National Oilwell Varcos BX 5 Elevator improves both rig sagety and efficienct. Since the introduction of the BX1 and 2 elevators engineers have continuously striven to improve the operation reliability and safety of its ......National Oilwell Varcos BX 5 Elevator improves both rig sagety and efficienct. Since the introduction of the BX1 and 2 elevators engineers have continuously striven to improve the operation reliability and safety of its design. Special Features: One door bushing is spring loaded with linkage connecting it to a locking pin. Any load on this bushing segment engages the pin preventing the elevator from opening. This safety lock prevents the elevator from opening under load. The elevator is prepared for an interlock system when used with a power slip for tripping. The hydraulic cylinders are located inside the body for clean lines and maximum protection and they are still accessible for normal maintenance. Bushings can be changed within 5 minutes with no special tools and no loose nuts, bolts, or pins.