electric drum (any type) Quality Management System is in conformity with ... and NGW-S planet gear speed reducers; B and X series of cycloidal planetary gear speed reducers; ZQ, ZD, ZL, ... ZS, and ZSC(A) series of cylindrical gear reducers; WXJ, and WD series, M-type and A-type vertical worm ... drive drums. Recently, S, K, R, F, and T series of modular reducers have come into operation in our company ...