Page 219 - Boiler_Operators_Handbook,_Second_Edition

204 Boiler Operator’s Handbook

of oil around the vent you can try putting an extension ery effort to ensure the equipment isn’t overloaded, or
pipe on it, raising the vent at least three or four feet. abused, so the oil can last longer.
If you would like a more engineered design you can Replacing organic oils with synthetic ones can
calculate the change in volume of the air and oil in the reduce wear and power requirements for equipment. In
system then put on enough pipe to provide that volume. addition, the synthetics last much longer than the organ-
Overhead clearances may prevent extending the pipe at ic oils. There are balancing factors in the additional cost
its connection size but that doesn’t prohibit you from of the synthetic oil and reduced power and maintenance
adding a couple of reducers and larger pipe to the exten- costs. If you’re changing large volumes of oil in equip-
sion to get the volume. The concept of this solution is to ment on a regular basis (less than annually) a hard look
create a vertical settling space where the oil that would at synthetic replacements is recommended.
normally settle on something outside the vent settles in Oil lubrication systems require maintenance of
the piping to leave a volume of air substantially free of more than the oil. Filters have to be changed along with
oil to flow out of the vent. the oil and more frequently in some systems. Coolers
A simpler solution is to carry a rag with you and need to be cleaned on the water side to prevent fouling
keep the area around the vent clean; observation of and maintain heat transfer. Temperature controls must
the oil around that vent can give you an indication of a be checked to ensure they’re operating properly and
change in the condition of the oil in the equipment so it maintaining the right temperatures. Centrifugal sepa-
may be a better way. rators and the like have to be maintained according to
Oil has to be changed in any system that doesn’t manufacturer’s instructions.
have its own conditioning equipment just like your car. Anything that affects the temperature of a lubricat-
Also, just like your car, there are rules of thumb that ing system is critical to continued safe and reliable op-
are wasteful. Most cars don’t need an oil change every eration. If a lubricant gets too hot it will break down and
3,000 miles but that rule of thumb is treated as inviolate. lose its lubricating properties to allow metal surfaces
I change oil in my car every 7,500 miles unless I happen in the equipment to rub, gall, and scrape with failure
to do some driving on dirt roads or in similar dusty con- occurring rapidly. That’s why you’re told to log an oil
ditions when I think it prudent to change the oil right temperature that is always the same. The purpose is to
after that situation. No, it’s not my idea, that’s what the notice when it suddenly does change so something can
instruction manual says to do. be done about it.
The instruction manual for the equipment will Cleanliness is the next important factor because
provide some guidance but you can judge the need for clearances in bearings and gears are so small that a par-
an oil change yourself by noting the condition of the ticle of dust that’s almost invisible in the air can span
oil. You don’t have to be a tribologist to tell that the oil the clearance to produce damage in the equipment. Any
needs changing more frequently when you see distinct opening into a lubricating system should be fitted with
changes in color or particles in the oil before it’s due to a filter and systems should not be opened unless provi-
be changed. A problem with water supply to the cooling sions have been taken to prevent dust and dirt getting
system that resulted in a significant rise in oil tempera- into them. A little contamination of a lubricating system
ture should be followed immediately by an oil change or can result in total system failure costing thousand times
testing to see if it needs changing. more than the oil.
Other indications include presence of a whitish
waxy substance that indicates water has contaminated
the oil. The opposite isn’t necessarily true however; just INSULATION
because the oil looks good you can’t be assured that
it’s okay. If the cost of the oil and labor to replace it is Insulation is one of those items that, for whatever
not significant (less than $100 per year) then you might reason, never gets the attention it deserves. It’s not un-
as well change it according to manufacturer’s recom- common for me to be called to a plant for complaints of
mendations. If the cost is significant you should employ high fuel bills only to find that half the insulation has
the services of a tribology lab to test the oil and make fallen off. You’ll recall the story about rain load in the
recommendations for changing it. I know of systems section on knowing your load; that was because of lack
that have operated 100,000 hours without an oil change. of adequate insulation. Burning fuel unnecessarily be-
A manufacturer’s recommendations are normally based cause the insulation isn’t maintained is not what a wise
on the most severe use and the wise operator makes ev- operator does.