Steam oil

[gwrdriver]

The assertion that to emulsify with steam a steam oil must have tallow is incorrect. See Tristan's post above. And my experience with 460 (or thereabouts) oil is, like Bill, it's works just fine in both types of lubricators.

[Glenn Brooks]

I bought a 5 gal bucket of tallow based steam oil (from Chevron i think] in 1995. Still using it. Doesn’t go bad in storage, doesn’t separate, doesn’t emulsify in the container, and doesn’t turn rancid after use. Near as I can tell, it’s very long lasting and does an excellent job.

Glenn

[Cary Stewart]

Bill Donovan at Real Trains sold different steam oil for displacement and mechanical lubrication. He explained it to me a long time ago but I have forgotten why the difference. Stuart-Turner's stationary models all used displacement lubricators attached to the engine at the steam inlet. Most locos that I have seen have mechanical lubricators. Bill, if you are lurking please tell us the difference.
Cary

[Bill Shields]

Displacement lubricators are easy to build, small, are almost infinitely adjustable and work well on a single inlet...

There are lots of large locos that run on displacement lubricators...just look to Europe and the displacement lubricators that Bill van Brocklin championed for decades.

[rspringer]

Thanks for the input.

[James Powell]

I would suggest, as the owner of a somewhat lubrication sensitive 3.5" gauge loco, that a pumped supply is better than a stuart turner style displacement lubricator. The more complicated hydraulic driven displacement style are probably co-equal with a pumped lubricator.

The type of steam oil can matter- I have some Gulf 1200w and a bucket of Chevron TK460W, which is 600w. It's night and day with Caribou, it seizes up with the 600w, and is fine with the heavyweight oil. This is with a superheated boiler- you are OK if you keep the water level well up and use the TK460, but heaven help you if you try really hard with it. (like 3 passengers & determined driver type of hard trying...). The 1200w is sticky enough to be fine under the same conditions. Lubricator is set to keep the chimney 'sticky' with oil, and it does so with both.

As dad says about Tribology- any oil is better than no oil, right oil is better than any oil, and best is the right oil at the right amount... I'd trust the manufacturer's to get it "right" as to specific properties. I wouldn't trust that they have experts to tell you which is the right oil, with the possible exception of Morris oils in the UK, who still sell enough oil into the steam market to have some understanding of what they are selling to. However, most of the dealers are fairly good at explaining what they have. Chevron TK460 is one of the few major commercial oils that is still available. When I went to buy mine, I had access still to the RCN oil books, including the right oil for the TBA & other up and down pumps, so could see what it was = to, and what the use was IAW the RN and RCN. So I am aware that it is a low temp (200 PSI/saturated) type of oil vs a higher temperature rated oil.

James

[fredrosse]

Steam Cylinder Oil, named compound oil, containing tallow, adheres to surfaces and gives much better cylinder lubrication than pure mineral oils. However it is virtually impossible to separate the emulsion of water and oil, so re-using the condensate water as boiler feed is not a viable option. Oil in boiler feedwater is not good, and has let to many boiler failures.
Almost all automotive oils are "detergent oils", and will also form an unbreakable emulsion with water.

Pure mineral oil, real "non detergent" oil, can be used for cylinder lubrication, but much more oil must be used because it washes away from sliding surfaces much more easily than compound steam cylinder oil. This oil can be separated from condensate, and then the condensate can be used for boiler feed. Locomotives and other steam engines with atmospheric exhaust don't re-use condensate, so not an issue in these engines. Steamboats, and other condensing engine services must avoid compound cylinder oils to protect the boiler.

Note that automotive supply houses often sell "non-detergent" oil, however this is a misnomer. This oil is marketed as "non-detergent", but it is almost always detergent oil that has failed some aspect of the specifications for the classification as detergent oil, so it is labeled "non-detergent", and sold cheaply. To get real unadulterated mineral oil, I buy the veterinary mineral oil, which is easily separated from water. It also separates dollars from my wallet quite well.

[Fred_V]

What does oil in boiler feed water do to a boiler to cause failure?

I have used soluble oil in my feedwater during washdown. it worked really well to prevent rust. LSB came along and I quit using the soluble oil.

[Fender]

If it’s not possible to separate the emulsified oil from the water, then how do locos with “open” feedwater heaters, such as Worthington, cope? The exhaust steam definitely mixes with the feedwater.