Patent for preparing wear-resistant plate with graphite copper powder

The copper ring is equipped with J20 1 graphite carbon brush, and the steel ring is equipped with J 164 or J204 copper-containing carbon brush. I have been selling motors and accessories for 10 years. This is the first time I've heard of pig iron slip rings. Pig iron is only the link part between the inside of the slip ring and the shaft, depending on which three rings are outside and which is the conductive part of the slip ring.