Water erosion resistance testing method and application

Abstract

The invention relates to the technical field of water-washing-resistant testing, in particular to a water-washing-resistant testing method and application thereof.The water-washing-resistant testing method at least comprises the following steps that 1, a water-washing-resistant testing device is adopted, a filling mold of a filler groove is filled with a sample to be tested, and the sample to be tested is fixed to a slot support; (2) a water pump is started to control water flow pressure, a water supply valve is opened, circulating water in a water storage tank is conveyed through a water conveying pipe, a flowmeter monitors the water flow in the water conveying pipe, and water flow in the water conveying pipe conducts a water-scouring-resistant experiment on the to-be-tested sample in the filling mold through a nozzle; (3) after the water scouring resistance experiment is finished, closing the water pump, stopping water flow conveying, taking out the filler tank, measuring the trace depth of the to-be-tested sample scoured by the water flow in the filling mold, performing parallel test for at least two times, and taking an average value as a test result; the water flow rate in the water conveying pipe is 2.3-2.5 L / min; the water flow pressure is 0.1 MPa, and the water washing resistance of the sealing grease can be accurately and scientifically evaluated.

Description

Technical Field

[0001] The invention relates to the technical field of water scour resistance testing, and in particular to a water scour resistance testing method and application. Background Art

[0002] The shield tail sealing system plays a vital role in preventing shield tail leakage and ensuring the smooth construction of shield tunneling projects. In particular, the working performance of the shield tail grease is closely related to the sealing performance of the shield tail system. The shield tail sealing grease will encounter water in the process of working and use, and it is easy to be washed away by water, resulting in a large loss of shield grease. In the long run, it will cause damage to the equipment structure. Therefore, the shield tail sealing grease must have good flushing performance. At present, there are many domestic and foreign sealing grease manufacturers, and the quality of grease is also uneven. However, the evaluation method for the water flushing resistance of the shield tail sealing grease is not perfect, and it is impossible to accurately and scientifically evaluate the water flushing resistance of the sealing grease. For example, the Chinese utility model (authorization announcement number is CN216665612U) discloses a test device for the water flushing resistance of the shield tail grease. The distance between the top of the filler mold and the fan-shaped nozzle in the device is a fixed value, which cannot simulate the impact of water flow under different working conditions. The Chinese utility model (authorization announcement number CN220289364U) discloses a test device for testing the water erosion resistance of shield tail sealing grease. The device can be directly connected to a water source to obtain continuous test water for uninterrupted testing. At the same time, it can simulate water flow impact conditions under different working conditions in a shorter test time and at a lower cost and obtain reliable test data. However, the device is complex, the operation process is cumbersome, and there are many process steps. From the perspective of cost and working hours, it does not meet the testing requirements of engineering projects. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a water scour resistance test method, which is simple and easy to operate, can accurately and scientifically evaluate the water scour resistance performance of sealing grease, and meets the testing requirements of engineering projects from the perspective of cost and working hours.

[0004] In one aspect, the present invention provides a method for testing water scour resistance, which comprises at least the following steps: (1) Using a water scour resistance test device, fill the sample to be tested into the filling mold of the filling slot and fix the filling slot to the slot bracket; (2) Start the water pump to control the water flow pressure, open the water supply valve, and transport the circulating water in the water tank through the water pipe. The flow meter monitors the water flow in the water pipe. The water in the water pipe passes through the nozzle to perform a water scour resistance test on the sample to be tested in the filling mold; (3) After the water scouring test is completed, turn off the water pump, stop the water flow, remove the filling tank, measure the depth of the traces of the sample to be tested in the filling mold scouring by the water flow, and obtain the test results.

[0005] As a preferred technical solution, the water scour resistance test device at least includes: a water storage tank, a test box, a filter baffle, a water pipe, a nozzle, a slot bracket, a filling tank, a test bench, a water pump, and a flow meter. A filter baffle is arranged between the water storage tank and the test box. The circulating water in the water storage tank forms a fan-shaped water flow scouring area through the water pipe and the nozzle at the terminal of the water pipe. The fan-shaped water flow scouring area locks the top center of the filling tank. The filling tank is detachably connected to the slot bracket. The slot bracket is fixed inside the test box. A test bench is arranged at the bottom of the slot bracket. The flow meter is arranged on the water pipe for monitoring the water flow in the water pipe. The water pipe is connected to the water pump.

[0006] As a preferred technical solution, the nozzle is a fan-shaped nozzle, and the equivalent aperture of the fan-shaped nozzle is 2-3 mm, preferably 2.4 mm.

[0007] As a preferred technical solution, the jet angle of the fan-shaped nozzle is 30-120°, preferably 50-90°, and most preferably 50°.

