| Want to be a sponsor? |
|
| Our Web Page |
Check us out! | |
| Welcome to the Centrifugal Blower Maintenance Minute,
the 60 second newsletter designed specifically for centrifugal air & gas blower operators. Each month we will feature a different aspect of service and maintenance to centrifugal blowers. We will review operation, troubleshooting, actual case histories, and answer reader questions. |
|
| Oil leaks --- Why?
 The most common complaint in the operation of multi-stage centrifugal blowers is oil leaks, especially of new equipment. It doesn't matter which brand, they all have oil lubricated blowers that leak oil. The oil mist system they use is designed to put oil in the air so it can keep the bearing lubricated. It has proven extremely difficult to keep that oil laden air contained within the bearing housing. Closed loop oil systems have greatly reduced the "overspray", but nothing that I know of has totally eliminated the leaking. The standard system with the breather cap on top allows the oil spray to "vent to atmosphere", but the oil usually seeps down the side of the housing onto the floor. Or it can be drawn onto the face of the drive end housing by the air flow created by the coupling spinning. The oil laden air also easily leaks by the bronze laby seal at the back of the bearing housing. From here it "sticks" to the housing and then drips from the lowest point-the oil plug. Incorporating an In-Pro seal to replace the laby seal in the back of the housing, helps to reduce this leakage, but the extra cost can make it prohibitive.
To prevent new machines from leaking oil, the only fixes that have had any success for me are replacing the breather with a plug, adding an o-ring to the shaft between the housing and the laby seal, adding an RTV ring around the shaft at the drive end where the shaft goes thru the cover, and changing to a thicker, heavier oil(SAE 50).
 However, the most common cause of oil leaks still tends to be overfilling! It seems so simple to just keep oil in the globe, or to the line on the sight glass, but people always tend to keep more oil in the housings than they are designed to hold. When I receive calls for oil leaks, my first recommendation is to change the oil, being sure to use the manufactures' recommended oil, clean the outside of the housing real good so you can see clearly where the oil is leaking from, and call me in a week or so. At least half of the time, they call back to say "the leak is gone"!!
My recommendation to prevent oil leaks is to purchase grease lubricated machines. Since most of the larger bearing machines don't have grease lube as an option, expect to have oil spots on the floor. The technology is out there to manufacture oil free machines, but it costs! As we move further into our "eco-friendly" society, it is only a matter of time before customers insist manufacturer's provide oil lubricated blowers that do not leak!
© Copyright 2009 Snyder Technical Services, LLC. All Rights Reserved
|
|
|
|
|
Maintenance Minute is published each month by Snyder Technical Services, LLC and is based on the work of former Lamson National Service Manager, Bill Snyder. Should you have any questions, or problems to discuss, please contact me.
Bill Snyder
Founder - Snyder Technical Services, LLC |
| Next Month:
Not enough flow --- Why?? |
Thought for Today:
"Man's mind, once stretched by a new idea, never regains it's original dimensions!"
---Oliver Wendall Holmes
| |
|
