Overview
QFR type solvent resistance tester is designed and manufactured according to GB/T 17748-1999 standard, which is used to measure the solvent resistance performance of similar substrate coatings such as aluminum-plastic composite plates. The instrument has reasonable structure, reliable performance, simple operation and automatic counting function.
Features
1. Designed according to the national standard GB/T17748-1999, the testing standards are unified.
2. Reasonable structure and reliable performance.
3. Simple operation, Degree of automation, with automatic counting function.
Principle
The instrument uses a flexible wipe head that parcels four layers of medical gauze, absorbs a specific solvent, and scrubs back and forth at the same position on the coating surface at a specified pressure and Frequency until a preset number of times is reached. Then the solvent resistance of the coating is evaluated by visually detecting whether the inner layer (exposed bottom) appears at the scruf.
Applications
Determination of coating solvent resistance of aluminum-plastic composite plate, Miscellaneous substrate coating solvent resistance
Steps
1. Remove the brush arm, remove the lock mother and the pressing ring, wipe the head with four layers of medical gauze parcel about 15mm in size, and fix it with the pressing ring and the locking ring.
2. Put the prepared sample into the sample box and clamp it to ensure that it is not strung during work.
3. Put the brush arm back into the instrument and fasten it with a butterfly nut to ensure that the wipe head part can move up and down freely, and its weight falls completely on the sample.
4. Unscrew the knurled nut on the upper part of the wipe head, pour in the test solvent (such as butanone or Xylene), and adjust the knob to make the gauze full and keep it soaked.
5. Turn on the power supply, turn on the switch, set the number of scruf times according to the standard, press the active setting switch to display the set value, and then press the start switch to start working.
6. The instrument automatically stops after counting to the set value, and can be stopped by pressing the pause switch halfway through.
7. Press the reset switch, remove the brush arm and wipe head parts, take out the sample, visually check whether there is an inner layer phenomenon at the scruf, and take the worst result among the three samples as the final test result.
Notice
• Preparative samples shall comply with the provisions of Article 63.1 of the GB17748-1999 standard.
• The sample must be clamped after being placed in the sample box to ensure that no string movement occurs during the test.
• After installing the brush arm, ensure that the wiper member can move up and down freely in the arm, and its own weight is fully applied to the sample.
• The appropriate solvent specified in the standard should be selected according to the test material (such as exterior/interior-wall aluminum-plastic panels or Miscellaneous substrates).
• After turning on the power supply, if the count shows a value, press the reset switch to clear it first.
• The test results are determined by the worst performance among the three samples.
