The piston compressor, also called a reciprocating compressor, is the default for Australian garages and small workshops. It compresses air into a receiver, shuts off, and waits until the pressure drops. That is exactly how most people use air: a burst on the rattle gun, some grinding, then nothing for twenty minutes.
Our range is SP Tools cast iron, from a 50 litre V-twin through to the 10HP SP50 on a 270 litre tank. If you need to move the compressor around, the wheeled units are the ones to look at. If your compressor never gets a rest, you have outgrown a piston and want a rotary screw.
How a piston compressor works and why it matters
A piston moves in a cylinder, draws air in and compresses it into the receiver. Simple, mature, and cheap to service compared with a screw element. Two things follow from that design and both affect what you should buy.
First, it generates heat, which is why cast iron cylinders matter. Cast iron sheds heat better and survives more thermal cycles than aluminium, which is why the SP pumps use it. Second, it has a duty cycle. The pump needs rest time inside each hour. If yours is running more than resting, it is undersized for what you are asking of it.
Direct drive or belt drive
Direct drive
The motor turns the pump directly. Fewer parts, lighter, less expensive, and louder because the pump spins at motor speed. The SP13-50X, SP14, SP17 and SP1800 all sit here, and they suit intermittent garage and light trade use.
Belt drive
A belt and pulley step the pump speed down, so it runs slower and cooler. Longer life, less noise, and it copes with heavier duty cycles. The SP50 is the belt drive unit in this range. If you use air most days in a working shop, this is the direction to go.
The range
- SP13-50X - 2.2HP, 50 L, V-twin cast iron. Home garage.
- SP14 - 2.5HP, 60 L, V-twin cast iron. Regular home and light trade use.
- SP17 - 3HP, 60 L, V-twin cast iron. Faster recovery on the same tank.
- SP1800 - 3HP, 100 L, triple cast iron. The serious end of the single phase range.
- SP50 - 10HP, 270 L, belt drive, three phase. Commercial workshop duty.
Piston air compressor FAQs
How long can I run one for?
It depends on the duty cycle rating of the model. Piston compressors need meaningful rest time within each hour. Continuous running is what rotary screw compressors are built for.
Single phase or three phase?
The SP13-50X, SP14, SP17 and SP1800 run on standard single phase 240 V. The SP50 needs three phase. Confirm what is at your wall before ordering.
Why cast iron?
It handles heat and repeated thermal cycling better than aluminium, which translates directly into pump life. It is the main thing separating a trade compressor from a hardware store one at a similar horsepower rating.
Do I need a dryer?
If you spray paint, yes, without question. For general tool use a filter and regulator plus regular tank draining will get you a long way, but moisture is what corrodes air tools from the inside.
Do you deliver Australia wide?
Yes, free shipping Australia wide. The SP50 ships on a pallet, so check your delivery access.