... valve rubber, rubber filter, rubber compensator air flue compensator, flexible hanger, rubber shock pad, shock absorber, pipe damper, seal, gate ... flange or loose joint ,used at shock absorber and compensate for displacement.JGD mean single ball (arch),JGD-A dual ball ,JGD ... of air, compressed air, water, sea water, oil, acid and alkali. Special type used to transport -30 to 250 centigrade of the ...