Closures - Bearings - Technical
Bearing Closures (Seals / Shields)
Seals and shields are situated between the inner and outer rings of the bearing. The purpose of seals and shields are to protect the inside of the bearing from contaminants and to help prevent the leakage of lubricant from the bearing.
Shields are made from steel or stainless steel. Shields do not contact the inner ring of the bearing and therefore do not increase the running torque. Shields can be either crimped into the inside of the outer race (type ZZ) or held in the outer race by circlips (type ZZS). The ZZS type are removable to allow inspection and maintenance of the bearing. RMB Filmoseal is a type of shield which utilises a film of lubricant between the inner race and the specially designed shield to more effectively exclude contaminants.
Seals are usually made from nitrile which come in contact (type 2RS) or non-contact (type 2RU). Contact type seals which are secured within the outer race and contact the inner race greatly increase start up and running torque, thereby reducing running speed. They also provide a very effective method of excluding contaminants and retaining the bearing lubricant. Non contact seals have minimal contact with the inner race. They provide very effective sealing whilst allowing the bearings to operate at higher speed than contact sealed types. Standard Nitrile seals have a maximum recommended temperature of 100o Celsius (212o fahrenheit). Some bearings are also available with PTFE seals (type TTS) offering very effective sealing whilst minimising torque. PTFE seals can operate at temperatures up to 300o Celsius (572o fahrenheit). Note however that whilst the seals can withstand these temperatures the bearing itself will need special treatment if it is to be used at any temperature greater than those shown in our materials section. For special orders, Viton seals may also be available (temperatures up to 230o Celsius (446o fahrenheit).
Viton seals may also be available for special orders. Viton seals can withstand temperatures up to 230o Celsius (446o fahrenheit). Viton seals are usually used with Stainless Steel bearings and a high temperature grease (such as Mobiltemp SHC32 100) to ensure maximum performance. However, the temperature range of the viton seal extends well beyond the recommended temperature range of the Stainless Steel bearing material, so operating temperature will be restricted to that of the bearing material.
You can find many types of bearings in the Miniature Bearings Australia Bearings Online Catalogue pages.For a huge range of bearings online please visit the Bearing Shop Online Website.
The Small Parts and Bearings has a much larger range of engineering supplies.
Hobby and Engineering Supplies lists a smaller range of products and only the most popular items in each range. They also list many additional hobby specific categories.
Extra information for Technical - Bearings
Registered Australian Company: Miniature Bearings Australia Pty Ltd (ABN 94 069 113 800)
Miniature Bearings Australia offers 125359 products in 2291 categories including ball bearings, thrust bearings, ceramic and hybrid bearings, stainless steel bearings, miniature bearings, shafting, couplings, screws, socket cap, dental bearings, magnets, sprockets, timing belts and pulleys, corrosion resistant - see the full listing in the Online Catalogue. We have excellent Freight Rates within Australia and worldwide. We offer a choice of delivery with a signature required, or cheaper options with no signature required. The no signature required options are at the customer’s risk once the goods leave our store.
Using the links throughout this site you will find extensive information including catalogues, technical data, and other product specific information. We sell our products worldwide through our online store and our overseas freight rates are competitive for fully traceable courier delivery.
Miniature Bearings Australia is part of MBA Group offering a select range from the MBA Group catalogue.
Miniature Bearings Australia products are not authorised for sale into the USA or Canada due to the reluctance of Australian insurers to provide product liability insurance into those two countries.
Information on this website is Copyright Miniature Bearings Australia 1997. All rights reserved.