The building material flammability tester is a test method to determine whether building materials are flammable under specified conditions. It is developed according to the technical parameters stipulated in the national standard GB8626. The test furnace uses a small flame to directly impact a vertically placed sample in a normal combustion environment to determine the flammability of building products. The building material flammability tester uses the Kleinbrenner (Kleinbrenner) principle to measure the combustion performance of B-class building materials under the direct impact of a small flame in the vertical direction.
The building material flammability tester is suitable for judging whether building materials and their products have flammability test methods under specified conditions. It is mainly used for the evaluation of flame retardant grade B1 and B2 of extruded board, molded board, polystyrene board, polyurethane, phenolic board and other insulation materials. The flammability tester for building materials is exquisite in shape, resistant to flue gas corrosion, the control part and the test part are controlled separately, and the degree of automation is high. The key components are imported parts, and the digital display time, flame temperature and test program are automatically controlled. It is easy to use, stable and reliable. .
Test operation steps
1. Sample preparation:
The shape and size of the sample: the standard sample size is 250mm+0/-1mm, and the width is 90mm+0/-1mm.
2. Sampling: Samples whose nominal thickness does not exceed 60mm should be tested according to their actual thickness. For samples with a nominal thickness greater than 60mm, the thickness shall be reduced to 60mm from the unexposed surface, and the test shall be carried out according to the thickness of 60mm. If it is necessary to reduce the size of the specimen in this way, the cut surface shall not be used as the fire receiving surface. For articles that are normally produced to a size smaller than the specimen size, appropriately sized specimens shall be prepared exclusively for testing. The sampling method and quantity are as follows:
a) For each ignition mode, at least 6 representative product samples should be tested, and 3 samples should be cut in the longitudinal direction and transverse direction of the sample respectively.
b) If the thickness of the product used for the test is asymmetrical, and both surfaces may be exposed to fire in practical applications, the two surfaces of the sample should be tested separately.
c) If several surface areas of an article differ significantly, but each conforms to the surface characteristics specified below, an additional set of tests shall be used to evaluate the article.
The product should have one of the following characteristics:
i. Level the fire-receiving surface;
ii. If the surface of the product is irregular, but the entire fire-receiving surface uniformly reflects such irregularities, it can be regarded as a flat fire-receiving surface as long as the following requirements are met:
1) On the surface of the representative area of 250mmX250mm, the vertical distance between at least 50% of the surface and the plane where the high point of the fire receiving surface is located shall not exceed 6mm;
2) For surfaces with gaps, cracks or holes, the width of the gaps, cracks or holes should not exceed 6.5mm, and the depth should not exceed 10mm, and the surface area should not exceed 30% of the 250mmX250mm representative area of the fire receiving surface.
d) If the article is edge-sealed on all sides during installation, but can still be used without edge protection, the edge-sealed and unsealed specimens shall be tested separately.
3. Substrate
If the article is mounted on a substrate under end-use conditions, the test specimen shall be representative of the end-use conditions. And the base material should be selected according to EN13238.
4. State regulation
Test specimens and filter papers shall be conditioned according to EN 13238.
5. Test preparation
a) Under the conditions of only igniting the burner and opening the exhaust hood, control the air velocity in the flue of the box to (0.7±0.1) m/s;
b) Take 6 samples out of the state adjustment chamber and complete the test within 30 minutes. If necessary, the sample can also be taken out from the state adjustment room and placed in the test device in the airtight box;
c) Place the sample in the sample holder, so that the two edges and the upper edge of the sample are closed by the sample holder, and the fire end is 30mm away from the bottom end of the sample holder
d) Press the start test button on the panel, the burner will automatically move to the right, then turn off the power of the equipment, adjust the angle of the burner to 45°, use the positioner for edge ignition and surface ignition, and adjust the position on the hanging rod 16 The positioning circle of the center aligns the left and right positions. If the up and down positions need to be adjusted, press the stop button 5 and turn on the power, and twist the up/down switch 13 to confirm the distance between the burner and the sample.
e) Put two pieces of filter paper in the aluminum foil collection tray under the sample, this operation should be completed within 3 minutes before the test.
6. Test steps
1) After connecting the gas source, open the gas source valve, press the ignition button on the panel, the device will automatically ignite and ignite the burner in the vertical direction, and wait for the flame to stabilize.
2) Adjust the flame adjustment 14, and measure the flame height with a flame gauge, the flame height should be (20±1) mm. In order to ensure the accuracy of the test, the flame height should be measured before each ignition of the sample.
3) Adjust the angle of the burner to 45°, press the start test button, the burner will automatically ignite and start to move to the right, when it reaches the position set in the test preparation, the equipment will automatically start the flame application time.
4) When the timing reaches the flame application time, the burner will automatically turn off and return, and at this time, the flame holding time timing will be automatically started.
5) When the afterflame of the sample is extinguished or the high point of the afterflame reaches the designated marking line, press the pause button, and the flame holding time will stop counting.
6) Press the reset button on the control panel, all test data will be cleared, and the next sample test can be prepared.