| MadSci Network: Chemistry |
Michael, your question might better be answered by the manufacturer of the equipment that you currently use. But here is a brief explanation of your question.
A multiviscosity oil is "made" the same way as a single viscosity oil, but the multiviscosity oil is able to tolerate a wider range of temperatures. For example, a 30 weight oil is able to properly do its job down to a certain temperature, say 30 degrees Fahrenheit, whereas a 10W40 oil is able to do its job in a wider range, say 10 to 40 degrees Fahrenheit. The reason you would want to use a single viscosity oil would be if the engine runs constantly and you do not need to worry about cold oil and the possiblility of it getting so thick that it won't flow. If the piece of equipment is on used on and off, and you are in a cooler climate zone or in the winter, there is the possibility that the oil temperature will cool quite a bit before it is needed again. In this case a single viscosity oil is not recommended because of the need for it to flow and lubricate at both high and low tempertures. I hope this helps.
Carlin Gregory, Williams Gas Pipelines-Texas Gas
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