Hi guys, new to lubrication with a ton of questions. I read an artical today from Trico Corp. that mentioned avoiding the use of galvanized containers due to additives in some lubricants that may have a reaction with the zinc plating, causing it to form metal soaps. While I'm sure this applies to pluming as well, my question is: Does anyone have more information on which additives have this reaction and which lubricants use these additives or where I can find this information?

Thanks for your time and comments

JDW, we avoid using galvanised pipes and fittings due to the flacking off of the galvanising. This may occur from a chemical reaction or flow related issues. Our plant uses stainless steel for lubrication systems. I'm sure there is galvanised pipes still in our water circuits that are not on critical pieces of equipment.
To maintain clean fluids I would avoid the galvanised style pipes. There are some times where they can be used so long as you are aware that the fluid may have small particle of contamination.

I hope this is of some help.

Hooch

Thanks for the post Hooch I appreciate any info on the subject. We also use stainless for most plumbing however I have noticed some galvinized fittings, not many but still, after reading that artticle about the chemical reaction it just made me wonder what other information might be out there. We have a problem child (Hydrualic pack) that is clogging the suctioin filter(strainer) and starving the pump until we replace it. This is for some reason occuring approximatly every 2 weeks. There is also a good amount of water getting into this system and just has me stumped. It does sit in a warm and hummid environment but has no direct water spray either. Desicant filter looks way to good for the amount of water showing up on the report. This Pack runs a small saw. Is it the water issue cloging these strainers? I'm told this has been an issue for quite some time. Like I said, I'm still very wet behind the ears when it comes to oil. Any input is valued. Thanks Again.

A quick comment about the chemistry of galvanized steel. It is a zinc coating that is applied or electroplated to the steel. Zinc is more anodic than iron, so the zinc corodes preferentially to the iron (you may have heard of zinc being used as "sacrificial anode"). Also creates an oxide layer which helps protect the underlying metal but is not necessarily tightly adherent. Galvanized nails have a greyish/white appearance which is the zinc oxide / zinc carbonate products of oxidation.

One big thing to watch out for with galvanized steel is mixing them with regular steel. If part of your pipe in contact with solution is regular steel and part is galvanized steel, then you will have accelerated corrosion of the zinc. Worst case is large amount of regular steel in contact with solution and very small galvanized steel (like fitting) in contact with the fluid, provides a large cathode area which forces a lot of current through small anode area and will corrode the galvanized VERY quickly. I don't know whether the same concern applies to mixing galvanized with stainless.

One more related item - if you use galvanized fittings for transformer oil sample connectiosn you can see falsely-high H2 gas results. H2 gas is another one of the corrosion products.

We have certainly seen a lot of the particulate cartridge filters fill up very quickly when you have a system with a lot of water. We usually try to bring in some other kind of approach for removing water (Pall skid or feed/bleed etc) when the water concentration is high.

JDW,sounds to me that you need to change those fittings. Useing a brass or stainless option may be the key to resolving your issues. Another option is to put a magnetic plug in the tank and see what comes of this.
Have you considered getting the filter/strainer pulled apart by a failure investigation team? This would be a good start as they cut the filter apart and work out for you why it failed. They can usually carry out a chemical analysis as well on the material etc. We use a company called Bureau Veritas here in Australia they have a pretty good investigation team. I'm sure they would have a similar setup in the USA.
As for water contaminating your hydraulic system, I would be looking at the way they clean around this machine. Does it get hosed out to remove material build up? If so, you may be introducing water through the inspection port on the tank etc.

One last thing I would be doing is to take regular oil sample's. This way you can get some trending and you can also ask the important questions like what has changed since the last survey to get the contamination levels. This may need to be done every couple of days until you can determine the problem. This may sound excessive but for the cost of the sample analysis it may be an easy way of determining what, when and how this machine condition changes. Ask your lubrication supplier for help if your not sure.

One thing I have found over the years is people tend to blame the lubrication or specifications of the system.
When you stand back and have a look at how things are done i.e maintenance and cleaning etc. You usually find the source staring you in the face.Don't be frightened of asking the questions and just observing from a distance. you may be very supprised in what you find.

I hope this is of some help.

Hooch

Excelent info Electricpete, I have a WO in to get these fittings replaced.
Hooch, going to use your advise as well and send in the filters for some further analysis. I had a filter buggy put on to help with the water issue and cleaned it right up, however still have not found the entry point.

One more thing I failed to mention was that this hydrualic fluid is food grade, I dont know if this changes anything but thought I'd put it out there.
I'll leave another post regarding any new info.

Thanks Again
JDWalker

Not to sure if the Food grade does make a difference. If there is contamination in any system it should be removed as best you can. The filter buggy you mentioned may be good for removing particles such as galvanised iron etc but may be useless against water contamination. A water seperator may be a better alternative. You may be able to hire one if you don't already own one.
I'm sure the filter buggy that we use will only pull out a minimal amount of water contamination.
You may wish to also try Ultrasonic leak detection. This technique is used to find pressure and vacuum style leaks, you will find more information in the ultrasound area on this forum or alternatively you can search for UE Systems or SDT on the internet.

hope this helps,

Hooch

Hey all, Sorry for the delay in reporting back on this issue. We did finally locate were our water ingress was coming from. It was acctually multiple problems (imagine that). First of all, what was pluging the return and suction filters. After the filter analysis had identified it was grease in the system, we knew of only one place this could be coming from even though it made no sense, the saw head. after replacing the orings in the saw head we continued to have water/grease ingreasion that still proved fatal to our oil and filters. Again we looked deeper into the saw and found another seal separating the saws hydraulic motor from the saw head. Once we had taken it apart it was pretty clear we found what we were looking for as a milky fluid rolled out after removing 3 bolts. This $30 seal was the cause of replacing hundreds of gallons of oil, downtime, and the source of a few months of my own personal frustrations(July-Nov). Not only was this the source of the grease ingress, but after replacement we also noticed the water ingress had also stopped. We have not had to drain, flush, or refill this pack since Nov. and have only had a few filter replacements as the oil has mantained a satifactory condition. Thanks to all for your input.