AUTOMATION

What is a Proportional Valve? Applications

The operating principle, advantages, and industrial application areas of proportional valves in hydraulic and pneumatic systems.

December 10, 2025

12 min read

BRS PROSES Engineering Team

A proportional valve isn't just a component - it's the bridge that makes a system automatic and precise, turning an electronic signal into mechanical motion, and that motion into controllable flow.

1. What Is a Proportional Valve

A proportional valve gradually changes its opening in proportion to an incoming electrical signal. Unlike a classic on/off valve, it can move through infinite intermediate positions, enabling precise flow or pressure adjustment.

2. Application Areas

Sector	Application	Proportional Valve's Role
Plastic Injection	Mold filling	Real-time tracking of speed/pressure profile
Test Rigs	Fatigue testing	Programming dynamic force profile via software
Dosing Lines	Liquid/powder filling	Gradual push-speed adjustment
Textile Machines	Yarn tension	Constant tension control

Plastic Injection Machines: injection speed and pressure differ at every stage of mold filling; a fixed valve can't provide this precision
Test Rigs: when a load must follow a specific curve, software programming replaces a mechanical cam
Dosing Lines: push speed of liquid/powder is adjusted gradually, directly affecting fill precision

"The precision a proportional valve offers is only meaningful when paired with proper sensor feedback and a control card of sufficient resolution."
— BRS PROSES Engineering Team

3. BRS Proses Application Support

Application-specific valve and control architecture design
Sensor feedback integration
PLC/control card resolution compatibility check
Field commissioning and calibration