pre heat

[Shane Kavanagh]

Not sure if i got your question right but my understanding is it would be 25mm. See attached sketch, is this what you are asking?

Regards
Kav
sketchA.jpg

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Kav

[Flash]

Hi Kav it has been mixed up now I have to try and work out how to combine them
Ugh
R
GF

[tiggerfaebigger]

Hi Flash,
Annex I in D1.1 :2008
Thanks for your input.
TFB

[tiggerfaebigger]

Hi Flash,

Thanks for your reply,
You know your stuff mate.

However if you look at tech note 11, clause A4.7.3, which states “where the joint restraint is of unsual severity…..employ strongbacks to adequately simpulate restraint”

Unsual severity restraint will mean most structural tie-in welds (SP) will be under this class. 

Do  you think most engineering companies would take this into account when they run their PQR and hand the welder the wps to go and weld the joint?

I agree with you on pre-heat, but an appendix in AWS D1.1, a bit off the subject here,  has a section on restraint and increases preheat accordingly through calculations, and i know that their basic preheats seem to be pretty low compared to australian standards, however does 1554 take restraint  into account when working preheats out?

Look forward to your comments,

Tigger fae Biggar

[Flash]

Hi TFB
Thank you for the compliment, but I am still learning as well, I think there is lots we can learn from each other
I rarely refer to Tech Note 11 because in my humble opinion it is not a practical document, it is more a theoretical document and often conflicts with AS1554.1
I do not think companies would take it into account because the WPS does not just cover the highly restrained joints it covers normal join ts as well, AS1554.1 allows you to increase preheat without the need to re-qualify, so it comes down to the welding supervisor understanding the situation and if anything urr on the side of caution with preheat and understand hydrogen diffusion

High restraint in my opinion is usually an issue with thicker sections, thinner sections ‘typically yield’ rather than provide the restraint

Its been a while since I have looked at D1.1 what appendix is it I will have a look
R
Flash

[Shane Kavanagh]

I think this thread has been mixed up with the other thread also called pre heat  8)

Kav

Kav

[bulldog39]

If you know the travel speed and the amps for a welding procedure .What is the formula for working out the Volts. Thanks Bulldog 39

[bulldog39]

Can any body please give myself the formula for calculating the travel speed ?

Many thanks……..Bulldog39

[bulldog39]

If i have a 40mm tapered plate being ,say t1. Being a single bevel butt ,joined to 20mm plate not tapered t2, plate and the taper of the 40mm plate is150mm .What would be the average thickness over 75mm be  to work out pre heat calculations as per w.t.i.a. tech note 1. Can anybody please help. Many thanks Bulldog39. 🙁

[Flash]

mm traveled / time in seconds x 60
R
Flash

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