Manufactura

Non-Contacting Bellows Seal for Cryogenic Applications

Type 285

Non-Contacting Sealol® Metal Bellows Seal

Type 285
Non-Contacting Sealol Metal Bellows Seal
The Type 285 seal is the firstnon-contacting welded metal bellows seal to be applied to cryogenic applications. John Crane’s expertise in non-contacting technology (US patent number 4,889,348), combined with a specially designedSealol bellows, ensures high performance, even in the toughest cryogenic applications.

Unique Spiral Groove Technology
As the worldwide leader in spiral groove technology, John Crane is the firstto utilize non-contacting seals in cryogenic applications. The John Crane spiral grooves enable the seal to operate on a gas film by gathering and compressing the vaporized liquid. As the gas is forcedtowards the closed groove ends, the pressure rises, which creates a cushion to separate the sealing faces. Since the seal faces do not contact, dry-running and face wear problems, which areassociated with conventional contacting seals, are virtually eliminated.

Sealol Bellows Design
Since the 1960s, our metal bellows experience in diverse industries, such as oil and gas, chemical, pulp andpaper, municipalities, utilities, pharmaceutical, and food processing, has proven the soundness of Sealol’s welded metal bellows design. Extensive computer modeling and testing have assured thebellows’ performance through all operating parameters. Consequently, the metal bellows design enhances the Type 285 seal reliability.

Applications
The Type 285’s compact design fits most popular cryogenicpumps without modification. It is available in various seal housing arrangements: flanged and left- or right-hand-threaded. The design and materials of construction meet the industry safetyrequirements, allowing the Type 285 to seal all of the common industrial liquid gases, including: • Oxygen, • Nitrogen, and • Argon.

Sealol® is a registered trademark of John Crane.

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