Fluid and Turbo Machinery.

1. In Industrial Fluid Power

2.  A hydraulic seal is a relatively soft, non-
metallic ring, captured in a groove or fixed in
a combination of rings, forming a seal
assembly, to block or separate fluid in
reciprocating motion applications.
 Their use is critical in providing a way for
fluid power to be converted to linear motion.

3. Based on Sealing:
A] Positive seals- Do not allow any leakage.
B] Non positive seals- Permits internal leakage.
Based on applications:
A] Static seals- No relative motion mating parts.
B] Dynamic seals- Relative motion mating parts.
Based on shape:
A] O-rings B] Quad rings C] V-packing
D] U-packing E] Cup packing F]Composite seals

6.  Pressure
Depending upon higher or lower pressure
situations.
 Temperature
Leather- below 65 c, Plastics- up to 260 c.
 Operational Speed
Compatibility with oil, Metal clearance,
Alignment, Metal finish, Life expected.

7.  Leather seals
Tough, pliable, resistance to abrasion, wear, stress
& temperature effects.
 Rubbers
Poor resistance to petroleum fluids & rapid aging
when exposed to oxygen or ozon.
 Plastics (Flouro-plastics & Flouro-elastomers)
High heat resistance, compatible with fluids.
 Metals
High pressure, easily bent, hard in compression.