Start with the stain, not the machine
Three characteristics of the deposit decide the method. Cold, freshly spilled oil is easy and can be handled with warm water and a mild detergent. Oxidised oil that has been baked on by machine heat has polymerised into a varnish and needs heat to soften it. A mixture of oil with abrasive fines, metal swarf or dust forms an abrasive sludge that has to be flushed off rather than wiped, because wiping just drags it across the surface.
That is why steam degreasing equipment works where cold washing does not. Heat lowers the viscosity of the oil and breaks its bond to the metal, and the pressure of the steam jet carries the loosened film off the surface instead of smearing it. In practice most maintenance teams end up with a small set of equipment matched to different jobs around the plant, rather than one universal machine.
The equipment list to build
1. A steam or hot-water cleaning machine for the machines themselves
This is the core item. For a fixed maintenance bay with a 220 V supply, a stationary unit is usually the right choice. The PowerDe HW02 fixed steam cleaning machine is a good illustration of the specification to look for: 6 kW heating power, steam temperature around 160 °C, vapor pressure of 0.8 MPa, an 80 L SUS304 stainless tank, and the option to switch between dry steam and wet steam. Dry steam is what you want on electrical enclosures, panels and areas where you cannot afford standing water; wet steam delivers the heat and volume needed to lift thick grease off a machine base or a guard panel. The listed protection functions — leakage, short-circuit, high-temperature, high-voltage and water-shortage — are exactly the ones a maintenance workshop will care about when the machine is operated by general technicians rather than a specialist cleaning crew.
If the equipment cannot be moved to a wash bay, portability matters more than capacity. Hand-pushed units such as the PowerDe HMW3 hand pushed steam cleaning machine run on a 48 V battery with a 4.5 kW PTC heater and a 50 L clean-water tank, in a footprint of roughly 1150 × 520 × 1030 mm. That size gets through a standard workshop doorway and down an aisle, which is often the real constraint in an existing factory.
2. Containment and recovery for the run-off
Nothing else on the list is as commonly forgotten. Oil and water that runs off a cleaned machine has to go somewhere. You need drip trays and absorbent matting under the equipment before you start, a collection channel or floor bund, and a separate container for the recovered liquid. Discharging oily wash water into the foul drain or the surface-water drain is an environmental offence in most jurisdictions, and the fact that no detergent was used does not change that — the oil is still there. A simple oil-water separator or a contracted waste-fluid collection service is normally cheaper than the fine you risk otherwise.
3. Hand tools for the parts a jet cannot reach
Steam does the heavy work over open surfaces, but scraped-off deposits still need mechanical help. Budget for extension lances and angled nozzles for the jet, a plastic scraper and brass brush for baked-on varnish, and lint-free wipes for final finishing on ways and mating surfaces. Keep the scraper non-ferrous anywhere it can touch a slideway or a sealing face.
4. Personal protection appropriate to hot steam
Steam at those temperatures causes scalds far faster than hot water does. Insulated gloves, long sleeves, safety glasses and closed, non-slip footwear should be mandatory rather than advisory, and the operator needs training on lance handling before being left alone with the machine. Barriers or signage keep other people out of the spray zone.
A practical sequence for cleaning one machine
- Isolate the machine and confirm that electrical enclosures, bearings and encoder areas are covered or protected before any liquid goes near them.
- Dry-remove loose swarf, dust and free oil with absorbent material. Removing the loose layer first stops it turning into sludge the moment steam hits it.
- Apply dry steam to heat the deposit. Work in small areas and let the heat do the softening instead of trying to blast through cold grease.
- Switch to wet steam to flush the softened film, following with the lance in the direction you want the run-off to travel, towards your containment.
- Wipe the surface dry, then apply the machine's normal protective oil or lubricant to any bare metal. Cleaning strips protective film off the surface as well as dirt off it.
- Record what was cleaned, what was used and how the recovered fluid was disposed of. That record is what auditors ask for.
Questions to settle before you specify
Write down the answers to these before asking a supplier for a quotation: is there a 220 V supply at the cleaning point, or does the machine need to run on battery; how far are the machines from a drain or a wash bay; what total area is cleaned per shift; is standing water acceptable on the surfaces involved; and who will handle the recovered oily water. Those five answers determine whether you need a fixed unit, a hand-pushed unit, or a combination of both.
For a first installation in a plant that has no cleaning bay at all, most teams start with one fixed machine at the maintenance area and one battery-powered unit for mobile work, and add containment and hand tools around that. Shenzhen PowerDe Automation Precision Equipment builds both types in its cleaning equipment series and can configure units for a specific workshop layout, so the conversation is worth having with the plant drawings rather than a catalogue in hand.
