Next comes the application of a primer, which serves as a bonding agent between the old surface and the new layer of fiberglass
However, it's important to note that carbon steel bits have their limitations
What are oil seals?

Other important factors are ensuring the hardness and roughness of the shaft are correct. A shaft hardness of HRC 45 is recommended for a rubber sealing lip, with a roughness of Ra 0.4-0.8. A higher shaft hardness of HRC 60 and shaft roughness of Ra 0.1-0.4 is recommended for a PTFE lip.
(the volume of oil, etc., pushed back at the lip contact area per unit of time)
No single physical property of rubbers is responsible for the successful performance of an oil seal or ‘O’ ring. The ultimate tensile strength, breaking elongation, modulus, shore hardness, creep and stress relaxation in tension and compression loads are all important physical properties that characterize a seal or ‘O’ ring. Compression strength and set together with stress relaxation or decay are important for effective sealing. The difference in these properties in a swollen seal is highly critical. An optimum swelling value in a fluid medium is a desirable feature. De-swelling decreases the seal pressure against the wall of the housing where the seal is fixed, leading to leakage. Over swelling minimizes the physical properties of the rubber. Seals made of polysulfide rubbers have extreme fuel resistance but undesirably high compression set. The effect of temperature on the seal is an important factor. Swelling under stress can increase at higher temperatures and a suitable compounding technique should be adopted to reduce this effect.
The basic principle of sealing is straightforward – the flexible lip is held against the rotating part (usually the shaft) whilst the casing (or O.D.) is pressed into the housing or bore and holds the seal in place. The sealing lip needs some form of lubrication to avoid overheating and is usually energized by means of a garter spring.
PTFE oil seals
GV
Oil Seal 75x100x10 A Complete Guide
There are several materials used to manufacture oil seals. They are discussed below.
Most standard oil seals have to comply with the DIN 3760 and ISO 6194 standards. Different standard types of oil seals are available that comply with these requirements.


Rotary Wheel Of Auto Parts
Oil seals for steel production equipment

• Super helix seal (seal with one-way two-step screw)