Class 150 Ball Valve

About Class 150 Ball Valve

A Class 150 ball valve is a quarter-turn isolation valve designed and manufactured to meet ASME Class 150 pressure rating standards. It is widely used in low to medium pressure piping systems for reliable shut-off control of liquids, gases, steam, and other process fluids.

What Does Class 150 Mean?

Class 150 refers to the pressuretemperature rating defined by the American Society of Mechanical Engineers (ASME) under standard B16.34.

• Maximum pressure at 100F (38C): approx. 285 PSI (19.6 bar) for carbon steel

• Pressure rating decreases as temperature increases

• Flange dimensions typically follow ASME B16.5

This class is commonly used in general industrial service applications.

Working Principle

A Class 150 ball valve operates using a spherical ball with a bore through its center:

• Open Position Bore aligned with the pipeline, allowing full flow

• Closed Position Ball rotated 90, blocking flow completely

The quarter-turn mechanism ensures fast and tight shut-off.

Main Components

• Valve Body Cast or forged carbon steel, stainless steel, or alloy steel

• Ball Precision-machined stainless steel or chrome-plated steel

• Stem Blow-out proof design

• Seats PTFE, RPTFE, or metal seats

• End Connections Flanged (most common), threaded, or welded

• Operator Lever, gear operated, or actuator (pneumatic/electric)