Inzaption's core offering is the rerating of existing ASME pressure vessels and shell-and-tube heat exchangers. Inzaption has extensive experience with this work - from small diameter tanks all the way up to 100+ foot tall columns.


Complete calculations to safely rerate equipment to a different pressure and/or temperature can be provided.


Why Rerate a Vessel or Heat Exchanger?


  1. The process requires a higher pressure and/or temperature than the existing MAWP.

  2. The remaining thicknesses of the unit's components are below their original design criteria thus requiring a lower MAWP to extend the life of the unit.


In both cases, the useful life of the unit is extended further reducing the overall lifecycle cost.


Types of Pressure Equipment:

  1. Pressure Vessels constructed to ASME BPVC Section VIII, Div. 1 or 2.

  2. Shell-and-Tube Heat Exchangers constructed to ASME BPVC Section VIII and TEMA codes.


Standard Process:


Inzaption will utilize the original drawings, manufacturer's forms, and all available inspection data to perform a thorough analysis of the unit at the new desireable MAWP.


In addition to the unit's internal and external design pressure, all applicable external loading (seismic, wind, insulation, platform, nozzle, etc.) will be accounted for when evaluating the MAWP of the unit.


Iterative "What if" analyses can be performed to help clients understand the governing components and the estimated remaining life of the unit at different possible rerated MAWPs.



Standard Deliverables for Rerating/FFS Services:

  • Detailed report summarizing the analysis and results.

  • If applicable, Remaining Life Estimates per API-510.

  • Supplemental Fitness-For-Service Calculations (if required) per API-579 due to excessive general/local thinning or pitting.

  • Supplemental FEA analysis of critical nozzles if warranted.

  • Minimum thickness values for all components at the rerated MAWP and all included loading (seismic, wind, insulation, platform, nozzle, etc.)

  • Applicable code calculations, best practices, and methodology consistent with ASME, TEMA, NBIC, API-510, and API-579 codes.





Vessel & HTX Rerating