1. What actually came off, and what did not
Sort the surfaces you cleaned into three columns: removed in the planned passes, removed with extra passes, and not removed. The middle column is the interesting one, because it tells you where the method needs more heat, more dwell or a different mode rather than more labour. A shop that cleaned a guard, a way cover, a chuck housing and the sheet-metal inside a splash panel rarely gets the same result on all four, since painted sheet, cast iron and stainless hold soil differently.
Judge the result against the criterion set before the wand was picked up — a white cloth wiped over the surface showing no oily film, or the sheen on a cleaned guard no longer showing a streak pattern. Comparing against memory is how a trial gets over-claimed to a purchasing manager and then fails on the first production clean.
2. Time and labour against the window you can actually use
Add up the real elapsed time, not nozzle time: masking, moving the machine or the unit, cleaning, drying, re-inspection and hand-back. That total is what production gives up, and it is the number a shutdown plan is built around. Then compare it with the window you have on a real week — a changeover, a weekend block, a planned maintenance slot. If the trial took three hours and the shop only has ninety minutes, the method is not finished; it needs splitting by surface, or a second operator, or a shorter task list.
Record who did the work and what they had to be told during the trial. If an operator needed coaching on distance or dwell, that belongs in the written method before the trial is called a pass.
3. Mode, distance and dwell — the settings that explained the result
Write down which mode did the work. Dry steam carries heat with very little free water, which is what you want around electrical housings, control bezels and anywhere standing water is unwelcome. Wet steam and hot water carry the volume needed to flush loosened soil off a guard or a floor plinth. Where the trial used both, note which one released the deposit and which one cleaned up afterwards — that pairing is the method, not either mode alone.
Machines in the Cleaning Equipment Series are built around switching between dry steam, wet steam and hot water on the same unit, which is why the same machine can handle an oily housing and then the floor beneath it. For a fixed position with mains services, the PowerDe HW02 steam cleaner detail page lists a 6 kW heater, a 160 °C steam temperature and 0.8 MPa vapour pressure on a 220 V supply with an 80 L SUS304 tank; those are the published figures to compare against the working envelope your trial needed, rather than assumptions about what "high pressure" means on a datasheet.
If your trial area sits away from a fixed service point, the same review should cover the mobile driving style steam cleaner in the PWD line, which carries its own water tank, offers dry steam, wet steam and hot water on one unit, and can be supplied with or without a battery. Whether a fixed or a mobile unit fits is decided by your own utilities, not by the machine's specifications.
4. What the run-off carried, and where it went
Steam and hot-water cleaning use far less water than a hose, which is the point of them. But the water that does leave a machine-shop trial carries cutting fluid, way oil and fine swarf, and a floor drain is not automatically a lawful route for it. Review how much liquid left the trial area, what it contained, and whether it reached a drain, a bunded pad or a recovery container. If nobody on the trial could answer that, the environmental owner needs to be in the review meeting before the method is scheduled.
Make the recovery step part of the written method — a tray under the trial zone, an absorbent stage, an extraction pass — and name who empties it. This is usually the item that delays a cleaning change by weeks, not the cleaning itself.
5. Whether anything downstream was affected
A cleaning method that leaves the machine looking good but causes a fault downstream has failed, whatever the photographs show. Before the trial is signed off, check the items that steam can affect: enclosure seals and cable entries in the wetted zone, wiper seals on way covers, the bearing points that were stripped of oil film, and any retrofitted scale or optical enclosure that sat inside the spray path. Repeat the builder's own checks, then watch the first warm-up and the first few cycles for alarms, unusual noise or smells, and check that a cleaned way cover still takes its sealant and a cleaned fixture face still seats squarely.
Corrosion is the other downstream item. Flash rust on bare cast iron or on a machined fixture face shows up hours after a wet clean, so re-inspect the next morning rather than only at hand-back. Where the trial left the surface bright and then dull, note it — that is a finding about the method, not about the machine.
