Contact Us
Contact Us

1 min read

What is a Full Opening Safety Valve (TIW valve)?

 Facebook - Featured Image - PES-1

There are two types of stabbing valves that must be prepared for well control: Full Opening Safety Valve (TIW valve) and Inside BOP valve (Gray Valve)

In other words, TIW valves are an essential part of any drilling operation.

But what exactly is a TIW valve?

Full Opening Safety Valves

Full Opening Safety Valve or TIW valves are ball valves designed for high-pressure conditions.  These ball valves can hold pressure from both directions. 

TIW  valves are called “Full Opening” because when the ball valve is opened; the flow path has a smooth inside diameter.  The term “Full Opening” does not mean that the valve's ID is the same as the drill pipe's ID.  We offer valves with the same ID as the pipe. 

TIW valves should always be located on the rig floor in the open position.  This is critical because if the well flows through the drill pipe, the valve can be stabbed quickly into the drill string.


  • TIW valves provide a quick, sure shutoff in the string that can repay the cost of the valve quickly as kick protection.
  • TIW valves are designed to hold pressure from both directions
  • TIW valves follow API standards
  • TIW valve's standard Pressure rating can be either 10,000  or 15,000 PSI depending on application.

PES Engineering | Contact Us

Original article by Superior Performance


Safety & Kelly Valves -

What are differences between Full Opening Safety Valve (TIW valve) and Inside BOP valve (Gray Valve)?

About Practical Engineering Solutions


Practical Engineering Solutions will always be dedicated to providing top-notch customer service to meet our industry demands.

We set ourselves apart with our consistency and timely turnarounds. We are always committed to being responsive to our clients, KEEPING OUR PROMISES, making delivery schedules, and standing by our designs!

From conceptdesign, and engineering, to project management and integrity services. We are your gateway to your journey's engineering endeavors. Including oil & gas, hemp & CBD, and food industries.

Providing services focusing in Facilities EngineeringTurn-Key SolutionsHemp FacilitiesFood Plant EngineeringManufacturingEngineering Services and Drafting & Design.

What Different Careers Can You Pursue With an Engineering Degree?

You’ve always enjoyed understanding how things work, and when you read down the list of top-earning degrees, one predominated — engineering. You...


9 Reasons You Need a Structural Engineer

Are you a building owner who is wondering if you need a structural engineer? If so, read on for nine reasons why you should definitely consider...