RSJ Series Fuel Injection Screw Air Compressor Air Inlet Valve
Advantage
Features:
Normally Closed Intake Valve: Controlled by pressure input, the intake valve opens when pressure is applied.
Piston–type Check Valve for All Series: This design prevents oil injection during emergency shutdown situations.
Optional Unloading and Replenishing Function: Effectively eliminates cavitation noise generated by the main engine.
Integrated Functions: The intake valve integrates a relief valve, a replenishing valve, and a reverse proportional valve. Standard accessories include a solenoid valve and a filter.
Technic Data:
| Technical Parameters: | ||
| Model prefix | RSJ-120 | RSJ-160 |
| Diameter(mm) | 120 | 160 |
| Flow (ms/min) | 16~25 | 25~45 |
| Maximum working pressure (bar) | 15 | |
| Working medium temperature (C) | -20~120 | |
| Working environment temperature (°C) | -20~60 | |
| Non-return function | ● | ● |
| ON/OFF control | ● | ● |
| Stepless flow control | ○ | ○ |
| Uninstall the air supply function | ○ | ○ |
| Solenoid valve power supply | AC220V 50Hz (other voltage are optional) | |
| Solenoid valve certification | CE | |
| Air intake direction | vertical/horizontal | vertical/horizontal |
| ●Standard ○Optional | ||
How to select the right RSJ series intake valve
The RSJ series is a normally-closed intake valve with an integrated piston-type check valve, a relief valve, a replenishing valve and a reverse proportional valve. It is chosen by airend inlet diameter, which follows the air flow — not by motor power alone.
- RSJ-120 — DN120, flow range 16–25 m³/min.
- RSJ-160 — DN160, flow range 25–45 m³/min.
- Rating — maximum working pressure 15 bar, medium temperature −20 to 120 °C, ambient −20 to 60 °C.
- Functions — non-return and ON/OFF control are standard; stepless flow control and the unloading / air-supply function are optional.
- Coil — AC220 V 50 Hz as standard, other voltages on request; the solenoid is CE marked.
- Mounting — the valve can be fitted vertically or horizontally, so it can follow the existing pipe layout.
If your machine runs a 15 bar system, keep the safety margin: the valve is rated 15 bar, so do not fit it to a 16 bar receiver circuit.
Installation and maintenance
- The piston-type check valve is the part that stops oil being pushed back into the intake during an emergency shutdown. Never remove it to “improve flow” — that is what protects the airend.
- Connect the control air to the cylinder port and check that the valve opens fully at unload-to-load transition. A partly open valve shows up as low flow at full load with a normal current draw.
- Fit the filter (differential-pressure or auto-drain version) on the pilot air line, otherwise moisture reaches the solenoid and the spool starts to stick in cold weather.
- After installation, run a load / unload cycle three times and watch the discharge pressure: it should fall to the set unload pressure without a pressure spike, which means the relief valve is working.
Rsj series intake valve FAQ
What is the difference between RSJ-120 and RSJ-160?
Only the bore and the flow range: DN120 for 16–25 m³/min and DN160 for 25–45 m³/min. Everything else — 15 bar rating, temperature range, functions, coil — is the same.
Why does my intake valve have a check valve inside?
So that when the machine stops unexpectedly, oil and air in the airend cannot flow back through the intake and out through the filter. Without it, an emergency stop can push oil into the intake line.
Can I use it on a variable-speed machine?
Yes. Stepless flow control is available as an option, and the valve works with either ON/OFF or proportional control. Tell us the control signal your controller gives and we will match the coil and the pilot arrangement.