[0008] As a preferred technical solution, the dimensions of the filling mold include: length × width × thickness: (50-200) mm × (20-50) mm × (1-10) mm, preferably (80-120) mm × (30-50) mm × (3-8) mm, and most preferably 100 mm × 40 mm × 5 mm.

[0009] As a preferred technical solution, the water flow pressure is 0.05-0.5 MPa, preferably 0.05-0.1 MPa, and most preferably 0.1 MPa.

[0010] As a preferred technical solution, the water flow rate in the water pipe is 2-3 L / min, preferably 2.3-2.5 L / min.

[0011] As a preferred technical solution, the vertical distance between the bottom of the nozzle and the top of the filling slot is ≥5 cm, preferably 6-10 cm, and most preferably 6±0.5 cm.

[0012] As a preferred technical solution, the sample to be tested is subjected to constant temperature pretreatment before filling, and the specific steps include: placing the sample to be tested in a constant temperature box and controlling the temperature to 15-30°C for at least 3 hours. Preferably, the constant temperature pretreatment is: placing the oil sample to be tested in a constant temperature box and controlling the temperature to 20±3°C for at least 3 hours.

[0013] As a preferred technical solution, the duration of the water scour resistance test is 10-60 minutes, preferably 20-40 minutes, and most preferably 30 minutes.

[0014] As a preferred technical solution, the pore size of the filter partition is ≤2 mm.

[0015] As a preferred technical solution, the statistical standard of the trace depth includes: measuring the depth of the deepest trace of the sample to be tested washed by water.

[0016] Preferably, the test result is an average value of the trace depth after at least two parallel tests.

[0017] The water scour resistance test method provided by the present invention realizes low-cost, rapid and reliable evaluation of the water scour resistance performance of the shield tail sealing grease by adopting a water scour resistance test device and coordinating the control of various test parameter conditions, and can be widely promoted and applied. Specifically, the present invention adopts a fan-shaped nozzle to comprehensively control the equivalent aperture, jet angle and vertical distance between the bottom of the fan-shaped nozzle and the top of the filling groove to ensure the precision, repeatability and reproducibility of the test results. Furthermore, by coordinating the control of water flow pressure and water flow in the water pipe and the duration of the water scour resistance experiment, the obtained test results can be accurately used for the difference in water scour resistance performance of different shield tail greases or the same batch of shield tail greases, so as to be applied to the development guidance of shield tail grease products and the actual usability evaluation, which has a very high market promotion value.

[0018] In addition, the present invention sets a filter baffle between the water storage tank and the test box. The filter baffle filters the water used in the water scour resistance test and stores it in the water storage tank as circulating water. While realizing the recycling of water to save water resources, it avoids clogging of the water pipe and affecting the subsequent water scour test results.

[0019] Another aspect of the present invention provides an application of a water scour resistance test method, which is applied to the evaluation of the water scour resistance performance of shield tail grease.

[0020] Beneficial Effects 1. The present invention provides a water scour resistance test method, which is simple and easy to operate, and can accurately and scientifically evaluate the water scour resistance performance of sealing grease, and can meet the testing requirements of engineering projects from the perspective of cost and working hours.

[0021] 2. The water scour resistance test method provided by the present invention, by adopting a water scour resistance test device and coordinating the control of various test parameter conditions, can achieve low-cost, rapid and reliable evaluation of the water scour resistance performance of the shield tail sealing grease, and can be widely promoted and applied.

[0022] 3. The present invention adopts a fan-shaped nozzle to comprehensively control the equivalent aperture, jet angle and vertical distance between the bottom of the fan-shaped nozzle and the top of the filling slot, thereby ensuring the precision, repeatability and reproducibility of the test results.

[0023] 4. The present invention coordinates the control of water flow pressure, water flow in the water pipe, and the duration of the anti-water scour test, so that the obtained test results can be accurately used for the differences in the anti-water scour performance of different shield tail greases or the same batch of shield tail greases. This is used for guiding the product development of shield tail greases and evaluating their actual usability, and has extremely high market promotion value.

[0024] 5. The present invention sets a filter baffle between the water storage tank and the test box. The filter baffle filters the water used in the water scour resistance test and stores it in the water storage tank as circulating water, thereby realizing the recycling of water to save water resources and avoiding the blockage of the water pipe and the influence on the subsequent water scour test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram of the structure of the water scour resistance testing device provided in Example 1, Figure 1 Middle: water storage tank 1, test box 2, filter baffle 3, water pipe 4, nozzle 5, slot bracket 6, filling tank 7, test bench 8, water pump 9, flow meter 10.

[0026] Figure 2 This is a physical picture of the water scour resistance testing device provided in Example 1.

