A method and apparatus for testing the flexibility of a coating

Abstract

The application discloses a coating flexibility test method and a test device. The method is characterized by coating a test plate with a coating to be tested, placing the test plate into the test device, setting the motor rotating speed, the test time and the bending amplitude, and then testing the flexibility grade of the coating. The method can simulate the deformation of the substrate through the periodic reciprocating movement of the substrate, and can evaluate the deformation capacity of the coating together with the substrate.

Description

Technical Field

[0001] This invention relates to the field of coating testing in marine oil engineering, and particularly to a method and apparatus for testing coating flexibility. Background Technology

[0002] Coating flexibility is one of the important indicators for evaluating coating performance. Currently, industry and national standards mainly test coating flexibility by bending a coating test plate around a conical or cylindrical axis, or bending it on shafts of different diameters. The flexibility of the coating is expressed as the minimum shaft diameter (mm) that does not cause damage to the paint film. However, in the petrochemical industry, coatings rarely fail due to the movement of a single substrate. In some oil and gas processing equipment, thermal expansion and contraction, venting, and filling are repeated continuously. Under external forces, the coating continuously stretches and contracts. Coatings with poor flexibility will crack and peel off. Therefore, higher requirements are placed on coatings that can undergo repeated deformation along with the substrate without damage. Coating flexibility generally refers to the ability of the coating to deform along with the substrate without damage when the substrate is bent by external forces. Traditional testing methods mainly use bending coating test plates to determine the maximum shaft diameter at which the coating cracks and / or peels off from the substrate to assess the coating's flexibility. However, this method cannot complete the test of the flexibility of coatings subjected to periodic bending deformation. Summary of the Invention

[0003] The present invention discloses a coating flexibility testing method and testing device, which can perform a periodic bending deformation flexibility test on the coating of the test plate.

[0004] To address the aforementioned technical problems, this invention provides a method for testing the flexibility of a coating, which is accomplished through the following steps:

[0005] S1. Set the size and specifications of the test plate, treat the surface of the test plate, and then apply the test coating to the surface of the test plate.

[0006] S2. After the coating has reached the specified drying and curing time, use a coating leak tester to inspect the surface of the test panel to ensure that the coating is free of defects such as pinholes.

[0007] S3. The distance between the sliding bracket and the L-shaped bracket on the testing device is specified as 1-5 levels, from small to large, and the test starts from level 5.

[0008] S4. Install the test plate onto the fixture assembly of the test device;

[0009] S5. Set the motor speed, test time and vertical deviation of the test plate, start the motor and begin reciprocating bending of the test plate;

[0010] S6. After the test time is reached, turn off the motor and remove the test plate;

[0011] S7. Under sufficient light conditions, observe whether the coating has a network pattern, cracks and peeling. If necessary, a 10x magnifying glass can be used for observation. If the test panel has the above defects, it indicates that the flexibility test has failed.

[0012] S8. Use a coating leak tester to measure for minor damage to the surface. If an alarm is triggered, the flexibility test fails.

[0013] S9. Once the flexibility test for this level is passed, continue to shorten the support spacing to the previous level and continue testing. Repeat steps S4-S8 until the coating is damaged or the highest level 1 is reached and the test is stopped.

[0014] S10. The minimum spacing at which the coating does not become damaged corresponds to the flexibility level. Record the data to complete the coating flexibility test.

[0015] A coating flexibility testing device includes a support assembly, a crankshaft connecting rod assembly, and a fixing assembly;

[0016] A support assembly, comprising a base and an L-shaped bracket and a sliding bracket fixed to the base, wherein two L-shaped brackets and two sliding brackets are provided, respectively located on both sides of the base;

[0017] A crankshaft and connecting rod assembly, the crankshaft and connecting rod assembly including a crankshaft and a connecting rod, one end of the crankshaft being fixed to the output shaft of a motor, and the other end being hinged to one end of the connecting rod;

[0018] A fastener assembly, comprising a rotating shaft, a horizontal tube, two support plates, and a limiting post, wherein the two ends of the rotating shaft and the horizontal tube are respectively fixed to the two support plates, and wherein the limiting post is disposed on the horizontal tube, and the lower end of the limiting post passes through the horizontal tube;

[0019] The retainer assembly comprises three parts, which are respectively installed on the crankshaft connecting rod assembly, the sliding bracket, and the L-shaped bracket. The other end of the connecting rod and the top end of the L-shaped bracket are respectively hinged to the rotation axis of the retainer assembly, and the top end of the sliding bracket is slidably connected to the rotation axis of the retainer assembly.

