Inclusions in casting A216 WCC vs 8620 pressure vessel
Inclusions in casting A216 WCC vs 8620 pressure vessel
(OP)
I have a pressure vessel housing cast with A216 WCC material. Experiencing a lot of inclusions exposed during machining. Foundry wants to change material to 8620 but I cannot verify this 8620 material is pressure quality. This part has internal and external threads so stainless is not an option for me. Thanks, AWOL





RE: Inclusions in casting A216 WCC vs 8620 pressure vessel
If this is a pressure vessel housing, you have several other options for steel or low alloy steel castings under ASTM specifications versus using a cast version of 8620 alloy steel (which does not conform to any of the ASTM casting specifications).
Your options could be various carbon or low alloy steel grades under ASTM A 217, ASTM A 148, ASTM A 27 or other ASTM Casting Specs depending on your specific application.
Is the pressure vessel built to ASME Boiler and Pressure Vessel Code Section VIII, Div 1 requirements?
What is the nature of the housing? Is it welded to the pressure vessel or integral with the vessel?
What are the design service conditions?
RE: Inclusions in casting A216 WCC vs 8620 pressure vessel
8620 grade specification for a casting does not exist. But broadly the castings are manufactured to this chemistry. As suggested earlier there are other grades of cast materials for pressure vessel appplications.
RE: Inclusions in casting A216 WCC vs 8620 pressure vessel
RE: Inclusions in casting A216 WCC vs 8620 pressure vessel
Is the pressure vessel built to ASME Boiler and Pressure Vessel Code Section VIII, Div 1 requirements? No code requirements. Company internal requirements to use pressure grade material or, if using a non pressure grade material, provide documented testing to validate the use of the material in our application.
What is the nature of the housing? Temporarily attached to pipeline like a valve during servicing. Never becomes part of permanent pipeline system. Is it welded to the pressure vessel or integral with the vessel? No, NPT threads.
What are the design service conditions? Test presure 415 psi. MaOP 285 psi. Gas, oil, water.
Of the other material that have been recommended, A148 looks good but will require testing. The others A27 , A487 require HT and / or test with each lot.
I have quotes out to other casting vendors. Thanks for the help.
RE: Inclusions in casting A216 WCC vs 8620 pressure vessel