Synthetic Oil and Drain Frequency

A PAO based mineral (the most commonly used) oil chemicaly is very similar to a mineral oil and is generally fully compatable (check with your lubricant supplier). You only need to drain your system flush with a small amount of the synthetic oil to get most of the mineral oil out and refill with your synthetic.

Oil analysis gets a bit more complicated but is easily handled. You need to decide whether your facility size and expected sample load would justify onsite analysis. Several small labs are available which will screen your samples (we use the CSI 5200). You will also need an ofsite labe for tests that are not practicle to do onsite.

There are a number of manufacturers of portable filtration units or you can build your own. If your equipment is all laid out at floor level with wide passageways then a filter cart works well. If you have alot of remote gearsets that are on elevated platforms modular portability is important. I have a lot of conveyor heads and tank agitators that require getting the unit "up there". If your filter cart weighs 150-200 pounds it is difficult to get it where it will do the most good. So a pump, filter, hoses, and electrical cord or air hoses all in seperate pieces that can be handlined up to your gearset is a better option. You can email me directly for more discussion.

Dear Joy

First than all, you need pay attention to each rotating machine you have in your Plant. For example, if you have Steam or Gas Turbines (Generators or Centrifugal Compressors), you must to follow the ASTM D-4378-03 Normative, in order to have a guide about the oil analysis and drain intervals. In the other hand if you have Screw Compressors, or Hydraulic Systems or Gears, the typical package for oil analysis is a little different. But the main tests are, Viscosity, TAN, Water Content (KF), ISO 4406, Color, Metals.

In reference to the Compatibility issue, you should extract all the mineral oil, before refill with Synthetic, and if possible, perform an oil flushing, in order to retire all the mineral oil. You could have problems with compatibility between the two oils (foam, sludge, etc.) and between the synthetic oil and some parts of the machine (seals for example).

At last, for the portable filters, the key point is the Beta Ratio of the filters. It is good to have Beta 6 > 75 or better.

I hope these comments helps you. I am sorry for my English (it is not the best).

Regards,

It is virtually impossible to remove all mineral oil from you system prior to introducing a synthetic. A group IV Polyalpha olefin (PAO) synthetic base stock is fully compatable with mineral oils. Incompatability may arise in componants of the additive package and your lubricant supplier should be consulted on possible conflicts. You could do some testing of different mix ratios to determine if the oils will cause problems if mixed. Generally if you stay with the same oils typicaly used in various industrial applications (turbine oil for turbine oil, and gear oil for gear oil formulations) you shouldn't encounter problems but, still procede with caution and see if your supplier will warrantee compatability.

Joy

Just to share my experience in changing over to PAO compressor oils from mineral oils, we had drained the mineral oil but since 10 % of the oil remains in the system,we had flushed with fresh synthetic oil ( Min Level) and removed the same ,which was used for top up purposes.

Then we had charged fresh synthetic oil to avoid compatability issues. We could extended drain periods by seven times. This helps for initial changeover from mineral to synthetic.

We had monitored TAN and Insolubles for extending drain intervals.

More information on this issue is welcome.