COMMON VALVE TYPES
Pinch Valves
The families that appear on first RFQs and Chinese export quotes. Shared names are not interchangeable designs.
Choosing Pinch Valves
A pinch valve closes by compressing a flexible sleeve. In sleeve-based designs the sleeve is the wetted component, so its material and construction are central purchasing fields. Shut-off and control versions may require different sleeve geometry and operating calculations.
What to include in the RFQ
- Describe the slurry chemistry, solids, temperature, pressure and cycle frequency.
- Request sleeve compound, reinforcement and any vacuum-service requirement.
- Separate full-open isolation from continuous control, including the required operating range.
- Confirm spare-sleeve availability, replacement access and actuator requirements.
A published design example
Flowrox PV/PVE-family designs use pinch bars to close a sleeve; conical and vacuum sleeve options illustrate distinct configurations rather than one universal sleeve.
Selection scenario
For an abrasive transfer line, compare a replaceable-sleeve design against the fluid and shutdown schedule. Include periods of vacuum or suction if present; a sleeve selected for positive pressure alone may be the wrong configuration.
Common selection mismatch
Rubber sleeve is not a complete material specification. Neither a published service-life claim nor a control characteristic should be generalized to every compound and process.