Oil Particle Counter on Rent (NAS Checking Machine)
Ram Engineering rents out a portable laser particle counter that tests oil samples at your site and gives an ISO 4406 code and a NAS 1638 class.
What the Counter Does
The counter is a portable laser (optical) particle counter. It sizes and counts the particles in a bottle sample and reports them as a cleanliness code, so you can read on site, without waiting for a laboratory report, how the oil compares with the class your specification sets.
It tests offline only. The oil is drawn into a clean sample bottle and counted from the bottle; the counter is never connected to a running line.
We count bottle samples on it in our own oil flushing, pipeline flushing and oil filtration work. On a 2025 pipeline flushing job at an aluminium plant in Andhra Pradesh, bottle samples from the return line were counted until the counts met NAS 4 on repeated samples.
Our Counter Testing a Sample
This short clip shows our own counter testing an oil sample from a bottle. The oil runs through the counter, and the screen shows the cleanliness codes as it counts.
The clip has no sound.
The Counter Up Close
How a Laser Counter Counts, and What Can Upset a Count
Light blocking is the usual principle of laser counters for oil. The sample passes through a narrow cell, a laser beam shines across it, and each particle shades the detector; the size of the shadow gives the size of the particle.
Anything that shades the beam is counted. Water droplets and air bubbles count as particles, very dark oil can block the light, and in very dirty oil two particles passing together can be read as one larger one.
So tell us if the oil may be wet, foamy, very dark or very dirty. Before the counter is booked we say whether it suits your oil, or whether a laboratory test would serve you better.
When Renting the Counter Suits, and When It Does Not
As a general guide:
- Suits: checking on site that a flushed or filtered system has reached the class in your specification, before it goes back into service, where your specification accepts a portable counter’s count.
- Suits: checking new oil before it goes into a system, where your specification sets a class for it.
- Suits: counting on set days, when you do not need a counter of your own.
- Does not suit: watching a running line. The counter tests bottle samples only.
- Does not suit: a full check of the oil’s condition. A particle count shows only the particles; water content, viscosity, acid number and wear metals need other oil analysis tests, many of them in a laboratory.
Details
Rental Terms
Written terms are issued with every quotation.
| Item | Terms |
|---|---|
| What it tests | Bottle samples of oils such as hydraulic and turbine oil, counted offline at your site; never a running line. We confirm in writing whether it suits your oil. |
| Cleanliness codes | An ISO 4406 code and a NAS 1638 class for each sample. |
| Charging basis and rental period | Stated in the quotation. |
| Who takes and counts the samples | Agreed in the quotation. |
| Sample bottles | Agreed in the quotation. |
| Transport to your site | Quoted for your site location. |
| Power and space | Confirmed with the quotation for your site. |
| Results and report | Agreed in the quotation. |
What Your Site Provides
Our past offers put these in the customer’s scope; your offer confirms them.
- Permits, gate passes and entry to the machine.
- Safe access to each sampling point, with the system running when a sample is drawn.
How Renting Works
The Job and the Dates
Tell us the oils, the code and class your specification sets, the sampling points, the site and the dates.
Suitability Check
We check that the counter suits your oil and gives the code you need, and say so in writing.
Written Quotation
It states the days, who takes and counts the samples, the transport and how the results reach you. The booking follows your order.
Counting at Your Site
Bottle samples from the agreed points are counted offline on the agreed days, and the results are handed over as the quotation states.
What You Get From the Counts
Each count gives the cleanliness of one bottle sample as an ISO 4406 code and a NAS 1638 class. Counts from the same point over the days of a job show whether the oil is getting cleaner, and when it holds the class.
How the results are recorded and handed to you, and whether a report comes at the end, is agreed in the quotation. On our own flushing jobs, each sample’s count goes into the flushing log for its circuit.
A count can be no better than the sample behind it: use a clean sampling bottle, flush the valve with a little oil first, sample at the same point each time while the oil flows steadily, and shake the bottle again just before the count, because particles settle. Follow your plant’s sampling procedure: the oil may be hot and under pressure.
What to Send for a Rental Quote
Enough to start:
- The oils: each oil you want counted, with its type and viscosity grade.
- The code and class: ISO 4406, NAS 1638 or both, and the class your specification or machine maker sets.
- The samples: how many machines or sampling points, and about how many samples.
- Water or air: whether the oil may hold free water or air bubbles.
- The job: what the counts are for, such as the end of a flush, a filtration job or new oil.
- The site and the dates: where the samples will be counted, and the days you need the counter.
- Earlier results: send your latest oil report if you have one.
Rent a Counter, or Buy One
Renting suits counting on set days. If your plant counts oil often, on a schedule, a counter of its own may serve it better.
We also supply portable laser particle counters. We are a supplier, not the maker.
Questions Buyers Ask
Does the counter test oil in a running line?
No. It tests oil samples in bottles, offline, and is never connected to a running line.
Which cleanliness codes does it give?
An ISO 4406 code and a NAS 1638 class for each sample. If your specification uses another code, say so when you enquire, and we confirm in writing whether the counter gives it.
Can it count dark, thick, wet or foamy oil?
Tell us about the oil first. Droplets and bubbles are counted as particles, very dark oil can block the light, and dark, thick or very dirty oil may need diluting before a count, so we confirm in writing whether the counter suits your oil before it is booked.
Who takes the samples and runs the counter?
The quotation states it. On our own flushing and filtration jobs, our site team takes the bottle samples and counts them.
Is there a price list?
No. Every counter rental is quoted on its own, and our written terms set out the charge, its basis, the rental period and any other costs, such as transport.
Does an enquiry book the counter?
No. We first confirm in writing that the counter suits your oil and is available on your dates; the booking follows your order.
Do you rent it to plants outside Chennai?
Give the plant’s location in your enquiry, and the quotation for that site sets out the transport.
Can you count our samples for us instead?
Yes. Our oil analysis service counts particles at your site, and we have quoted NAS tests per sample for oil sent to us.
Check Suitability and Availability
This sends a request; it does not book the counter. We confirm suitability and availability in writing.
Request received. Your reference is {ref}. We reply during office hours, Monday to Saturday, 9.00 am to 5.30 pm. For a breakdown or a plant shutdown, call +91 99400 49505 at any time. Nothing is booked or ordered until we confirm scope, availability and terms in writing.Prefer to talk? Call +91 99400 49505 or WhatsApp us.
