ASTMD 892 foam Tendency Test for gear oil used in wind power generation
In order to prevent foam formation in gear oil, antifoam agent was added to the gear oil. Antifoam agent can change the tension on the surface of bubbles and let the bubbles burst. Qualified quality gear oil will test foam properties before going out. ASTMD 892 foam Tendency Test
Blow the sample at a constant flow rate of 10 'C for 5 min. At the end of each cycle, the volume of foam in the sample was measured. Second samples were taken at 93.5 C for testing. When the foam disappeared, the test was repeated at 24 degrees.
1 without mechanical shaking or stirring, pour about 200 ml. of sample into 600 ml. beaker, heat it to 49 ° C ± 3 ° C and cool it to 24 ° C ± 3 ° C
2 pour the sample into the measuring cylinder to make the liquid level reach the 190 ml mark. Immerse the measuring cylinder in a 24 ℃ bath, immerse it at least to the 900 ml mark, and fix it with a heavy metal ring to prevent floating. When the oil temperature reaches the bath temperature, plug the plug, connect the diffusion head and the air inlet pipe not connected with the air source, soak the diffusion head for about 5 minutes, connect the air outlet pipe with the gas volume measuring device, connect the air source, and adjust the air flow rate to 94 ml / min ± 5 ml / min. SH126 gear oil foam analyzer Shandong Sheng Tai instrument production through the gas diffusion head air requirements are clean and dry. Start timing from the occurrence of a bubble in the gas diffusion head, and ventilate for 5 min ± 3S. Record the volume of the foam immediately, that is, the volume of the liquid minus the total volume, to 5 mL accurately. The total volume of air passing through the system shall be 470 ml ± 25 ml. Remove the hose from the flowmeter and cut off the air source. Position the measuring cylinder at 10 min 10s, and record the volume of the foam again, to 5 ml.
ASTMD 892 foam Tendency Test
3. Pour the second sample into a clean measuring cylinder so that the liquid level reaches 180 ML -. Immerse the measuring cylinder in 93 Immerse at least 900 ml of the scribed line in a 5 ℃ bath. When the oil temperature reaches 93 degrees C 1 C, insert clean gas diffuser and intake pipe, and test the 2 steps. Record the volume of foam at the end of blowing and at the end of static cycle respectively, and accurately measure to 5 mL.
4. the 3 test foam will be destroyed by agitation. Place the test cylinder at room temperature, cool the sample to less than 43.5 ℃, and then put the cylinder in a 24 ℃ bath. When the temperature reaches the bath temperature, the clean intake pipe and diffusion head are tested according to the 2 steps. The volume of the foam is recorded at the end of the blowing end and the end of the static period, and the accuracy is up to 5 mL.
Note: if it is viscous oil, standing still for 3h is not enough to eliminate bubbles, it can stand still for a longer time, but the time shall be recorded and noted in the results