Buttering welding

[starships]

Gentleman

We're fabricating the pressure vessel. But due to short length(approx. 5~6mm) of plate with width of 1,000mm, we're planning to do buttering welding at joint to recover the gap.
Is it possible and allowable way? Relevant PQT will be performed and witnessed by Authorized Inspector.

Base material is P355 NL1 and Electrode is E7018-1. PWHT required

 

[gr2vessels]

Short answer is yes, the code does not prevent you doing that.
However, have all other venues been investigated and discarded, like fabrication tolerances, maximum welding gap, etc. After all, you are talking a measly 5-6 mm gap for bridging...
Cheers,
gr2vessels

 

[weldstan]

Assuming that you have access for welding from both sides and you will use, there are a number of easier methods; e.g., flux back up tapes, ceramic backing, steel backing strip. Also the gap can readily be fused with the proper process (GTAW or GMAW) by skilled welders.