Castair R30312VG30 — 30 HP Rotary Screw Air Compressor
The Castair R30312VG30 is a 30-horsepower, 3-phase rotary screw air compressor built for shops that need continuous, reliable air. It delivers 130 CFM at 100 PSI on a 120-gallon vertical tank, with a 100% duty cycle rating. If you run impact guns, paint booths, lifts, tire machines, or any other pneumatic equipment all day long, this compressor is built to keep up.
Specifications
| Spec | Value |
|---|---|
| Horsepower | 30 HP |
| Phase | 3-Phase (also available in 230V or 460V configurations) |
| Tank | 120 Gallon, Vertical |
| CFM Output | 130 CFM @ 100 PSI |
| Standard Pressure | 135 PSI (up to 175 PSI available on request) |
| Dimensions (L x W x H) | 44" x 32" x 73" |
| Weight | 1,065 lbs |
| Duty Cycle | 100% |
| Model Number | R30312VG30 |
Operation
- Single solenoid operates the air end — no computers, no complicated controls
- Easy-to-read pressure and temperature gauges are standard
- High pressure and dual high temperature automatic shutdown protection
- Factory filled with 4,000-hour (or one year) synthetic lubricant
- Pressure ranges up to 175 PSI available on request (135 PSI standard)
- 10-minute auto shut-down timer — saves electricity when no air is being used
Maintenance
- Built-in air/oil separator with spin-on filter
- Hour meter standard for easy service tracking
- Off-the-shelf V-belts with adjustable belt tightener
- Spin-on oil filter and automotive-type paper element air filter
- Air and oil lines use standard copper piping — no proprietary parts
- Air-cooled aftercooler and oil cooler, easily removable for cleaning
- Heavy-duty industrial 1,725 RPM motors with full 15% service factor
Why Castair?
Castair has been building compressors since 1991. Their pumps are cast iron — not aluminum. Oil-lubricated, not oil-less. They run at slow RPMs, which keeps them quiet and extends service life. Every component that wears is an off-the-shelf part, so you are never waiting on proprietary replacements.
As they put it: "Compressors Built Like They Used to Be."
Warranty
2-year warranty on air end, electric motor, and tank.
Shipping
This unit will ship within four weeks of order placement. All orders receive a courtesy call to confirm conditions and application to ensure the correct product has been purchased.
Call 866-217-0063 for quick answers and help!
Frequently Asked Questions
What is the duty cycle on the R30312VG30, and how does it differ from a reciprocating piston compressor?
The R30312VG30 rotary screw runs at 100% continuous duty cycle — it is designed to produce compressed air all day without stopping to cool down. A piston compressor typically runs at 50–75% duty cycle, meaning it needs off-time to dissipate heat from the compression cylinders. If your shop runs air tools, paint equipment, or pneumatic automation for extended shifts, the rotary screw design of this Cast Air unit eliminates the capacity bottlenecks you'd hit with a comparable piston machine.
What CFM output does the R30312VG30 deliver, and what tools or equipment can it support?
This 30 HP unit produces approximately 125 CFM at 125 PSI, which is enough to run multiple simultaneous high-demand tools — think 1" impact wrenches, DA sanders, plasma cutters, or continuous spray gun work without pressure drop. It can also support light industrial automation, sandblasting cabinets, and multi-station air lines in a production shop. If you need to verify your exact CFM requirements against your tool roster, call us at 866-217-0063 and a tech can walk through the load calculation with you.
What electrical service does the R30312VG30 require, and is a dedicated circuit necessary?
The R30312VG30 is wired for 230V three-phase power and draws approximately 80–90 amps at full load on a 30 HP motor, so you will need a dedicated 100-amp 3-phase circuit with appropriately sized wire runs per NEC guidelines for the distance from your panel. This is not a unit you can plug into a standard 230V single-phase outlet — if you are converting from single-phase or adding service, have a licensed electrician size the panel feed before the compressor arrives. Three-phase is standard in most production and auto body shops; if you are running single-phase only, Cast Air offers single-phase configurations in other models.
How often does the oil need to be changed on the R30312VG30, and what maintenance does the rotary screw require?
Cast Air rotary screw units typically call for an oil and oil filter change every 2,000 hours under normal operating conditions, along with air/oil separator element replacement at the same interval — significantly less frequent than a piston compressor that may need oil changes every 500–1,000 hours. You will also want to check the inlet air filter every 500 hours and replace as needed based on your environment (dusty shops will shorten that interval). The cast iron airend on this machine is built for long service life, but staying on the 2,000-hour maintenance schedule is what keeps the warranty intact and the airend running efficiently.
How loud is the R30312VG30 compared to a piston compressor of similar horsepower?
The R30312VG30 operates at approximately 70–72 dB(A) at one meter, which is noticeably quieter than a 30 HP two-stage piston compressor that typically runs 80–85 dB(A). The rotary screw design produces a steady, lower-frequency hum rather than the loud reciprocating pump strokes of a piston unit, which makes a real difference in shop communication and operator fatigue over a full shift. If the compressor is going into an enclosed mechanical room rather than an open shop floor, the noise reduction is even less of a concern.