[0020] Furthermore, the top of the sliding bracket is provided with a sliding part, the sliding part is provided with a slide rail, the rotating shaft is located in the slide rail and slides with the slide rail.

[0021] Furthermore, the top of the L-shaped bracket is provided with a through hole, through which the rotating shaft passes, and the two support plates are located on the outside of the two L-shaped brackets.

[0022] Furthermore, the motor is fixed to the base.

[0023] Furthermore, both the L-shaped bracket and the sliding bracket include a horizontal plate and a vertical plate fixed at one end. The horizontal plate is fixed to the base, and the sliding part is located at the top of the vertical plate on the sliding bracket.

[0024] Furthermore, the base is rectangular, and multiple positioning holes are provided on both sides of the base. Adjusting bolts are inserted into the positioning holes through the horizontal plate to fix the horizontal plate to both sides of the base. The distance between the L-shaped bracket and the sliding bracket can be adjusted by inserting the adjusting bolts into different positioning holes.

[0025] The technical effect of the present invention is that it provides a coating flexibility testing method, which simulates deformation by the periodic reciprocating motion of the substrate and evaluates the coating's ability to undergo periodic deformation along with the substrate.

[0026] The present invention also provides a coating flexibility testing device, including a support assembly, a crankshaft connecting rod assembly, and a retainer assembly. The retainer assembly is installed on the support assembly and the crankshaft connecting rod assembly respectively. The test plate coated with the coating is installed on the retainer assembly. The motor drives the crankshaft connecting rod assembly to move, and then drives the middle retainer assembly to move up and down, thereby enabling the test plate to bend periodically, thereby completing the coating flexibility test. Attached Figure Description

[0027] Figure 1 This is a three-dimensional schematic diagram of a coating flexibility testing device provided by the present invention.

[0028] Figure 2 A perspective view of the fixture assembly in a coating flexibility testing device provided by the present invention.

[0029] Reference numerals: 1. Adjusting bolt; 2. Positioning hole; 3. Base; 4. Sliding bracket; 5. Test plate; 6. Connecting rod; 7. Motor; 8. Fixing assembly; 9. L-shaped bracket; 81. Rotating shaft; 82. Limiting post; 83. Horizontal tube; 84. Support plate. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0031] This invention provides a method for testing the flexibility of a coating, combined with the attached... Figure 1-2 As shown, this can be completed through the following steps:

[0032] S1. Set the size and specifications of the test plate 5, treat the surface of the test plate 5, and then apply the test coating to the surface of the test plate 5.

[0033] S2. After the coating has reached the specified drying and curing time, use a coating leak tester to inspect the surface of test plate 5 to ensure that the coating is free of defects such as pinholes.

[0034] S3. The distance between the sliding bracket and the L-shaped bracket 9 on the testing device is specified as 1-5 levels, from small to large, and the test starts from level 5.

[0035] S4. Install the test plate 5 onto the fixture assembly 8 of the test device;

[0036] S5. Set the speed of motor 7, test time and vertical deviation of test plate 5, start motor 7 and begin to bend test plate 5 back and forth.

[0037] S6. After the test time is reached, turn off the motor 7 and remove the test plate 5;

[0038] S7. Under sufficient light conditions, observe whether the coating has a network pattern, cracks and peeling. If necessary, a 10x magnifying glass can be used for observation. If test plate 5 has the above defects, it indicates that the flexibility test has failed.

[0039] S8. Use a coating leak tester to measure for minor damage to the surface. If an alarm is triggered, the flexibility test fails.

[0040] S9. Once the flexibility test for this level is passed, continue to shorten the support spacing to the previous level and continue testing. Repeat steps S4-S8 until the coating is damaged or the highest level 1 is reached and the test is stopped.

[0041] S10. The minimum spacing at which the coating does not become damaged corresponds to the flexibility level. Record the data to complete the coating flexibility test.

[0042] In this embodiment, the specific steps are as follows:

[0043] (1) The test plate 5 is a rectangular test plate 5 with a thickness of 2mm and a length of 900mm. The test plate 5 should be flat, without deformation, and without any visible bulges or cracks on the surface. The test plate 5 should be subjected to the specified surface treatment, with a treatment level of Sa3.0, and the coating product to be tested should be applied.

