Rock drilling; Extension drill-steel equipment for percussive long-hole drilling; Rope-threaded equipments 7/8 to 1 1/4 in (22 to 32 mm)
Описание (англ.):
Specifies the basic dimensions for equipment. Gives a list of components; tabulates together with figures: shank rods and shank adapters for central flushing; extension rods; wrench flats; coupling sleeves; drill-bits; four-wing bits; left-hand rope threads; hollow hexagonal and round drill-steels.