6. Whether the site can supply what the machine needs at full scale
A trial run at one bay proves nothing about the other eleven. For each position you want to clean, confirm supply voltage and breaker rating at the socket, the length of the hose run from a tap to the bay, floor space for the machine footprint, and the route the unit has to travel. Compare those against the published parameters on the product page rather than against the impression from a demonstration. As a reference for what to measure, the HW02's published footprint is 1,200 × 800 × 1,200 mm including handles, with a four-point internal-tooth tap-water inlet; a hand-pushed unit in the same series is listed at 1,150 × 520 × 1,030 mm on a 48 V battery. Those two descriptions answer completely different site problems.
Check your mains water hardness at the same time. Scale is the long-term failure mode of any heated water system, and a softening or filtration step agreed before installation is cheaper than the first service call.
7. The protections you relied on, and the ones you assumed
Operators working with high-temperature, high-pressure steam lean on the protection package. The product pages in this range list leakage, short-circuit, high-temperature, high-voltage and water-shortage protection; the wording differs between models and pages, so confirm item by item for the specific unit you are evaluating rather than counting the entries. In daily use, water-shortage protection is the one that matters most, because running a heater dry is the most common way a steam machine fails in service. A machine that trips one of those protections during a shift should be reported, not reset repeatedly.
Then check what the protections do not cover on your side of the interface: the operator's PPE, a locked trigger on the lance, barrier tape around a wetted zone, and a written method statement for a shop where other people are working nearby.
8. Whether the trial specimen was representative at all
This is the review question most often skipped, and it is the one that overturns a decision. Was the trial piece the worst case or the friendliest one? A housing that had been dirty over a weekend shutdown is closer to reality than a panel wiped that morning. One soil type proves one result: neat cutting fluid, dried coolant sludge, rolling oil and graphite fines respond differently to heat, and a trial that used only one of them cannot claim to cover all of them.
If the trial passed on a light specimen, either re-run on a heavy one or treat the decision as unproven. A second specimen costs an afternoon; a method that fails across a whole shop after purchase costs far more.
9. The comparison against the current method, in your own numbers
Put the trial beside what the shop does today, using figures from your own records rather than estimates: labour hours per clean, detergent and chemical spend, water volume, how long the machine stays out of service, and how often the same surface needs re-doing. A single trial produces one line in that table; it takes two or three repeats on different specimens before the line is stable enough to justify a purchase. Write the baseline in the same units you will measure after installation, otherwise the comparison will be argued rather than read.
10. What to hand over, and what to send back to the supplier
A finished review is not a verdict; it is a sheet. It names the surfaces cleaned, what was masked, the mode and distance and dwell used, the elapsed time, how run-off was recovered, the pass check and who signed it, plus before-and-after photographs taken from a similar distance and light. That sheet goes into the maintenance schedule next to the machine it belongs to. A trial that ends in someone's notebook gets re-invented badly at the next shutdown.
Send the same package — before photograph, description of your fluids, the pass criterion, the access you can give a nozzle and the drying time you can allow — back to the supplier, and ask them to test your soil rather than a demonstration panel. If your parts, enclosure layout and duty cycle look unlike the vehicle-cleaning and disinfection uses written on the current product pages, raise that directly and ask about customized steam cleaning equipment instead of assuming a catalogue model fits. PowerDe also lists engineering services covering hardware testing for cleaning equipment, so an unusual specimen or duty cycle can be discussed at enquiry stage rather than accepted as out of scope.
Send the review sheet to sales@powerde.net or call +86 13023198376, and you will get a configuration matched to the trial rather than a brochure.
Frequently asked questions
How many trials before a method is accepted? One specimen answers one question. A method is normally accepted after it has passed on two or three different soils and surface types, and after the same sheet has been repeated by a second operator.
What if the trial failed on one surface only? That is a usable result. Record the surface, the deposit and the settings that were tried, and treat it as an open item: change the mode, the dwell or the pre-treatment for that surface and re-run it, rather than closing the trial or discarding the method.
Who needs to be in the review? Maintenance owns the machine condition, production owns the downtime, and the environmental or compliance owner owns the run-off. A review held by the person who ran the trial alone will miss the one constraint that stops the method being scheduled.
