The tool is typical and dualaction with fewer components.

The tool could be kept in casing head or casing spool,and when in drilling or work over service,BOP,manifold can be press tested through drilling pipe regardless of whether drill tools in hole or not.

API Oilfield Running& Retrieve tool for VR Plug & Back Pressure Valve The tool is typical and dualaction with fewer components.The tool could be kept in casing head or casing spool,and when in drilling or work over service,BOP,manifold can be press tested through drilling pipe regardless of whether drill tools in hole or not BPV(Back pressure valve)derive from back pressure valve.

It means that valve have some functions to obtain some pressure.In fact,the pressure of back pressure valve can be adjusted.It have many systems.We often use fluid metering dosing system,hydraulic control system etc in our company.On the other hand,back pressure valve can be divided into two parts which are adjustment and over current.