutions reaches n2, the acceleration grinder automatically stops, the standard sample is taken out, the road wheel and the test piece are cleaned, and all residual green silicon carbide is removed; Step S900: Measure the polishing values ​​of two standard samples after polishing by the accelerated polishing machine. The formula for calculating the difference between the polishing values ​​of the standard samples before and after polishing in step S900 is: Δ = PSV 0i -PSV 1i ; Where: Δ is the difference between the polishing values ​​of the standard sample before and after polishing; PSV 1i is the polishing value of the standard sample after polishing; PSV 0i The polishing value before the polishing value of the standard sample; Among them, the polishing value of the polished standard sample is compared with the PSV value before polishing to eliminate the introduction of polishing value measurement uncertainty caused by the wear of the rubber sheet of the high-precision pendulum friction coefficient measuring device during the same test process.

2. The method for calibrating the performance of an accelerated polishing machine according to claim 1, characterized in that: Before step S100 , the method also includes: controlling the room temperature to be 20° C.±2° C. 2 hours before the calibration and during the calibration process.

3. The method for calibrating the performance of an accelerated polishing machine according to claim 1, characterized in that: In step S400 and step S500 , n1=3200.

4. The method for calibrating the performance of an accelerated polishing machine according to claim 3, characterized in that: Step S400 also includes simultaneously starting the coarse sand speed control button and the water flow meter.

5. The method for calibrating the performance of an accelerated polishing machine according to claim 4, characterized in that: In step S700 and step S800 , n2=6400.

6. The method for calibrating the performance of an accelerated polishing machine according to claim 5, characterized in that: Step S700 also includes simultaneously starting the fine sand speed regulating button and the water flow meter.

7. The method for calibrating the performance of an accelerated polishing machine according to claim 1, characterized in that: The difference in PSV between the standard samples before and after the polishing test should be 7 to 13, which means that the performance test of the accelerated polishing machine has passed.

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