Rig Wash Dilution for Pressure Washer: 7-Step Guide

There is no single rig wash dilution for pressure washer use. The correct ratio is the one on the current technical data sheet (TDS) for your exact part number, because pressure-washer makers state that dilution must follow the detergent maker's instructions, and a concentrate and a ready liquid are different formulations.

Once you have that ratio, three things decide whether the oil comes off: reading the ratio the right way round, knowing how much your injector dilutes it again, and keeping the solution wet on the steel until you rinse. The steps below cover drill floors, skids, pumps and pipe racks washed in Muscat, Sohar, Duqm and the interior fields.

Rig wash dilution for pressure washer use starts with the part number

Take your dilution from the TDS for the product in your drum, not from another supplier's sheet or a different rig wash. Dilution instructions belong to each formulation, so a product described as a concentrate should not automatically get the same ratio as a ready liquid.

We supply two products under two part numbers each: Rig Wash Liquid (RXSOL-16-1042-025), the same Rig Wash Liquid under code RXSOL-16-1042-210, and Rig Wash Liquid Concentrate (RXSOL-16-1014-025) with its RXSOL-16-1014-210 code. Ask us for the current TDS and SDS for the code you order, and keep a copy with the wash crew.

How to read 1:10 and mix a 20-litre batch

Write every ratio as product:water. Read that way, 1:10 means one part rig wash plus ten parts water by volume, which gives 11 parts in total.

That mix holds about 9.09% product by volume. A 10% solution, where the product makes up a tenth of the finished volume, is slightly stronger, so check which convention your TDS uses before you mix.

For a finished batch, divide the batch volume by the total number of parts. For a 20-litre batch at 1:10:

• Product: 20 / (1 + 10) = 1.818 litres
• Water: 20 - 1.818 = 18.182 litres
• A 10% solution of the same 20 litres would need 2 litres of product and 18 litres of water.

The 1:10 figure only shows the arithmetic. Put your own TDS ratio into the same formula and measure with a graduated jug rather than by eye.

Does the pressure washer injector dilute rig wash again?

Yes. A downstream injector mixes the solution it picks up with more water, so the concentration that reaches the steel is lower than the mix in your container.

The applied concentration is the pickup concentration x the detergent solution used / the total spray collected. Siphon rate also changes with the temperature and viscosity of the solution, so a reading taken on a cool morning may differ from one taken at midday.

Measure your own machine with a clean-water draw test:

1. Fill the pickup container with clean water to a marked level.
2. Run the washer in detergent mode into a bucket of known volume for a timed period.
3. Record how much water left the pickup container and how much spray you collected.
4. Work out the applied concentration with the formula above.

Example: your pickup mix is 9.09% and the container drops by 1 litre while you collect 10 litres of spray. The applied concentration is 9.09 x 1 / 10, about 0.91%. Check whether your TDS ratio refers to the solution in the container or the solution on the surface, then adjust the pickup mix or injector setting to match.

Step-by-step: pressure washing oily rig equipment

Follow these seven steps in order: set up containment, protect the crew, mix, test, apply, allow contact time, then rinse and flush.

1. Set up the wash area. Wash on an impermeable pad with drainage to containers, a sump or a treatment system. Where the equipment cannot reach a wash bay, lay a mobile wash mat to collect the water.
2. Protect the crew and cool the steel. Wear the PPE named in the SDS, including eye, hand and foot protection, because the spray can throw particles. Never point the jet at anyone: pressure-washer spray can cause injection injuries. Let equipment cool before washing, because detergent on hot surfaces can dry and damage them.
3. Mix the batch. Use the TDS ratio for your part number and the product:water calculation above. The published safety sheet for the concentrate calls for goggles, avoiding eye contact and keeping the container tightly closed; confirm this against the SDS that comes with your delivery.
4. Spot-test the surface. Apply the solution to a small area of painted metal, aluminium, rubber or seal material, rinse thoroughly and check for any adverse reaction. Temperature, pressure and concentration all need to suit the surface you are cleaning.
5. Apply at low pressure. Downstream detergent systems put the solution on at low pressure. Work in sections small enough to keep wet.
6. Allow contact time and agitate. Leave the solution on for the contact time on your TDS. For reference, one pressure-washer maker gives 1 to 5 minutes for its detergents, which is an equipment example and not a rig wash specification. Brush stubborn grease before rinsing, and if the solution starts to dry, wet the surface with fresh water.
7. Rinse, inspect and flush. Switch to a suitable high-pressure rinse nozzle and rinse thoroughly. Hot water carries a scalding hazard. Inspect for oily film before signing off, then flush the detergent injection system with clean water as the equipment manual describes.