[0044] (2) After the coating has reached the specified drying and curing time, use a leak tester to inspect the surface to ensure that there are no defects such as pinholes in the coating. For coatings ≤500μm, use a low-pressure wet sponge leak tester; for coatings >500μm, use a high-voltage electric spark leak tester.

[0045] (3) The distance between the sliding bracket and the L-shaped bracket 9 is adjustable, and is divided into 1-5 levels. The corresponding spacing is shown in Table 1. Adjust the L-shaped bracket 9 and the sliding bracket to the maximum spacing of 711.2mm (level 5), and tighten the adjusting bolt 1 to fix the bracket.

[0046] Table 1 Correspondence between Grade and Spacing

[0047] Flexibility level Level 1 Level 2 Level 3 Level 4 Level 5 Spacing (mm) 304.8 406.4 508 609.6 711.2

[0048] (4) Install the test plate 5 on the test plate 5 fixture assembly 8.

[0049] (5) Set the speed of motor 7 to 50 r / min, fix the vertical deviation of the middle position of test plate 5 to ±50 mm, and the number of reciprocating cycles to 5000. Calculate the running time of motor 7 based on the speed of motor 7, turn on motor 7, and start the test.

[0050] (6) When the time is reached, stop the motor 7. After the cycle is completed, turn off the motor 7 and disassemble the test plate 5.

[0051] (7) Under sufficient light conditions, observe whether the coating has a network pattern, cracks and peeling. If necessary, a 10x magnifying glass can be used for observation. If the test plate 5 has the above defects, it indicates that the flexibility test has failed.

[0052] (8) Use a coating leak tester to measure whether there is any minor damage on the surface. If an alarm is triggered, the flexibility test will fail.

[0053] (9) When the flexibility test of this level is passed, the support spacing is shortened to the previous level and the test is carried out again. The test is repeated on the test plate 5 until the coating is damaged or the highest level 1 is reached and the test is stopped.

[0054] (10) The minimum spacing at which the coating does not become damaged corresponds to the flexibility level. Record the data to complete the coating flexibility test.

[0055] This invention also discloses a coating flexibility testing device, combined with Figure 1-2 As shown, a coating flexibility testing device includes a support assembly, a crankshaft connecting rod assembly, and a fixing assembly.

[0056] The support assembly includes a base 3 and an L-shaped bracket 9 and a sliding bracket fixed to the base 3. Two L-shaped brackets 9 and two sliding brackets are provided, respectively located on both sides of the base 3. Both the L-shaped bracket 9 and the sliding bracket include a horizontal piece and a vertical piece fixed at one end, and the horizontal piece of both is fixed to the base 3.

[0057] The base 3 is rectangular, and multiple positioning holes 2 are provided on both sides of the base 3. The adjusting bolt 1 passes through the horizontal plate and is inserted into the positioning hole 2. The positioning hole 2 has a thread, which cooperates with the adjusting bolt. Tightening the adjusting bolt 1 can fix the horizontal plate to both sides of the base 3. The distance between the L-shaped bracket 9 and the sliding bracket can be adjusted by inserting the adjusting bolt 1 into different positioning holes 2.

[0058] The crankshaft and connecting rod assembly includes a crankshaft and a connecting rod 6. One end of the crankshaft is fixed to the output shaft of the motor 7, and the other end is hinged to one end of the connecting rod 6. The motor 7 is fixed to the base 3. The crankshaft and connecting rod assembly can convert the rotational motion of the motor 7 into the linear reciprocating motion of the connecting rod 6.

[0059] The fixture assembly 8 includes a rotating shaft 81, a horizontal tube 83, two support plates 84, and a limiting post 82. The two ends of the rotating shaft 81 and the horizontal tube 83 are respectively fixed to the two support plates 84. The limiting post 82 is located on the horizontal tube 83, and its lower end passes through the horizontal tube 83. The limiting post 82 is threadedly connected to the horizontal tube 83. During testing, the limiting post 82 is rotated so that its lower end abuts against the test plate 5, thereby pressing the test plate 5 tightly against the rotating shaft 81.

[0060] There are three retainer assemblies 8, which are respectively installed on the crankshaft connecting rod assembly, the sliding bracket and the L-shaped bracket 9. The other end of the connecting rod 6 and the top of the L-shaped bracket 9 are respectively hinged to the rotation shaft 81 of the retainer assembly 8, and the top of the sliding bracket is slidably connected to the rotation shaft 81 of the retainer assembly 8.

