When we think of a ball valve, we usually imagine a simple on/off device. But not all ball valves are made just to open or close the flow. The segmented ball valve — also known as a V-ball or V-port valve — is a specialized design created for precise flow control. It combines the tight shutoff of a ball valve with the modulating control of a control valve, making it ideal for industrial applications that require both performance and precision.
A segmented ball valve is a quarter-turn valve featuring a partially contoured ball.
Instead of having a perfectly round bore, the ball includes a V-shaped notch or segment. As the valve opens, this shaped opening allows the flow to increase gradually and predictably rather than all at once.
This design gives the valve a more linear flow response — providing fine control at low openings and high capacity when fully open. It retains all the advantages of a traditional ball valve — tight shutoff, compact size, and quick actuation — while adding excellent throttling capabilities.
The sharp V-shaped edge of the segment also has a self-cleaning effect. As it rotates, it cuts through fibers or debris in the flow, preventing clogging — an essential advantage when handling slurries or viscous fluids.
A standard ball valve is meant for on/off service, not for flow regulation. When partially opened, a traditional round-bore ball valve creates a turbulent, non-linear flow that can erode the seats and shorten its lifespan.
A segmented ball valve, on the other hand, is engineered for throttling and modulation.
The V-notch allows for a more proportional flow control, giving the valve a linear or equal-percentage response. This results in smooth, predictable performance across the full range of opening angles. Built with reinforced or metal seats, segmented designs can withstand high pressure drops, abrasive fluids, and still maintain tight shutoff — often up to ANSI Class IV or V standards.
Segmented ball valves offer a unique combination of control precision, durability, and high flow capacity in a compact design.
They are smaller and faster to actuate than traditional globe control valves, reducing both installation space and maintenance requirements.
Thanks to their shearing and self-cleaning action, segmented valves are widely used in demanding industries such as:
Segmented ball valves solve a key industrial challenge: achieving accurate flow control without sacrificing tight shutoff and robustness.
They help plants improve process efficiency, product quality, and safety, while reducing downtime and maintenance costs.
GEMELS S.p.A., a leading manufacturer of industrial ball valves, designs and produces high-performance segmented ball valves for applications requiring precision, reliability, and long service life.
With decades of expertise in hydraulic and industrial systems, GEMELS engineers support companies in selecting the optimal valve for smooth, efficient, and controlled operation in every application.