6G pipe specs

[levw49]

Hi everyone, I'm putting myself through a 6g code in tig and I'm buying the pipe myself and really need some advice on what would be a good general diameter and wall thickness to go for. At the moment I'm thinking 100mm x 5mm but this is just a rough estimate. Because it's not for a specific job as such I really have nothing to go by so I'm looking at a good all round size whereby I can specialise later. Your help would be massively appreciated as I don't have the expertise or background knowledge to judge this.
Thanks for reading! Andrew.

 

[Jim_gsxr1000]

Have a looks on welding tips and tricks.com id say 6" schedule 40 or schedule 80

 

[hotrodder]

6g is a welding position, not a welding code [/pedantic]. There are lots of different codes that use this posistion as it's a way of combining vertical/horzontal/overhead into one. There are still restrictions with regards to pipe diameter and wall thickness that can be welded and these are determined by the dimensions of the test piece(s) and the specific code.

Gross generalisation would be 0.5d to 2d and 0.5t to 2t or 0.5d to unlimited and 1t to unlimited where d = dia and t = wall thickness

This means it's fairly common to do at least 2 sizes to get qualified for a decent range of pipe because small dia stuff doesn't go as heavy in wall thickness as larger dia stuff if that makes sense i.e. even when a 2" pipe would cover you for 1" dia and bigger the 2" pipe doesn't exist in wall thickness that would qualify you to weld larger dia pipe

Be aware that codes typically expire within 2 years, sometimes in 6 months if you're not using them i.e. there's no documentation that you're welding to the standards

Are we talking something 'basic' like BS4872 which is a test of the weldors ability to produce a sound weld or ASME 9 / EN287 which is about being able to produce the goods to a specific welding procedure?

 

[levw49]

You are correct, I should refer to it as a position and not a code. Well my plan is to get into power station work eventually, I know someone who can put my name forward but I have to be able to weld to there standard so I guess we're talking ASME 9 territory. Above all I suppose I want to prove to myself that im capable of doing this, i'm not in a rush but I want to be sure i'v got the correct steps in place to get me there, and the work piece in question plays a large part of it.
I have been looking at some of Jody's videos for welding tips and tricks and he says that if you can show someone that you're capable of welding 2" 80 schedule pipe (am I correct in saying that's 5mm wall thickness) then they can be pretty confident in your ability to weld any size pipe. Would be interested to know what your thoughts are.
Thanks for the info guys it really is appreciated!
Andrew

 

[Jim_gsxr1000]

generally the smaller you go the more difficult it is, at work, the guys put the roots in with tig then fill the remainder with stick

 

[backpurge]

Andrew, I see you are in the West Midlands, I would give the guys at Babcocks training school at Tipton a ring and ask them for advice on the best route for you

 

[levw49]

Thanks for that, iv given them a call and left a message with someone who can hopefully put me in touch with one of their instructors. Thanks for that, iv been racking my brain but missed that one! Cheers!