API Plan 31 & 32

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API Plan 31


Recirculation from the pump discharge through a cyclone separator delivering the clean fluid to the seal chamber


Required Media Characteristic-

  • Suspended solids contains

  • Very dirty process fluids or slurry fluid not allowed 

Feature -

  • Media from pump discharge enter the cyclone separator where clean media is sent to the seal chamber, and remaining fluid with high solid contains is sent to the pumps suction .

  • Removes entrained solids from the process fluid.

  • Pump throat bushing is recommended.

  • Ensure use for services containing solids with specific gravity twice or more than that of process fluid.

  • Efficiency of a cyclone separator is inversely  proportional to the diameter.



        
API 32

Injection of clean or cool liquid from external source into the seal chamber
   

Required Media Characteristic-

  • Suspended solids contains

  • Poor Lubrication

  • Hazardous  

  • Media dilution is acceptable

Feature -

  • Close Clearance Throttle bush is used to maintain an elevated pressure in the seal chamber and to isolate it from pumped media. 

  • Flush is injected in the seal chamber from an external source 

  • Reduces flashing or air intrusion across seal faces

  • Maintains vapour pressure margin.

                  

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