PCHE
PCHE
(OP)
We are looking at using PCHE (heatric) for a clean gas/cooling water service operating at temperature above 50 deg C (but below 100 deg C) in an offshore marine enviroment.
From what I understand, 316L is not accpetable for application above 50 degC in an offshore marine environemnt and due to this cause, application of SS316L, Duplex and Super Duplex have been limited to 50, 100 and 100 deg C respectively.
For the service and temperatures above, vendor has offered the headers constructured of duplex material, but the core is retained as 316L. The core, will be exposed to marine environment.
Can someone please comment further?
From what I understand, 316L is not accpetable for application above 50 degC in an offshore marine environemnt and due to this cause, application of SS316L, Duplex and Super Duplex have been limited to 50, 100 and 100 deg C respectively.
For the service and temperatures above, vendor has offered the headers constructured of duplex material, but the core is retained as 316L. The core, will be exposed to marine environment.
Can someone please comment further?





RE: PCHE
RE: PCHE
Service fluid,
Hot side: Compressed clean/dry hydrocarbon gas
Cold side: Cooling water (potable quality) with O2 scavenger injected and controlled chloride content.
RE: PCHE
RE: PCHE
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdo/
RE: PCHE
The service these exchangers are in is like 2500# class. So I think the plates will indeed be subjected to some stress, hence the concern over CSC.
RE: PCHE
RE: PCHE
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdo/
RE: PCHE
In the past the vendor has supplied CRA (duplex/superduplex) shrouds welded on the exchnager to prevent exposure of the SS core to the marine environment. After a while the shrouds developed cracks at the weld area due to frequent "expansion and cooling effect". To overcome this failure, the vendor have now included a breather vent, but I guess anything that breathes out may breath in too, sooner or later.