[0027] Figure 3 This is a physical picture of the filling mold in which the sample to be tested is filled into the filling slot in Example 1. DETAILED DESCRIPTION

[0028] Example 1 Embodiment 1 of the present invention provides a water scour resistance test method, comprising the following steps: (1) Using a water scour resistance test device, fill the sample to be tested into the filling mold of the filling slot 7, and fix the filling slot 7 to the slot bracket 6; (2) Start the water pump 9 to control the water flow pressure, open the water supply valve, and transport the circulating water in the water tank 1 through the water pipe 4. The flow meter 10 monitors the water flow in the water pipe 4. The water in the water pipe 4 passes through the nozzle 5 to perform a water scour resistance test on the sample to be tested in the filling mold; (3) After the water scouring test is completed, turn off the water pump 9 to stop the water flow, take out the filling tank 7, and measure the depth of the trace of the sample to be tested in the filling mold after being scour by the water flow. After two parallel tests, take the average value as the test result.

[0029] See also Figure 1-3The anti-water scour test device includes: a water storage tank 1, a test box 2, a filter baffle 3, a water pipe 4, a nozzle 5, a slot bracket 6, a filling tank 7, a test bench 8, a water pump 9, and a flow meter 10. A filter baffle 3 is arranged between the water storage tank 1 and the test box 2. The circulating water in the water storage tank 1 forms a fan-shaped water flow scouring area through the water pipe 4 and the nozzle 5 at the terminal of the water pipe. The fan-shaped water flow scouring area locks the top center of the filling tank 7. The filling tank 7 is detachably connected to the slot bracket 6. The slot bracket 6 is fixed inside the test box 2. A test bench 8 is arranged at the bottom of the slot bracket 6. The flow meter 10 is arranged on the water pipe 4 for monitoring the water flow in the water pipe 4. The water pipe 4 is connected to the water pump 9. The water flow in the water pipe 4 is controlled by controlling the pressure of the water pump 9.

[0030] The nozzle is a fan-shaped nozzle, and the equivalent aperture of the fan-shaped nozzle is 2.4 mm.

[0031] The jet angle of the fan-shaped nozzle is 50°.

[0032] The dimensions of the filling mold include: length×width×thickness: 100mm×40mm×5mm.

[0033] The water flow pressure is 0.1 MPa.

[0034] The water flow rate in the water delivery pipe is 2.30 L / min.

[0035] The vertical distance between the bottom of the nozzle and the top of the filling tank is 6±0.5 cm.

[0036] The sample to be tested is subjected to constant temperature pretreatment before filling, and the specific steps include: placing the sample to be tested in a constant temperature box and controlling the temperature to be 20±3° C. for 3 hours.

[0037] The duration of the water scour resistance test is 30 minutes, which is determined by a timer.

[0038] The pore size of the filter partition is 2 mm.

[0039] The statistical standard of the trace depth includes: measuring the depth of the deepest trace of the sample to be tested washed by water flow, and measuring the depth of the deepest trace with a ruler.

[0040] The test method provided in Example 1 of the present invention requires at least 500g of shield tail grease sample; the temperature control accuracy of the constant temperature box is 1°C; the accuracy of the timer is 1s; the measuring range of the ruler is greater than 100mm and the accuracy is 0.1mm.

[0041] The test method provided in Example 1 was used to test different batches of Sample 1. The test results are shown in Table 1.

[0042] Table 1

[0043] The test method provided in Example 1 was used to test different batches of Sample 2. The test results are shown in Table 2.

[0044] Table 2

[0045] The test method provided in Example 1 was used to test different batches of sample 3. The test results are shown in Table 3.

[0046] Table 3

[0047] The data in Table 1-3 show that: (1) The differences in repeated test results for the same batch of products are small, proving that the method has good repeatability.

[0048] (2) There are differences in the test results of different batches of the same product, which proves that there are fluctuations in the product formulas of different batches.

[0049] (3) It is normal for the average depth of the deepest mark of Sample 1 to fluctuate within the range of 16-19 mm. The average depth of the deepest mark of the NT1240100272 batch of products is less than 16 mm. Subsequent analysis may indicate that this is due to process fluctuations resulting in a higher product consistency. The average depth of the deepest mark of the NT1240301530 and NT1240401706 batches of products is greater than 19 mm due to process fluctuations resulting in a lower product consistency.

[0050] (4) It is normal for the average depth of the deepest mark of sample 2 to fluctuate within the range of 22-25 mm. Among them, the average depth of the deepest mark of batches NT1240100317, NT1240100319, NT1240100349, and NT1240100572 is less than 22 mm. Subsequent analysis may have shown that the low consistency of the product was caused by process fluctuations.

[0051] (5) It is normal for the average depth of the deepest mark of Sample 3 to fluctuate within the range of 17-22 mm. The average depth of the deepest mark of the products of batches NT1240603277 and NT1240603457 is less than 17 mm. Subsequent analysis may indicate that this is due to process fluctuations resulting in lower product consistency. The average depth of the deepest mark of the products of batches NT1240603250, NT1240603248 and NT1240603279 is greater than 22 mm, which is due to process fluctuations resulting in higher product consistency.

