MACHSEAL 101

1
MACHSEAL 101
2
Design Information

• Stationary rotary face seal that utilizes axial
  spring force to positively mate the optically
  flat seal face against an optically flat mating
  surface (shaft shoulder, bearing inner race or
  mating ring).
• Cup and seal case are robust because they are
  machined rather than stamped or molded.
• Anti-rotation design uses two (2) tangs on the
  seal case that engage slots in the cup which
  permits fluid movement in this area.
• Removable take apart design allows repair,
  replacement and inspection of internal parts.
• O-ring quality in accordance with AS871 for a
  positive secondary seal.
• Temperature range is limited by the elastomer.
• Low pressure, high pressure or reverse pressure
  can be accommodated by proper adjustment of seal
  ring diameters.
• Special designs available.
• Spring energized PTFE lip seal
• Solid outside diameter cup with internal flats
  for anti-rotation.

3
The wave spring is a crest to crest series
stacked configuration that decreases the spring
rate proportional to the number of turns thus
providing small variation in the load over the
entire operating range.
4
Spring Energized PTFE Lip Seal

• Spring energized PTFE lip seal for applications
  that exceed operating limits for o-rings
  (elastomers).
• Uses the majority of the same components (seal
  case, seal ring, wave spring, and retaining ring)
  as the o-ring secondary seal standard.
• Cup design uses a counterbore gland configuration
  and a washer to accommodate the lip seal.
• Lip seal cannot accommodate reverse pressure
  because it seals pressure in only one direction.
• Low pressure or high pressure can be accommodated
  by proper adjustment of seal ring diameters.

5
Solid Outside Diameter Cup
Design Information

• Retrofit version where the cup outside diameter
  cannot have slots and must be one diameter.
• Cup and seal case are robust because they are
  machined rather than stamped or molded.
• Anti-rotation design feature utilizes three (3)
  external flats on the seal case that engage three
  (3) internal flats in the cup.
• Removable take apart design allows repair,
  replacement and inspection of internal parts.
• O-ring secondary seal and spring energized PTFE
  lip seal configurations are available.

Section through anti-rotation configuration
6
Rotary Mating Ring Configurations

• The mating ring is critical for proper seal
  performance with the MACHSEAL. Its mating face
  must be flat, smooth and be properly mounted to
  the shaft in order to prevent face distortion,
  slippage, leakage and misalignment (out of square
  condition).

Shaft Shoulder / Bearing Inner Race. Applications
with limited axial space. Shaft shoulder must
have proper surface finish which is difficult to
achieve. Bearing inner race requires a special
bearing with a tightly controlled fit onto the
shaft with a secondary seal o-ring between the
race and the shaft.
Clamped Ring Applications that do not require a
secondary seal because they are beyond limits of
elastomers. Shaft sleeve axially clamps the
mating ring rigidly against the shaft shoulder or
bearing inner race. The shaft shoulder, bearing
inner race surface the sleeve must be square to
the centerline and have the proper surface finish
to be an effective seal.
Clamped Ring with Elastomer Applications similar
to the clamped ring except with a positive
secondary seal in the shaft. Elastomer material
limits the temperature range.
Solid Ring, Mechanical Drive Applications where
clamping is impractical, mating ring has a
positive mechanical drive using either a pin
(shown) or tang/slot configuration into a shaft
shoulder or bearing inner race. An o-ring between
the mating ring and the shaft provides a positive
secondary seal.
7
MACHSEAL

• Machseal advantages over other designs include
• Machined cup for precision, strength and
  rigidity.
• Seal case with inserted seal ring has improved
  heat dissipation as compared to solid seal ring
  designs.
• Accurate control of o-ring squeeze.
• Lapped and polished sealing surfaces for positive
  dynamic radial and axial sealing.
• Anti-Rotation features are integrated within the
  cups machining process rather than welded on.
• Easily disassembled for low cost repair.
• Handles large variation of operating conditions.
• Specifically engineered for your application.

OTHER