Cast iron piston compressor WK550-4-0/100P input power 3 kW, intake 530 l/min, pressure 10 bar, air receiver 100 l, voltage 400/50 V/Hz

Product detailed description

WALTER Cast-Iron Piston Compressor - WK550-4,0/100P

The WK550-4,0/100P features a three-cylinder cast-iron unit in a 3W configuration mounted on a compact 100 l tank. The power input is 3.0 kW, with an intake of 530 l/min and an effective delivery rate of 440 l/min at 10 bar, with a unit speed of 1,202 rpm. It is powered by a three-phase 400 V / 50 Hz supply, with noise levels of approximately 80 dB(A), and a 3-year warranty upon registration at waltercesko.cz.

It is the smallest and most mobile horizontal machine in the 3.0 kW class: you get a full delivery of 440 l/min without a bulky tank that would turn the compressor into a permanent fixture. It is designed for spaces where room is limited or where the machine must be moved to the work — as a powerful second source for larger operations, for assembly sites, or for workshops with heavy but intermittent demand.

Configuration of this machine

• Cast-iron unit — 3W · 1,202 rpm · single-stage compression
• Pressure vessel — 100 l · horizontal
• Horizontal design
• Three-phase 400/50 V/Hz
• Standard pressure of 10 bar for common pneumatic tools

Why choose this model

Who is it for

Typical buyers include auto repair shops or metalworking facilities that already own one compressor and require a second, full-performance source for a remote station, or workshops with limited space that refuse to compromise on power. It also suits installation companies with a fixed base that need 440 l/min for tools but lack a permanent location to bolt down a compressor. Conversely, those planning continuous air consumption for hours should opt for the same unit with a larger tank — with 100 l, the machine will cycle frequently.

Typical applications

• 1/2" impact wrench and blow gun at a single service bay
• Random orbital sander with pauses between operations
• HVLP spray gun for minor paint repairs
• Drills, ratchets and staplers at an assembly workstation
• Air source for a remote station in a larger operation
• Temporary workstation to which the machine can be wheeled across the workshop

When to choose a different model

What the figures tell you — calculated values

The values are calculated and are meant for comparing the models with each other, not as guaranteed figures.

Design and technology

Related models and alternatives

Frequently asked questions

Why only 100 l for a 530 l/min intake?

Because it is a deliberate compromise in favour of compact size. The recommended ratio is 0.3 to 0.5 litres of tank capacity per 1 l/min of intake; for 530 l/min, this is approximately 160 to 270 l — the 100 l volume falls below this range. In practice, this means more frequent motor switching in exchange for the smallest horizontal build in its class. If the machine will run continuously, choose a larger tank: the 200 l and 270 l sizes from our range fall within the recommended band.

Is 1,202 rpm still considered a slow-running machine?

Yes, it is. Typical high-speed aluminium units operate in the 2,000 to 3,400 rpm range, so this machine has roughly half to a third of that rotational speed. Within the WALTER range, 1,202 rpm is in the faster half — the slowest is the high-pressure HWK1200-10/500P-15P at 688 rpm. In practice, you will notice this in the longevity of the rings and bearings — a hobby unit with triple the rpm has a lifespan in a completely different order of magnitude.

Can it handle a pneumatic angle grinder?

It depends on the type. Random orbital sanders and chipping hammers consume 300 to 450 l/min continuously, so they fit within the 440 l/min delivery, except for the most demanding models at the upper limit of consumption. However, a pneumatic angle grinder draws 400 to 600 l/min, and for the more demanding ones, the pressure will drop — the 100 l reserve will only cover this for a short time. For continuous grinding with an angle grinder, a higher class of machine is appropriate.

How quickly does the tank fill?

The calculation gives approximately 2.3 minutes from zero to 10 bar without draw-off — the fastest filling among horizontal machines in the 3.0 kW class; the vertical VWK550-4,0/90P with a 90 l tank is slightly faster. This is an isothermal estimate based on the formula: tank volume multiplied by pressure divided by effective delivery; actual filling is usually slightly longer.

Can it be moved between workstations?

Yes, on a flat floor; the wheels and handle are provided for this purpose. However, it is not a portable machine — the cast-iron unit and pressure vessel have significant weight, and you will need assistants for stairs or loading into a car. After every move, ensure the machine stands on a level surface and check the oil level.

The machine comes with a 3-year warranty after registration with the importer. Warranty terms, the maintenance schedule and a comparison of all 28 models are in the category WALTER cast-iron piston compressors.