Type 21
Manufacturer: John Crane
General duty Elastomer Bellows Shaft Seal
Our general purpose Type 21 mechanical seal has become the industry standard for OEM designers.
Automatic adjustment compensates for abnormal shaft end play, run out, primary ring wear and equipment tolerances.
The Type 21 is ideal for use in centrifugal, rotary and turbine pumps, compressors, chillers and other rotary shaft equipment. It is also commonly used by the wastewater and water systems industries for applications such as waste treatment, potable water and HVAC.
• The drive band's "dent and groove" design eliminates overstressing of the elastomer bellows to prevent bellows slip and protect the shaft and sleeve from wear.
• Non clogging, single coil spring provides greater dependability than multiple spring designs and will not foul due to fluid contact.
• Flexible elastomer bellows automatically compensates for abnormal shaft end play, run out, primary ring wear and equipment tolerances.
• Non clogging, single coil spring provides greater dependability than multiple spring designs and will not foul due to fluid contact.
• Flexible elastomer bellows automatically compensates for abnormal shaft end play, run out, primary ring wear and equipment tolerances.
TEMPERATURE LIMITS40°F to 400°F/ 40°C to 205°C (depending on materials used)
PRESSURE LIMITS150 psi(g)/10 bar(g)
SPEED LIMITSUp to 2500fpm/13m/s, depending on configuration and shaft size