The advantages are low friction and minimum power consumption, the possible use even in case of insufficient lubrication, operating range of -130º c to +200º c and much more: high chemical resistance and a low breakaway torque after standstill. Further, the PTFE, when heated, can” remember” its original form and return to it (phenomenon known as” plastic memory effect”).Therefore, this kind of seal do not need the old school metallic spring.
For more information on the characteristics of Oil Seals click on some of the links below:


Some disadvantages of NBR are poor ozone, sunlight and weather resistance as well as limited high temperature and flame resistance. For higher temperature resistance, a much better material to use is Silicone.
Cracks or swelling

Oil Seals Enable Your Equipment to Operate Efficiently
Check the faces of the head and block for flatness. Alloy heads in particular can distort and then leak.
Most oil seals consist of some basic elements that configure their structure, such as the sealing element, the metal case, and the spring:
A patent for an oil seal was filed by Nelson Thomas Edward on August 12, 1937, and published a year later. There were two purposes described. The device was to provide an oil seal between a fixed housing and a rotating part. The seal is described as