[0052] (6) Sample 1 has better water erosion resistance than samples 2 and 3, and the water erosion resistance of different batches of products fluctuates less. Subsequent analysis may show that the product formula is better and the process control is more stable. Therefore, this method can be used for the development of shield tail grease formula, production process parameter control and quality evaluation of different batches of products.

[0053] Example 2 Example 2 of the present invention provides a water scour resistance test method, and its specific implementation method is the same as that of Example 1, except that the water flow rate in the water pipe is 2.50 L / min. The test method provided in Example 2 is used to test the NT1240100167 batch number of sample 1, and the test results are shown in Table 4.

[0054] Comparative Example 1 Comparative Example 1 of the present invention provides a water scour resistance test method, and its specific implementation method is the same as Example 1, except that the water flow rate in the water pipe is 2.10L / min. The test method provided in Comparative Example 1 is used to test the NT1240100167 batch number of sample 1, and the test results are shown in Table 4.

[0055] Comparative Example 2 Comparative Example 2 of the present invention provides a water scour resistance test method, and its specific implementation method is the same as Example 1, except that the water flow rate in the water pipe is 2.80L / min. The test method provided in Comparative Example 2 is used to test the NT1240100167 batch number of sample 1, and the test results are shown in Table 4.

[0056] Comparative Example 3 Comparative Example 3 of the present invention provides a water scour resistance test method, and its specific implementation method is the same as that of Example 1, except that the water flow pressure is 0.2 MPa. The test method provided in Comparative Example 3 is used to test the NT1240100167 batch number of sample 1, and the test results are shown in Table 4.

[0057] Comparative Example 4 Comparative Example 4 of the present invention provides a water scour resistance test method, and its specific implementation method is the same as Example 1, except that the water flow pressure is 0.3 MPa. The test method provided in Comparative Example 4 is used to test the NT1240100167 batch number of sample 1, and the test results are shown in Table 4.

[0058] Comparative Example 5 Comparative Example 5 of the present invention provides a water scour resistance test method, and its specific implementation method is the same as Example 1, except that the water flow pressure is 0.5 MPa. The test method provided in Comparative Example 5 is used to test the NT1240100167 batch number of sample 1, and the test results are shown in Table 4.

[0059] Table 4

[0060] From the analysis of Table 4, it can be seen that the changes in the water flow rate and water pressure in the water pipe in Comparative Examples 1-5 lead to deviations in the test results of the products, and the precision of the results of the two parallel tests is reduced.

Claims

1. A water scour resistance test method, characterized in that: At least the following steps are included: (1) Using a water scour resistance test device, fill the sample to be tested into the filling mold of the filling slot and fix the filling slot to the slot bracket; (2) Start the water pump to control the water flow pressure, open the water supply valve, and transport the circulating water in the water tank through the water pipe. The flow meter monitors the water flow in the water pipe. The water in the water pipe passes through the nozzle to perform a water scour resistance test on the sample to be tested in the filling mold; (3) After the water scouring test is completed, turn off the water pump, stop the water flow, remove the filling tank, measure the depth of the trace of the sample to be tested in the filling mold scouring by the water flow, and obtain the test result; The water flow rate in the water delivery pipe is 2.3-2.5 L / min; the water flow pressure is 0.05-0.1 MPa.

2. The water scour resistance test method according to claim 1, characterized in that: The nozzle is a fan-shaped nozzle, and the equivalent aperture of the fan-shaped nozzle is 2-3 mm.

3. The water scour resistance test method according to claim 2, characterized in that: The jet angle of the fan-shaped nozzle is 30-120°.

4. The water scour resistance test method according to claim 3, characterized in that: The jet angle of the fan-shaped nozzle is 50-90°.

5. The water scour resistance test method according to claim 4, characterized in that: The vertical distance between the bottom of the nozzle and the top of the filling tank is ≥5cm.

6. The water scour resistance test method according to claim 5, characterized in that: The duration of the water scour resistance test is 10-60 minutes.

7. The water scour resistance test method according to claim 6, characterized in that: The dimensions of the filling mold include: length×width×thickness: (50-200) mm×(20-50) mm×(1-10) mm.

8. The water scour resistance test method according to claim 7, characterized in that: The sample to be tested is subjected to constant temperature pretreatment before filling, and the specific steps include: placing the sample to be tested in a constant temperature box and controlling the temperature to be 15-30° C. for at least 3 hours.

9. The water scour resistance test method according to claim 8, characterized in that: The statistical standard of the trace depth includes: measuring the depth of the deepest trace of the sample to be tested washed by water flow.

10. An application of the water scour resistance test method according to any one of claims 1 to 9, characterized in that: Applied to the evaluation of the water scouring resistance of shield tail grease.

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