Shields are the basic ball bearing closures. They protect the bearing from large particle contamination and also help retain lubricant. The shield does not contact the inner ring and protection is afforded by the close running tolerances between the i.d. of the shield and the inner ring step.
Shields are available in carbon and stainless steel. Additionally, some bearings can be manufactured with removable shields to facilitate periodic relubrication.
(Check with the Schatz Engineering department for the availability of removable shields.)
Seals are a positive contacting closure that protects the bearing from contamination and provide an excellent retention of grease. The are numerous materials and designs available for bearing seal options.
The following is a list of the standard Schatz sealing designs:
Buna N molded rubber lip seal – The rubber lip seal provides excellent protection due to the face contacting seal. The seal is available as a molded seal with a steel insert, or as steel shrouded with Buna N inserts. The operating temperature range of these seals is -65º F to 225º F.
PTFE Lip seals – These seals provide a wider operating temperature range than the rubber seal (maximum operating temperature of 550º F). Additionally, the PTFE contact results in lower starting torque, therefore these seals can be used in applications where torque sensitivity is a consideration. Most designs incorporate a steel retaining ring to support the PTFE disk. Some designs are removable.
Special Seals – Schatz has designed many special seals to accommodate the needs of difficult applications. Seals are available that are designed for use in high temperatures, high operating speeds, low starting torque, or that are designed to operate in environments of extreme contamination. Please consult the Schatz Engineering department for further information on seal designs.