Qualified products shall meet the following conditions:
1. The code mark on the end face is consistent with the requirement.
2. The surface is flat and smooth, without any defect or deformation.
3, with the framework of the rubber oil seal shape is correct, the end face is round, put on the glass plate should be connected with the glass surface, no interference phenomenon.
4, no skeleton oil seal outer edge should be straight, flat face, with the hand to deformation, release the hand can be restored to the original shape.
5. The shape and thickness of the cutting edge should be the same on the whole circumference. The cutting edge should be closely fitted on the neck of the matching equipment when it is fitted with the fittings.
6, with a spring rubber oil seal, the spring should be no rust, no deformation, and can be firmly stuck in the spring groove.Take 50*72*12 rubber oil seal as an example.Make the oil seal fall to the ground freely from the height of 1m. If the spring falls off no more than 1 time every 5 times, it can be considered that the spring is in good cooperation with the oil seal.
7. When the distributor buys rubber oil seals in bulk, he/she may first take samples for oil immersion test and measure the rate of mass change.For example, after soaking the oil seal with no. 25 transformer oil at (70±5) ° c for 24h, the mass change rate should be between 3% and 5%.