... sales, rental. maintance service for all types of tower craneDetailed Product Description1. Topkit tower crane : Jib lenght (30-80M); Max under hook ... products with16 Manganese,40 Chromium and 45#steel etc .4,Every parts of our products that pins ,axles, ... 3 ) Slewing bearing : appointed corporation of Fangyuan SlewingBearing Factory .( 4 ) Slewing mechanism : equipped with four-speed winding motor and ...