Proportional Valves

Unlike a directional control valve, a proportional valve does not simply open and close; the current fed to the solenoid holds the spool in intermediate positions, setting flow and pressure as continuously variable values. These valves are what produce the injection speed profile, the holding pressure steps and the deceleration at mold opening.

They are electronically controlled and sensitive to contaminated oil: the clearance between spool and body is in the micron range. For that reason a significant share of proportional valve failures actually originates in neglected filter maintenance. Before replacing a valve, oil analysis and filter condition should be checked.

Some types carry integrated electronics (OBE) on the valve. Versions with and without OBE may look mechanically similar, but the control connection differs; this distinction must always be stated when ordering.

Part List

The list below gives the part name, manufacturer, manufacturer code and size. Type a manufacturer code or a dimension into the search box to filter it.

Is it time to replace?

• Injection speed changing from shot to shot, part weight fluctuating
• A jolt or delay between the steps of the speed profile
• Pressure not holding although no setting was changed
• A fault LED on the valve electronics, a valve failure warning on the control
• The spool drifting at zero position — movement while the machine is idle

What to send us when you order

1. The full manufacturer code of the valve (with type and size, such as 4WRPE 10 or 4WRKE 16)
2. Whether integrated electronics are fitted (OBE / OBEC) and the connector type
3. Port size: NG06, NG10, NG16 or NG25
4. Command signal: ±10 V, 4-20 mA or digital

Other part groups