Why oily residue remains and how to fix it

Oily residue after rinsing usually means the cleaning balance is off, not that the washer lacks pressure. The sections below cover the most common causes on Oman sites.

Oily film after rinsing

Residual oil points to the wrong balance of detergent type or concentration, contact time, temperature and mechanical action. Pressure alone does not decide the result.

Run the draw test to confirm the nozzle concentration, give the full contact time and brush the worst areas. Hot water helps loosen oil and grease and can reduce the amount of detergent you need.

Solution drying in Muscat heat

Summer sun on a skid or pipe rack in Muscat or Duqm can dry the solution before the contact time ends. Wash early in the day or in shade, cool the steel first and work one manageable section at a time.

Keep a hose of fresh water ready to rewet any section that starts to dry, and make sure enough rinse water is on site before you begin.

Hard or soft water

Some rig wash formulations work in either hard or soft water, but this depends on the formulation. Tell us your water source when you order, and check the TDS for your part number.

Collecting oily wash water in Oman

Equipment wash water can carry oil, grease, sediment, metals and cleaning chemicals, so drain it to containers, a sump or treatment. If your wash bay feeds an oil-water separator, choose a quick-break degreaser and monitor the separator output.

In Oman, discharging or reusing treated wastewater needs an Environment Authority licence, and the collection, transport, treatment and disposal of hazardous waste falls under its waste-management licensing. Collecting the water does not give you permission to discharge it.

Where to buy rig wash in Muscat and across Oman

We supply Rig Wash Liquid and Rig Wash Liquid Concentrate from our warehouse in Barka Industrial Area and deliver to sites in Muscat, Sohar, Salalah and Duqm. For yards near the port, the same concentrate is also listed on Sohar Chemical for Sohar port deliveries, and on Oman Chem for interior field sites.

When you request a quote, send the equipment material, the type of soil, how your washer applies detergent and the volume you need. We reply with the right part number and the current TDS and SDS.

Muscat Chemical (Muscat & Barka for Business Trading), Barka Industrial Area, Sultanate of Oman. Phone +968 77333599, email muscatchem@gmail.com.

Request a quote on WhatsApp: +968 77333599.

Frequently asked questions

What dilution of rig wash should I use in a pressure washer?

Use the ratio on the current TDS for your exact part number. There is no universal dilution for rig wash, and Rig Wash Liquid and Rig Wash Liquid Concentrate are different formulations. After mixing, check how much your injector dilutes the solution again at the nozzle.

Does 1:10 mean one part rig wash to ten parts water?

Yes, when the ratio is written as product:water. That gives 11 parts in total, or about 9.09% product by volume. A 20-litre batch at 1:10 needs 1.818 litres of product and 18.182 litres of water.

Does a pressure washer injector dilute the detergent again?

Yes. A downstream injector mixes the solution it picks up with more water. The applied concentration is the pickup concentration x the solution used / the total spray collected, which you can measure with a clean-water draw test.

How long should rig wash stay on oily equipment before rinsing?

Use the contact time on the TDS for your product. One pressure-washer maker gives 1 to 5 minutes for its detergents as an equipment example. Never let the solution dry: wet the surface with fresh water if it starts to.

Can rig wash be used with hot water or hard water?

Hot water helps loosen oil and grease and can reduce the amount of detergent you need, but it carries a scalding hazard. Whether a rig wash works in hard or soft water depends on the formulation, so check the TDS for your part number.