During drilling operation, when a well kick takes place and bit bore is blocked, the by-pass valve can be opened to allow fluid circulation and well killing. Before drilling in a gas formation, the By-Pass Valve shall be located near or on the bit.

Float Valve Sub is an important tool in petroleum exploration and drilling engineering. The float valve sub is connected at upper part of drill bit. The float valve sub is near the bit connecting thread. The float valve sub can also be used at different necessary position of drill string when required. The main application is, when connected with single piece pipe, it prevents mud from coming in and up blocking the hole. When blowout takes place, blowout in drill string will be avoided because nozzle is closed automatically by valve cap of the float valve assembly .

TIANHE Arrow Type Back Pressure Valve is an important tool preventing of blowout.

Inside BlowOut Preventer (IBOP) is a special tool, which can be stripped through the BOP preempt to be connected with the added drilling tools as soon as possible. When the blowout occurs during lifting operations, the IBOP have many advantages in situation such as, high pressure rating, reliable seal, easy application and operation.

Drop-In Check valves prevent return flow during a kick and are suitable for most drilling situations in which return flow through the drill string is a risk and normal operation requires the benefits of a full-bore sub. By preventing upward flow through the drill pipe and allowing fluid to be pumped downward to circulate the well, the valves provide the driller with the means to control the drill pipe pressures when required, significantly improving and simplifying well control.