ASME VIII - UCS56

By welder13 Date 09-01-2009 17:03

Hello!

I would like to ask you about the UCS 56 table of ASME VIII division 1. This tables says the minimun holding time for postweld heat treatment.
For some material, P4 for example, the table says as follows: Up to 2in, 1hr/in and 15 min minimum. This means that if I have 1 in, I would do a heat treatment of one hour, if I have 1/2 in it would be in half an hour, if I have 3/16 in, I would have to do it in a minimun time of 15 minutes, and so on. The same would happen for material thicknesses over 2 inches to 5 inches. And over 5 inches, the heat treatment would last 5 hours plus 15 minutes for additional inch. This means that if have 6 inches, it would last 5 hours and 15 minutes. So far so good. (or so I think).

My problem is when I get to P9 or P10 materials. This is what the table says: "1 hr minimum, plus 15 min/in for thicknesses over 1 in."
Ok. Let's see what I have:
If I have 1/2" -> 1 hour
If I have 1" -> 1 hour
If I have 2" -> and here is my problem. Does the heat treatment should last 1 hour and 15 minutes? or 1 hour and 30 minutes? To clarify a little, what I need to know if the code means 1 hour and 15 minutes PER inch over 1": if i have 2" that's 1" + 1" (that's 15 minutes per inch=30 minutes). I'm doubting because for these material doesn't say "for each additiona inch", in which case this would be as easy as I wrote in the previous paragraph.

I think I have accomplished to confuse you and me more than I was before, but still I hope you understand my doubt and can help me.

Thanks in advance.
Federico

By js55

Date 09-01-2009 18:36

My interpretation is 1hr and 15 minutes for 2". If you add 15 minutes to the first hour to get your 1hr and 30 minutes you have essentially made your 1 hr min a 1hr and 15 minute min and the 1 hr min doesn't make any sense. In which case you would now need 1 hr and 45 minutes for a 2" piece, using the same logic. In which case you would need 2 hours using the same logic. It would be like wipin your azz with a hoola hoop there would be no end to it.
However, if you're dealing with UCS-56 you have an AI. Ask him. You'll want to agree with him prior to his review anyhow so you don't have any uh-oh's. Also, whenever you get in these "interpretation" situations for Code work I'm guessin your AIA has someone sittin on the Code Committee.

By Mikeqc1 (****)

Date 09-01-2009 23:50

You've sparked my intrest I'm going check this out tomorrow.
I dont think i would have thought of it that way, unless prompted by the Spec.

MDK

By welder13 Date 09-02-2009 00:56

Thanks! I would really apreciate if you could clarify the matter ...thanks again...

By 464238

Date 09-02-2009 14:31

I have fabricated several vessels under ASME Section VIII, Div. 1 and Div. 2 and my interpretation has always been for a 2" thick vessel is

1 Hour Minimum + 15/Min an inch which equals 2 Hours. I would always ask the post weld heat treatment contractor to add and additional 15 Minutes to take in consideration the different thicknesses of the vessel and the different heating times of each part of the vessel so that I can be covered. (it doesn't hurt because the times mentioned above are minimums)

By welder13 Date 09-02-2009 15:02

I'm sorry. I'm not following. How do you reach to 2 hours? Thanks.

By ssbn727 (*****)

Date 09-02-2009 19:00 Edited 09-02-2009 20:15

Good question Caballero/Vaquero Federico de Argentina!!! ;) That is, unless this person is also adding an extra 15 minutes to each inch for good measure which only then result in two hours, and that would be the only logical explanation, but why bother just saying only fifteen minutes and instead say one half of an hour for each inch plus the one hour minimum to come up with two hours total??? And this still doesn't make sense even presuming that is what this person meant!!! ;)

