Type 680
Manufacturer: John Crane
Low temperature, General Duty All Alloy 20 Edge welded Metal Bellows Seal
The Type 680 is the ideal seal for general purpose applications. Its rotating Alloy 20 bellows provide corrosion resistance in a broad range of corrosive media. Its cost effective design, combined with a reliable performance history, has made the Type 680 a standard for low temperature applications found in the chemical, water and wastewater, pulp and paper, and utility industries. The seal is available with hard faces for abrasive applications and a wide range of elastomers to cover a broad range of applications.
• Manufactured with a 45 degree tilt edge at the bellows' inside diameter to disperse stresses and maximize operating life.
• Superior nesting ripple plate shape with a three sweep radius; this plate design allows the bellows device to be flexed repeatedly without the metal being stressed beyond its endurance limit.
• Self cleaning design - rotating bellows throw off suspended particles that clog spring type seals. This self cleaning action eliminates the need for external flushing, filters or cyclone separators and their associated costs.
• World class bellows manufacture - our bellows production facility has an outstanding manufacturing process with state of the art stamping, welding and testing technology.
• The bellows incorporate all of the design features resulting from key engineering competencies, such as metallic thin shell methodology, tribology and fluid sealing technology, and thin film/fluid mechanics
STANDARD MATERIALSCarbon face: To 200C/400F - -Tungsten Carbide or Silicon Carbide face: 150C/300F -
PRESSURE LIMITSVacuum to 360 psi(g)/25 bar(g)
SPEED LIMITS5000fpm/25m/s