Protecting Your Airend is Our Business

Schedule a Bearing Test and get a FREE Hunting Hat*

John Henry Foster (JHF) is very aware of the competitive environment in which all businesses operate today. We realize that it’s of utmost importance to maximize your investment in plant operations, especially in equipment vital to production, such as the rotary screw air compressor. The rotary screw compressor is essential to the production of virtually all products and since most production equipment utilizes compressed air in some fashion, controlling downtime and efficiency of the air compressor is of primary importance. The main component of the rotary screw air compressor is the compression chamber, commonly referred to as the airend. The airend contains gears and seals, as well as rotors which are supported by bearings, and the failure of any of these components can have a catastrophic effect.


An airend before complete overhaul (lots of wear and tear).

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You want the rotors free from touching any part of the compressor. A Bearing Test will be able to tell you if there is unnecessary vibration.


AirEnd Programs

To help ensure reliability and optimal performance, JHF has incorporated two programs as an integral part of its service capabilities – airend monitoring and airend rebuilding. AIREND MONITORING The airend monitoring program consists of monitoring and tracking of the airend status. Our capabilities allow us to gauge the condition of the bearings and other critical components in order to predict failure. Predictive monitoring also allows us to analyze the condition of the airend to allow time for scheduled repair, thereby reducing costs and lost productivity. AIREND REBUILDING In the event of a failure, the airend rebuilding program offers quality rebuild capabilities unmatched in the industry. The rebuild results in an economical alternative to factory exchange or a new airend. During the rebuilding process, airends are completely disassembled with all seals, bearings and O-rings replaced. Repairing damaged rotors, rebuilding oil pumps, metalizing the shafts and other internal repairs are performed as necessary. All components are then reassembled, clearances are checked, and airends are spun to a final check. Our factory-trained service technicians have over 100 years of combined service training and a proven track record of successfully performing over 1,000 rebuilds making us uniquely qualified to repair and recondition airend units.

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The body of an airend is extremely difficult to open unless you have the proper tools which JHF has in-house

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Once the airend is opened, the gaskets, bearings, o-rings, rotors and seals are removed and diagnosed. If these parts are removed or inserted incorrectly, the machine will not operate.

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Once the parts are removed and diagnosed, they are cared for and cleaned. Any sign of wear and tear that will harm your machine, and new parts are ordered from JHF’s parts department.

For more information regarding your rotary screw air compressor and how our airend monitoring and rebuild capabilities might benefit you, contact our Service Department at, 651.452.8452 or download our airend flyer.




To schedule your Bearing Test* and reduce overall operational costs and to get your FREE JHF lucky hunting hat, please fill out the form below. *The customer pays for the Bearing Test. IMG953568



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Contact Us

651-452-8452 | 800-582-5162


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