Ball-throw internal pressure operated test tools, catalog page 38
Dual Passage Normally Closed Valve
Full-opening kill circulating valve with two circulation passages
Description
The dual passage normally closed valve is a full-opening circulating valve operated by dropping a steel ball and applying tubing pressure. It is mainly used for kill circulation after testing. Compared with the normally closed valve, it circulates the kill fluid deeper and more safely.
Features
- Dual passage design allows direct and reverse circulation between the annulus and the wellhead, as well as circulation from the annulus to the bottom, so kill fluid is circulated deeper and more safely
- Shear pin mechanism keeps the sleeve in the circulating-port-closed position before operation
Operation
To open the circulating ports, drop a steel ball from the wellhead. When the ball lands on the ball seat, apply tubing pressure to shear the pin; the sleeve moves down and opens both circulating passages. Once open, the passages cannot be closed.
