Welding in Cold Weather condition 1

[demsha]

Hello All,

Our client is connecting two screw piles by welding a collar (sleeve) into it. However they were doing this welding when outside temperature was around -30 ⁰C below.
After our repeated screaming, contractor began to weld in a covered tent. Can anyone tell me where I can find answers to following questions;

1. Does the contractor requires to preheat the weld area? if so what temperature?
2. Does the inter-pass temperature has to be high? what temperature?
3. Does the contractor requires to use a blanket to wrap up weld area? at what temperature he has to cover with a blanket and remove?
4. What is the minimum temperature that welding cannot be done?

Thanks in advance.

 

[weldstan]

1. Depends on Code and Contract requirements and the base netal & thickness to be welded. For low carbon steel preheat should be performed whenever temp < 0 C.
2. See 1. above.
3. See 1. above.
4. See 1. above.

The Contractor must make a sound weld. How he does it is up to him and the Contract & Code requirements.

 

[kingnero]

EN 1011 provides some info, as does the book written by F. Coe: "Welding Steels Without Hydrogen Cracking".

I'd say, if he follows a WPS that is covered by a PQR, that's as good as it gets. If not, you're guessing at best for the achieved quality.

 

[gtaw]

If D1.1:2010 is applicable, try clause 5.12.2.

Codes will not tell you why the provision is included in the code, but they are typically based on lessons learned from "bad experiences."

Best regards - Al

 

[weldtek]

What min preheat does their WPS call for?