[0061] The sliding bracket has a sliding part at its top, which is located at the top of the vertical plate on the sliding bracket. The sliding part has a slide rail, and the rotating shaft 81 is located in the slide rail and slides in contact with the slide rail. During the test, the rotating shaft 81 installed in the slide rail can slide within the slide rail to compensate for the deformation caused by the up-and-down movement of the test plate 5.

[0062] The top of the L-shaped bracket 9 has a through hole through which the rotating shaft 81 passes, and the two support plates 84 are located on the outside of the two L-shaped brackets 9. During the test, the retainer assembly 8 on the L-shaped bracket 9 can swing around the rotating shaft 81.

[0063] Motor 7 drives the crankshaft connecting rod assembly to move, causing connecting rod 6 to reciprocate up and down. The upper end of connecting rod 6 is hinged to the middle retainer assembly 8, which drives the middle retainer to move up and down, thereby enabling test plate 5 to reciprocate bending motion to test the flexibility of the coating on test plate 5.

[0064] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A method for testing the flexibility of a coating, comprising the following steps, characterized in that: S1. Set the size and specifications of the test plate, treat the surface of the test plate, and then apply the test coating to the surface of the test plate. S2. After the coating has reached the specified drying and curing time, use a coating leak tester to inspect the surface of the test panel to ensure that the coating has no pinhole defects. S3. The distance between the sliding bracket and the L-shaped bracket on the testing device is specified as 1-5 levels, from small to large, with testing starting from level 5; the testing device includes a bracket assembly, a crankshaft connecting rod assembly, and a fixing assembly. The support assembly includes a base and an L-shaped bracket and a sliding bracket fixed to the base. There are two L-shaped brackets and two sliding brackets, which are respectively located on both sides of the base. The crankshaft and connecting rod assembly includes a crankshaft and a connecting rod. One end of the crankshaft is fixed to the output shaft of the motor, and the other end is hinged to one end of the connecting rod. The fixing assembly includes a rotating shaft, a horizontal tube, two support plates and a limiting post. The two ends of the rotating shaft and the horizontal tube are respectively fixed to the two support plates. The limiting post is located on the horizontal tube and the lower end of the limiting post passes through the horizontal tube. The fixed assembly has three parts, which are respectively installed on the crankshaft connecting rod assembly, the sliding bracket and the L-shaped bracket. The other end of the connecting rod and the top end of the L-shaped bracket are respectively hinged to the rotation axis of the fixed assembly, and the top end of the sliding bracket is slidably connected to the rotation axis of the fixed assembly. S4. Install the test plate onto the fixing component of the test device; S5. Set the motor speed, test time and vertical deviation of the test plate, start the motor and begin reciprocating bending of the test plate; S6. After the test time is reached, turn off the motor and remove the test plate; S7. Under sufficient light conditions, observe whether the coating has a network pattern, cracks and peeling. Use a 10x magnifying glass for observation. If the test panel has the above defects, it indicates that the flexibility test has failed. S8. Use a coating leak tester to measure for minor damage to the surface. If an alarm is triggered, the flexibility test fails. S9. Once the flexibility test for this level is passed, continue to shorten the support spacing to the previous level and continue testing. Repeat steps S4-S8 until the coating is damaged or the highest level 1 is reached and the test is stopped. S10. The minimum spacing at which the coating does not become damaged corresponds to the flexibility level. Record the data to complete the coating flexibility test.

2. The coating flexibility testing method according to claim 1, characterized in that: The top of the sliding bracket is provided with a sliding part, and the sliding part is provided with a slide rail. The rotating shaft is located in the slide rail and slides with the slide rail.

3. The coating flexibility testing method according to claim 1, characterized in that: The top of the L-shaped bracket is provided with a through hole, through which the rotating shaft passes, and the two support plates are located on the outside of the two L-shaped brackets.

4. The coating flexibility testing method according to claim 1, characterized in that: The motor is fixed to the base.

5. The coating flexibility testing method according to claim 2, characterized in that: Both the L-shaped bracket and the sliding bracket include a horizontal plate and a vertical plate fixed at one end. The horizontal plate is fixed to the base, and the sliding part is located at the top of the vertical plate on the sliding bracket.

6. The coating flexibility testing method according to claim 5, characterized in that: The base is rectangular, and multiple positioning holes are provided on both sides of the base. Adjusting bolts are inserted into the positioning holes through the horizontal plate to fix the horizontal plate to both sides of the base. The distance between the L-shaped bracket and the sliding bracket can be adjusted by inserting the adjusting bolts into different positioning holes.

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