Description of the principle and test procedure of the flame retardant tester for melt blown filter media
Shanghai Chengwei Instrument Technology Co., Ltd. is suitable for the determination of the flame retardant properties of medical melt blown filter materials and all protective melt is blown filter materials. It can be used by the medical inspection department, safety inspection department, and scientific research unit.
1.1 Test principle
1. Use a standard energy heat source to test the melt-blown filter material to observe the combustion behavior of the melt-blown filter material. The energy of the fire source is guaranteed by measuring the height and temperature of the flame.
2. The time for melt-blown filter material or other samples to pass through the fire source is stipulated by the standard, and the action time of the fire source is ensured by controlling the moving speed of the mask.
3. The burning behavior of the sample is measured by the flame burning and flameless burning of the sample.
a. Plug in the power socket on the back cover of the instrument to turn on the power, connect the air inlet to the propane cylinder, and open the gas cylinder valve to switch on the gas source.
b. Close the front door of the combustion test chamber, and place the "power" switch in the "on" position, and the power indicator light is on.
c. First make the nose tip of the metal head die downward, bring the melt blown filter material to the metal head die, and slightly force the head die with your hands. When the nose tip of the head die is just above the igniter, adjust the igniter head The height (turn the igniter head clockwise to lower, and turn the igniter head counterclockwise to raise) so that the distance between the tip of the igniter and the tip of the nose of the head die is 20±2mm.
d. Press the "Igniter Return" button to restore the burner to the ignition position.
e. Press the "head mold return" button to return the head mold to the starting position. Press the "Zero" key, and the instrument will return to the initial state.
f. Keep pressing the "ignition" button, adjust the propane medium pressure valve "pressure adjustment" knob (according to the end of the knob indicating the "+" direction to increase, "-" direction to decrease to adjust), so that the top pressure of the instrument box The pointer of the meter points at 20kPa.
g. At this time, the ignition resistance wire has turned red. After lighting the igniter, release the "ignition" button. When it is difficult to ignite, please adjust the "flame adjustment" button, the clockwise direction is to reduce the flow of combustible gas, and the counterclockwise direction is to increase the flow of combustible gas. If the ignition is not successful for some reason, in order to prevent the gas from continuing to pass in and cause an explosion, click "continuous combustion stop" to stop the gas, and then click "clear" to restore the initial state.
h. Open the front door of the combustion test chamber, place the flame height gauge (height 40mm) directly in front of the flame by hand, turn the "flame adjustment" knob to adjust the flame height to 40mm±2mm, after the flame stabilizes, remove the flame height gauge, At this time, observe whether the "temperature display" on the panel of the instrument is stable at 800±50℃. If it is not enough, it can be adjusted by increasing the inlet pressure of the gas cylinder pressure reducing valve to stabilize the flame temperature at 800±50℃.
i. Press the "ignitor start" button to move the igniter to the ignition position, press the "headform start" button, the head mold starts to rotate after the head mold is turned in place, the igniter stops gas and resets, "continue burning time" "Automatic timing; after the continuous burning, press the "continuous burning stop" button; if there is no continuous burning, directly press the "continuous burning stop" button, after the smoldering ends, press the "smoldering stop" button again, and record the continuous burning time And smoldering time.
j. Press the "head mold return" button to restore the head mold to the starting position, open the front door of the combustion test box to remove the sample, and the test is over.
k. Press the "Clear" button, the instrument will return to the initial state, and the next melt blown filter material sample will be carried on the metal head mold. At this time, the next test can be carried out according to steps 6-11. If you don't need the next test, please turn off the power, unplug the power plug, take out the residue container, and clean up the burning residue.
l. If you want to test the flame retardancy of the melt blown filter material belt, you must put the melt blown filter material on the metal head mold, loosen the "head mold positioning screw", and rotate the head mold to make the melt blown filter material tape down. Press the "head mold start" button, the head mold starts to rotate, when the head mold is just above the igniter, press the "smolder stop" button to stop the head mold, adjust the height of the igniter head to make the top of the igniter The distance from the zuidi of the head mold is 20±2mm;
m. Follow steps 6-11 to test. When testing materials, use injection molding, compression molding, or compression molding to make the required shape. If the above method is not feasible, a sample should be cut from a representative sample of the material. After the production is completed, use fine sandpaper to grind each cut surface of the incision smoothly, and carefully remove all dust and particles on the surface. The sample size should be at least 60mm in length and 60mm in width (inside the fixture). The thickness values include: 0.1mm±0.02mm, 0.2mm±0.02mm, 0.4mm±0.05mm, 0.75mm±0.10mm, 1.5mm±0.15mm, 3.0mm±0.2mm or 6.0mm±0.4mm.
When testing the finished product, if possible, the sample should be a complete product; if the test cannot be performed on the complete product, you can:
a) Cut a piece of parts to be inspected;
b) Make a small hole in the complete product to make it contact with the glow wire;
c) Take out the parts that need to be inspected from the complete finished product and conduct individual tests.