Specification Review
directional control valve
Resolve the configuration, accessory boundary and acceptance record before selecting a directional control valve supplier. The decision is whether spool center, coil supply and mounting accessories are written as one assembly, not whether a brochure lists a family. This page does not offer an unsupported engineering or compliance claim. Control Valve Sourcing only lists the questions factories must answer for a comparable quote.
Decision dossier
Acceptance basis
- Acceptance basis: Design input
- Buyer input should name NG size, mounting pattern, spool type, center condition when de-energized, supply and tank port ratings, fluid and viscosity, coil supply, quantity and destination. Are positioner, feedback and mounting accessories supplied as one assembly? If the circuit uses a simple on/off coil, say so instead of copying a process-valve positioner line. Footprint of the subplate and spare coils belong in the same packet when they affect the order.
- Supplier answer
- The factory restates spool identity, de-energized flow paths, coil code, mounting kit, and which leak or shift tests apply to the delivered serial. Ask whether the quoted item is a valve only or a valve plus subplate, wiring and feedback switch. FAT language, if any, must name the oil, pressure and actuator used on the stand.
- Open deviation
- Typical gaps are an unsigned center condition, missing tank-port rating, accessories priced after the fact, or a process-valve noise note used as if it applied to a spool. Those remain open until the named factory answers. This site does not close deviations by asserting a standard.