May I ask the name of the university you're currently studying at? ;) Btw, "Bienvenidos al Foro de Soldadura mas Mejor en el Mundo" Federico!!! Mucho Gusto para esta con nosotros - Caballero/Vaquero!!! :) :) :) Rough translation: "Weldcome" to the World's Greatest Welding Forum!!! We are very much happy to have you here amongst us - horseman/cowboy!!! :) :) :) Otherwise known as "Gaucho's" in Argentina! ;) Please forgive my spanish as it is very, very "rusty" so please try to remain with the American English or the English dialect of your choice if you prefer instead, so once again "WELDCOME!" :)

Respectfully,
Henry

By welder13 Date 09-02-2009 19:30

Henry! Really apreciate the sense of humour! gracias! Very imaginative with your "weldcome". :-)
I will try to do my best with my English (which could be very, very rusty too).
I study at UTN (Universidad Tecnológica Nacional). I'm doing quite nice, but you know how this is. Working and studying and everything...sometimes gets hard..

Sorry to ask again. But I still don't understand the real meaning of this part of the Code. Independently of the time you add "just in case", if I would have to adher strictly to the Code, How long the heat treatment for 2 in thickness would last? why?

Thanks a lot
Regards,
Federico

By js55

Date 09-02-2009 19:58

Its 1 hr and 15 minutes for a 2" T.
1 hr minimum "PLUS" 15 min/in for thickness "OVER 1in".
You only need to add to the 1" in 15 increments after 1" T.

By ssbn727 (*****)

Date 09-02-2009 20:13 Edited 09-02-2009 21:17

Hello again Federico!
I think Jeff answered the question with his always "eloquent" yet, straightforward response! ;) And by re-reading his earlier post in this thread, Jeff sums it up quite well IMHO. ;)
As to the why this is the case, I would defer to the link I posted below:

http://www.googlesyndicatedsearch.com/u/cammsm?q=Post+Weld+heat+treatment&btnG=Search&hl=en&domains=msm.cam.ac.uk&sitesearch=msm.cam.ac.uk&ie=ISO-8859-1&sa=2

Actually this one more focused on PWHT of P-4 steels:

http://www.googlesyndicatedsearch.com/u/cammsm?q=Post+Weld+Heat+Treatment+of+P+-+4+steels&btnG=Search&hl=en&domains=msm.cam.ac.uk&sitesearch=msm.cam.ac.uk&ie=ISO-8859-1&sa=2

So Federico! Are you leaning towards majoring in the Material Sciences??? I ask this because, there is a "plethora" of reference information, and links to some excellent material science/ metallurgy web sites in the Metallurgy section of once again: "The World's Greatest Welding Forum" (Sorry but, I couldn't resist again!) for you review at your leisure of course!!! ;)

Respectfully,
Henry

By welder13 Date 09-03-2009 13:29

So I believe that what I'm thinking is not correct. I mean, when it says 15 min/in over 1 in, I understand different from what you are saying. But perhaps this is only product of my "no-speak-in-english".

Thanks everybody.

And...what is IMHO? :-D

By jwright650 (*****)

Date 09-03-2009 13:44

>And...what is IMHO?

In My Humble Opinion

By ssbn727 (*****)

Date 09-03-2009 14:09 Edited 09-03-2009 15:08

Hi Federico!

Maybe if I translate in Spanish (very crude Cuban dialect so bear with me please!) you might get a better understanding okay?

Para el primer pulgara, usa Sesenta minutos o una hora... Entonce para el segundo plugara, usted tiene que anadir, aumentar, acrecentar, juntar, o a contribuir quince minutos nada mas!!! Ultimamente usted vas a tener Setenta y cinco minutos o una hora y Quince minutos total usando este formula describido - comprende? ;)

Translation using my own words:

For the first inch, use sixty minutes or one hour... Then for the second inch, you have to add fifteen minutes nothing more!!! Ultimately you will have Seventy-five minutes total, or One hour and Fifteen minutes total using the formula described - understand, comprehend? ;)

IMHO = In My Humble Opinion :) :) :)

Respectfully,
Henry

By js55

Date 09-03-2009 15:04

IMHO
In My Humble Opinion

aka

I Might Have Overstated :)