MACHSEAL 101

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.

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.

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.

Section through anti-rotation configuration 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.

Rotary Mating Ring Configurations The mating ring is critical for proper seal performance with the MACHSEAL. It’s 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.

MACHSEAL OTHER 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 cup’s machining process rather than welded on. Easily disassembled for low cost repair. Handles large variation of operating conditions. Specifically engineered for your application.