For larger drill bits, a taper shank may be used. Taper shanks have a gradual taper that allows them to fit securely into a drill press or lathe

Different Types Of Bearing Seals


Silicone
Wide temperature range
Commonly used in low temperature applications
Very prone to mechanical damage during fitting
Case study 2: Silicone oil leakage
There is a British Standard laid down for the control of synthetic rubbers. BS 3574 (1989) helps to determine shelf life – for instance, Nitrile (NBR) and Polyacrylic (ACM) are Group ‘B’ rubbers and have a 7-year life, whilst Silicone (VMQ) and Fluoroelastomers (Viton®) are Group ‘C’ rubbers and have a 10-year shelf life. PTFE and Leather do not come into this category but like the others should be kept in the original packing for as long as possible away from direct light, dust, and humidity. Ozone, which can also be produced by battery-driven forklift trucks has a very bad effect on synthetic rubbers. Finally, protect the sealing lip – DO NOT hang the seals on nails, wire etc.
Common Oil Seal Failure Causes
The oil seal is generally composed of three basic components: sealing element, metal shell and clamping spring.Types of oil seals include single and double lips, rubber or polymer, metal housing, spring loaded, and internal, external and axial guides.
Rotary Wheel Of Auto Parts
Table 14.1. Fluoroelastomers Used in Oil Aging5