Pipeline Automatic Welding

Currently pipeline automatic welding become more and more popular, especially for long distance project, it has the advantages of high efficiency , reliable welding quality, also easy welder training etc.

There are two types of automatic welding for pipe:

Option 1: Automatic internal welding for root pass, then follow by automatic orbital welding for others including filling and capping passes. Comparing to orbital welding ,?internal welding?is faster and more reliable. it does not require backing material for root, for a long pipeline project, internal welding is better choice.

Option 2: Automatic orbital welding for all passes, it also two ways to go

A. Internal line up clamp with backing when?automatic orbital welding, copper shoes are the most popular backing which are usually adopted by contractors, it is very helpful for root pass profile with very low repair rate. Anyhow some project owners concern about the copper contamination, however per studies domestically and overseas, the welding bead copper content is very low, even lower than copper content in base material.

Copper shoes consumption would be another issues, however if adopt PGMAW for root and program correctly with right setting including current, voltage etc , the experienced welders should get over 500 joints on a set of coppers and that can be considered wear and tear.

B. Internal line up clamp without backing, this is called "one-side welding with back formation". In this case, RMD / STT/ Rootwise/CMD welding would be considered, the welding time is longer than type A, in addition per project data, the repair rate is higher, it also require high skilled welders.

Remarks: RMD from Miller, STT from Lincoln, Rootwise from Kemppi, CMD from Fronius