Paxton blowers are precision engineered to last for years and years. In fact, we frequently hear from customers whose blowers are 20 or even 30 years old, and still operational. However, blower failures do occur, and the causes of failure are explained herein. For each of these conditions, there may be several installations or operational issues contributing to the condition.
Bearing Failure: Bearing failure is a condition which can be considered routine maintenance. The bearings used in Paxton Blowers are ABEC-7 ball bearings using high temperature grease. Over several years of operation, there will be a routine requirement to overhaul the blower head due to common wear of the bearings. However, premature failure of bearings can be caused by over-temperature operating conditions:
- The high temperature grease used in the bearings may liquefy and run out through the shields if extreme temperatures are encountered.
- Drying up of the grease due to high temperature operation may cause carbon build up and failure.
Once lubrication is lost in the bearings, failure will result. Unfortunately, if bearing failure is not discovered in the early stages, the blower will eventually fail catastrophically resulting in down time.
Ingestion of Foreign Matter: The number one cause of failure of a well lubricated bearing is contamination getting into the races of the bearing. This condition results from poor or lack of filtration at the intake of the blower. An air intake filter is always required. Although some fine dust may pass through the blower without damage, a gradual buildup of dust or materials in the blower can result in a coating on the impeller and housing. This will affect the balance of the impeller and rotating assembly and will eventually cause the bearings to overheat, shortening the service life of the blower. The filter that is included with your Paxton blower will normally remove particles to 5 microns in size and will usually eliminate the possibility of ingestion of damaging foreign matter. It is imperative that the user check for inlet filter restriction and ensure filters are maintained in a clean condition. Replacement every three months is usually advised. A pressure differential gauge and/or switch at the blower inlet is beneficial in alerting the user to these conditions before they become critical, and these pressure gauges are included with every PX-series blower.
In addition to particulate and dust contamination, it is important to note that the blower must be protected from ingesting liquid any chemical vapors that could compromise bearing lubrication. If this foreign matter is small enough to get past the seals, can lead to contamination of the bearings causing bearing failures.
Incompatible Environments: When considering a blower for an application, it is also important to consider the environment that the blower will be in. While most industrial environments are acceptable you need to consider the site temperature, air quality (steam / chemicals in the air, airborne debris). Paxton blowers should not be operated in areas having high levels of ozone, as ozone will cause premature belt failure. If high levels of oils, cutting fluids, or syrup are in the operating area, the Paxton blower should be moved to a cleaner area; and the inlet piped to a clean air. Contact Paxton for recommendations.
Operation Outside of the Performance Limits: When considering a blower for an application, the requirements for the application must be within the blower’s design performance capabilities. If the blower is operated at excessive pressures with insufficient air flow passing through it, higher operating temperatures will result. These higher operating temperatures may result in premature bearing failure. The Paxton blower should also be operated with the recommended number of air knives or nozzles attached. The creation of excessive air flow beyond the design parameters such as with the addition of extra air delivery devices or by providing air bleed-off without a throttling valve (i.e. running the system wide open without sufficient air flow resistance), then the motor will over amp and overheat. More air flow comes with a need for more power from the motor.
Another issue is having too much system resistance beyond the design parameters, such as an excessive number of elbows, excessive length of pipe, pipe size with too small of a diameter, and undersized air delivery devices etc. will cause the blower head to overheat, leading to bearing failure, due to excessive churning of the air inside the blower housing with insufficient cooling air flow. Please consult our Engineering Bulletin for piping recommendations.
Paxton Engineers have more than 75 years of combined experience to ensure that they select the most appropriate blower for the application to ensure that you get the maximum life from your Paxton system. Be sure to discuss any environmental conditions with them, as they are specifying the right blower for your application.