Ball Valve Bore Size

Ball valve bore size is the diameter of the hole through the ball inside the valve.  This size determines the flow capacity through the valve when it's in the open position.  The bore size can vary widely depending on the valve type, pipe size, and application requirements.

Bore Size Classifications

Full Bore (Full Port)  -  Open completely, which create an unobstructed path for gases or liquid being pumped through a tube or pipe.  The width of the flow channel in a full bore ball valve is equal all through from the inlet to the outlet. 

• Bore Size  -  Matches the inner diameter of the connecting pipeline.
• Purpose  -  Provides maximum flow with minimal restriction, resulting in a negligible pressure drop.
• Example  -  In a 2-inch full bore ball valve, the bore size will be around 2 inches (matching the pipe).

Reduced Bore (Reduced Port)  -  Ball bore diameter less than the pipe diameter.  Flow through the valve is one pipe size smaller than the valve's pipe size resulting in flow area being smaller than pipe.

• Bore Size  -  Smaller than the inner diameter of the pipeline.
• Purpose  -  Creates some restriction in flow, leading to a slight pressure drop.
• Example  -  In a 2-inch reduced bore valve, the bore size may be around 1.5 inches or less.

V-Port Bore  -  A V-port ball valve is a control valve with a V-shaped seal or V-shaped ball.  The "V" shape allows for better fluid control.  The molded V-bore differentiates the V-port ball valves from other ball valve types.  The V bore can be available in either a 15⁰, 30⁰, 45⁰, 60⁰, or 90⁰ angle.

• Bore Size  -  The opening is V-shaped, rather than round.
• Purpose  -  Allows more precise flow control and throttling.
• Example  -  The V-shaped bore can be customized depending on the flow control needs, often requiring specific designations based on the flow characteristic.

Bore Size Selection  -  When selecting a ball valve, it’s crucial to choose the bore size based on the flow rate, pressure requirements, and specific needs of the system.

Pigs Through a Ball Valve  -  A full bore valve has an opening that is equal to the nominal pipe size (NPS) of the flowing pipe.  These valves are the ideal solution where pressure drop is a concern.  Full bore valves are the ideal choice where pigging of process lines is a major consideration.  Normal "dumb" pigs may be able to deform across a reduced bore ball valve.  Smart pigs, however cannot.  Full port valves are normally used when inserting sample probes, injection quills or interface probes to facilitate removing the device from the system while under full line pressure.