... drilling ,oil testing ,perforating, oil extraction testing. Manual single ram BOP for cableBOP Model :SFZ12-21Main technical parameters:Bore :2 4 ... (mm)Weight:83kg (182.984LB)Shear ram BOP for cable:mainly used for sealing cables during well drilling, oil testing , perforating ... simple structure: there are manusl and hydraulic in their switches: single-ram, double-ram and three-ram in their structure; ...