ASME - Butt joint full penatration permissible gap?
ASME - Butt joint full penatration permissible gap?
(OP)
Hi,
what is the maximum permissible gap in a buttweld for plates 1/4" thick without backing? Where can I find it in the ASME code?
Thanks,
Vincent
what is the maximum permissible gap in a buttweld for plates 1/4" thick without backing? Where can I find it in the ASME code?
Thanks,
Vincent





RE: ASME - Butt joint full penatration permissible gap?
What does your WPS state for an open root, butt weld root spacing tolerance? There are no maximum root spacing requirements for butt welds in the ASME B&PV Code, this is a process detail.
RE: ASME - Butt joint full penatration permissible gap?
Maybe you refer to part UW or Sec. IX ASME Code, or AWS welding hand book.
RE: ASME - Butt joint full penatration permissible gap?
RE: ASME - Butt joint full penatration permissible gap?
Metengr and vesselfab are correct. If you reference Sec IX you'll note for most of the common processes, root spacing is a non essential variable. This means that while it must be specified on the WPS, a change can be made without requalifying the procedure. Some common sense must be applied here. There are some processes such as laser beam welding where root spacing is an essential variable meaning that a change would require requalification of the procedure.