Use of Mechanical filtration unit

You have probably picked one of the more easier cross-contamination concers, given the traditionally low additive levels contained within a hydraulic oil. General rule is 3 times the flush, but that is conservative but probably needed when you start looking at transformer oils. I would recommend that 3 flushes with the transformer oil that you intend to filter and dump that oil appropriately. You can calculate the dilution rate of your efforts to get to best possible worst case scenario but understanding the overall volume capacity within your cleaning unit, residual volume (say 10% whence you drain it), then x3 goes ....

Hello Srini,
I'd be very concerned about introducing a non-transformer oil into a transformer (especially a napathinic base). For that reason the idea of using the same system back and forth should be discouraged. Secondly in a general way the things that we want to remove from a transformer will not normally be removed with simple mechanical filtration. Generally transformer oil is said to be conditioned not filtered. Primarly the removal of water is more importand to the life of the transformers than the very small amount of disolved metals. With large amounts of metals ( as filterable with a hyd filter cart system) in the transformer oil, I'd stand way back from that equipment if the power was flowing. Transformer oil and gass analysis is expensive but it will show you what the oil condition is and what is required to bring the fluid back to a servicable condition.
regards.....

Hello Allen,

I intned to use a single cleaning machine to oil. The company I am associated with offers commercial oil cleaning solution. Hence the question. I would like to have minimum number of machines to clean these oil and hence the question.

I'm with Alan Wallace on this one. You do not want to be the guy who contaminated someone's transformer oil while attempting to recondition it. The flushing procedure you will need to perform to switch between those two product types will need to be very extensive. If you run the numbers, the capital cost of having another unit may be less costly than the ongoing expense of frequent, very comprehensive flushes.

Bad oil in a hydraulic system = a cratered pump, not good, but a problem of limited scope and low visibility.

Bad oil in a transformer = large metal can full of oil on fire on top of a utility pole.

Forced to choose, I'd rather be the guy who caused the former problem.

quote:

Originally posted by Lamont B Dumont:
I'm with Alan Wallace on this one. You do not want to be the guy who contaminated someone's transformer oil while attempting to recondition it. The flushing procedure you will need to perform to switch between those two product types will need to be very extensive. If you run the numbers, the capital cost of having another unit may be less costly than the ongoing expense of frequent, very comprehensive flushes.

Bad oil in a hydraulic system = a cratered pump, not good, but a problem of limited scope and low visibility.

Bad oil in a transformer = large metal can full of oil on fire on top of a utility pole.

Forced to choose, I'd rather be the guy who caused the former problem.

I want to see the pole that can carry my 500,000 volt 3 phase transformers.

Nevermind the very real concern of multi-year lead times for replacements.

Do you realise that many oil companies now use the same base oil for both premium hydraulic and transformer oils? Napthenics vs. Parrafinic - Gas absorbing vs. Gas evolving, old school.

Do you realise that hydraulic oils typically use around 1% in additives? When have you last looked at a used oil analysis to see the ppb results for metals from a transformer oil sample? There are always low levels of metals that are sourced from a variety of sources in a used oil analysis report from used transformer oils....

Wow, you should see how some of your bulk food products are transported by the same tankers that move non-food products like diesel and petrol, there are flushing procedures and testing required before handling different products in bulk containers - are you aware of this or do you think that there are dedicated one-way transport facilities used around the country?

As a guy who ran the lab at a base-oil-&-chemicals terminal for 8 years, I'll note a few things:

While they may just look like a bunch of 80,000 lb barrels rolling along on their sides at 65 mph, the configurations of liquid bulk trailers differ significantly, depending on their service. I'm not aware of the practice of cross-loading food-grade and non-food grade products. I am aware that loading the physical configuration of certain food-grade trailers with petroleum products will get you an NOV (notice of violation) from some state DOTs.

I've also been behind any number of trailers hauling tallow for industrial use (like cutting oils) that have "NOT FOR FOOD USE" in large block letters across the back and near the dome covers.

So yes, I do believe there is a regulatory line between food-grade and nonfood-grade products, based on personal experience with such requirements. Do I suspect that some folks cross that line? Sure, but they are risking fines in some places. I know, because shortly before I arrived, the terminal had just revised the pre-load inspection procedure to prevent a recurrance of just such an event. Are the rules different in Australia than in the US? For your sake, I hope not.

As for dedicated transports, they also exist, especially for high-volume, contamination-sensitive products like transformer oils. Such trailers are generally one-holers with desiccant breathers and bottom sampling ports.

There are also a lot of dedicated plasticizer (diester) trailers. If a truck owner can avoid a roughly $150 clean-out fee, they will. So, large transport companies work that aspect pretty hard.

Are transformer oils moving toward paraffinics? Perhaps, I've been away from that part of the business for about 7 years. If it's happening, it's because of supply. Naphthenic oils have certain advantages that are a function of their chemcial structure.

About a decade ago, a certain US Gulf-Coast naphthenic supplier converted that capability to Grp III parafinnic production and the market lost a good chunk of of some of the very best transformer oil feedstock with possibly the best negative gassing tendency of any oil available. So, there is probably some efforts afoot to use parafinnics in transformer applications. Given the naphthenic supply situation, these efforts are likely made from necessity rather than choice. Since most of the world's naphthenic supply is found in and around the Gulf of Mexico, this transistion is probably further along in your neck of the woods than in mine.

Am I aware that hydraulic oils have about a 1% treat-rate? Sort of - I'm more aware that turbine and non-AW hydraulic oils have about a 1% treat-rate, while AW hydraulics are more in the 1-2% range. In ther absence of popular demand, I won't review treat rates and composition of the various types of fire-resistant, environmentally-friendly, high-VI and the rest of the spectrum of hydraulic fluids.

As for the example of the pole transformer (Type II application) rather than a sub-station transformer (Type I application), that was a conceit intended to put it in terms most folks understand.

quote:

Originally posted by Lamont B Dumont:
...As for the example of the pole transformer (Type II application) rather than a sub-station transformer (Type I application), that was a conceit intended to put it in terms most folks understand.

I knew that.....