Mechanical seal john crane
Type 48VBF
Low leakage, high temperature shaft seal for uncooled boiler-feed-water
The Type 48VBF is a single seal that can operate without a cooling water system (external heat exchanger, API Plan 23) in critical high temperature pumps. In systems such as boiler feed water (hot, demineralized, deaerated water) for fossil-fuel steam power plants or within the utilities section of a process plant, can simplify operations and significantly reduce water consumption.
Marginally cooled or even uncooled, the Type 48VBF can run 20 °C hotter than competitive solutions, so will run longer in marginal conditions. Using advanced face technology and assembly techniques, unique “hydropads” allow the seal faces to remain flat in operation, increasing lubrication efficiency and so enabling the seal to run cooler.
The 48VBF is an easy upgrade from the existing John Crane 48V seal, requiring nothing more than changing the primary ring.
Product Description Type 48vbf
The 48VBF seal is a single cartridge, stationary head, O-ring pusher seal that can operate without an external heat exchanger (API Plan 23) in critical high temperature, medium
pressure pumps. This is ideal for application in Boiler Feed pumps, which inject feedwater (hot, demineralized, deaerated water) into the boiler at fossil-fuel steam power plants or within the on-site generation plant of a processing or
manufacturing site.
The main risk of seal failure is due to numerous problems associated with the heat exchanger seal support loop, resulting in the BFW pump shutting down and the boiler going offline. Common heat exchanger support loop problems include:
• Loss of cooling water
• Undersized heat exchanger
• Incorrectly installed/located heat exchanger and/or piping
• Poor/inadequate venting procedure after outages/shutdowns
• Scale/corrosion build-up within the piping, limiting flow and seal cooling
By allowing operation without that heat exchanger, the 48VBF reduces cost to the end-user for the heat exchanger, piping
and water usage.
Features Type 48vbf
- California Residents: PROPOSITION 65 WARNING
- Plans such as 23 or 21 with heat exchangers are not required
- Rotating mating ring design for reduced misalignment and higher shaft speed capability
- Mating ring outer diameter surfaces entirely exposed to process fluid for enhanced heat transfer
Recommended Applications Type 48vbf
- Centrifugal compressors
- Other compressors
Performance Capabilities
• Temperature: 0°C to 200°C/32°F to 392 °F
• Pressures: Carbon Face: Up to 30 bar g/435 psi g
• Speed: Up to 30 m/s/5900 fpm