Difference Between Floating and Trunnion Ball Valves

Floating and trunnion mounted ball valves are two of the most common designs used in industrial piping systems. The main difference lies in how the ball is supported and how pressure is handled, which affects performance, size range, and application suitability.

Floating Ball Valves

• The ball is held in place by the seats and floats slightly downstream under pressure
• Simpler and more compact design
• Generally used in smaller sizes (typically up to 6–8 inch)
• Lower cost compared to trunnion valves
• Excellent for moderate pressure applications
• Good sealing performance with lower torque

Trunnion Mounted Ball Valves

• The ball is mechanically anchored by a trunnion (shaft) at the top and bottom
• Better suited for larger sizes and higher pressure applications
• Lower operating torque, especially in large valves
• More robust sealing under high pressure differentials
• Often used in critical service, high-pressure, or large-diameter pipelines
• Usually more expensive than floating designs

Quick Comparison

• Size Range: Floating = smaller sizes; Trunnion = larger sizes
• Pressure Rating: Floating = moderate; Trunnion = high pressure
• Torque: Floating = higher in large sizes; Trunnion = lower
• Cost: Floating = generally lower; Trunnion = higher
• Best For: Floating = general service; Trunnion = critical/high-pressure service

 

Still unsure which design is right for your application? Call 908.362.9981 or submit the inquiry form and we’ll help you choose the best ball valve type.