Charpy impact testing requirements
Charpy impact testing requirements
(OP)
Hi,
when the anticipated temperature (ambience or media) in an oil and gas facility is not going to go below -20F is Charpy impact testing required for the weld procedure?
1. For API wellhead welding to ANSI line pipe, MDT above at -20F
2. Same as 1 above but MDT below -20F
3. B31.3, 31.4, or 31.8 piping with MDT above -20F
4. Same as 3 above with MDT below -20F
I am under the impression from my little knowlege of the code that impact testing is required only for 2 and 4 above, is that right?
If so, how does one determine the test temperature?
Thanks a lot.
when the anticipated temperature (ambience or media) in an oil and gas facility is not going to go below -20F is Charpy impact testing required for the weld procedure?
1. For API wellhead welding to ANSI line pipe, MDT above at -20F
2. Same as 1 above but MDT below -20F
3. B31.3, 31.4, or 31.8 piping with MDT above -20F
4. Same as 3 above with MDT below -20F
I am under the impression from my little knowlege of the code that impact testing is required only for 2 and 4 above, is that right?
If so, how does one determine the test temperature?
Thanks a lot.





RE: Charpy impact testing requirements
that -20 rule will get you in trouble.
RE: Charpy impact testing requirements
Can you please expand on getting into trouble with the -20F rule
RE: Charpy impact testing requirements
RE: Charpy impact testing requirements
For me, the problem with your question is that it covers too much ground. As I'm sure you know, impact testing requirements are driven by the construction code and you've referenced several of them. In addition material types and thicknesses all influence impact testing requirements and you've given several of those. I think you can be pretty sure that 4130 material will not be exempt though.
RE: Charpy impact testing requirements
let me narrow it down.
1. Most of the line pipe welding are between A106B to the same, will this require Charpy for temperature below -20F for that base metal thickness range, considering only ASME B31.3?
2. What about 4130 to A106B for 0.1875" to 1.2" thickness, B31.3 too?
3. Finally, 4130 to the same for the same, API SPEC 6A?
Thanks Weldtek
RE: Charpy impact testing requirements
So if I understand correctly we can condense your question to two materials A106B & 4130, and one code B31.3.
Per B31.3 A106B is exempt from impact testing at -20F for thicknesses up to 1/2". This comes from Table A1 showing A106B as a Curve B material and referencing Table 323.2.2A for temperature / thickness exemptions. For non exempt materials review Table 323.2.2 for testing requirements.
Be sure to use consumables that are qualified by the manufacturer to -20 F or lower.
I didn't spend a lot of time but was unable to locate 4130 listed in Table A1 under several of the common material specifications. if you know the material specification eg A322 or other, provide that and I'll look again.
If the material is unlisted it'll require testing.
RE: Charpy impact testing requirements
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: Charpy impact testing requirements
Thanks a lot for your responses.
What I'm understanding is: For the A106 (P1 to P1, the test is not required for -20F and above), but required for below -20F.
2. If the weld is between API 4130 material and ANSI pipe (A106B), since the weld design is governed by the weaker material (A106B), do I still need to worry about charpy, because the tensile, pressure rating, etc are based on the waeker material.
3. Finally, for the API SPEC 6A application, i.e. 4130 to 4130, does anyone know where in the code that I can find a decision making requirement if I need Charp on those, BTW, they are ordered PSL 1 and the MDT is not below -20F
Thanks a lot.
RE: Charpy impact testing requirements
some are not
RE: Charpy impact testing requirements
You are incorrect. Under B31.3, API 5L & 5LX follow Curve A in Fig. 323.2.2A unless normalized or quenched and tempered. A-106 follows Curve B; impact testing will be required at temperatures > -20 F depending on thickness.
RE: Charpy impact testing requirements
I'm still trying to understand the table and curves completely. But here's a way I can simplify it.
1. For materials X-42, X-46, X-52, A106 grade A, B, and C. for thickness ranges 0.1875" - 1", will welding any combination of the above for services of -20 and higher require charpy on the WPS for thickness upto 0.5", what about thickness higher than that, does that mean charpy will be required even for temperature higher than -20F. this question is per Table/figure 323.2.2A in B31.3
2. What about 4130 to any of the above materials for the same question
3. Finally 4130 to the same?
Thank you.
RE: Charpy impact testing requirements
I think you need to be careful with generalizing. As stanweld points out the API 5L materials fall under a different curve than the 106B. Curve A materials require impact testing at -20F at any thickness. As mentioned earlier 106B is exempt to 1/2" wall thickness but thicker schedules are not.
To my knowledge, 4130 isn't listed and therefore not exempt. Dissimilar welds require at least the HAZ to be tested for non exempt materials.
RE: Charpy impact testing requirements
1. 6010 and 7010 worst impact values (but good for -20F though)
2. 1" coupon the highest thickness I use and the one with the highest MDT meaning the worst case per thickness
3. No Post Weld Heat Treatment since PWHT increase impact properties
4. Althogh in curve B of Fig 323.2.2A, 1" has an MDT of 33F, I plan to test it at -20F (worst case)
if the above passes the Charpy, then I can write a verbage that indicates that the better conditions are good, also, most of our stuff are below 0.5" anyway.
Is this a fair idea? should I just do the Charpy on every coupon I welded...Please advice
Thank you.
As much as possible, do it right the first time...
RE: Charpy impact testing requirements
RE: Charpy impact testing requirements
RE: Charpy impact testing requirements
As much as possible, do it right the first time...
RE: Charpy impact testing requirements
Does that make sense or am I reading it wrong.
As much as possible, do it right the first time...
RE: Charpy impact testing requirements
API allows the manufacturer to establish a P-number grouging for materials not lited in ASME, section 9. See section 6, API-6A.
What type of equipment are you making? Spacer Spool?
Petrotrim Services
www.petrotrim.com
RE: Charpy impact testing requirements
API 5LX and A106 B fall under Curve A and B of Fig. 323.2.2A per Table A-1 respectively. As result the requirements of B3 in Table 323.2.2 apply to impact testing of the deposited weld metal and HAZ.
RE: Charpy impact testing requirements
does that mean that per table 323.2.2, the weld metal and HAZ (basically the welding) should only be impact tested only when MDT is below -20F right?
As much as possible, do it right the first time...
RE: Charpy impact testing requirements
RE: Charpy impact testing requirements
1. If I qualify my procedures with Charpy at -20 or whatever the MDT is set as, that the figure stated above for mateial apply, in other words, does higher thickness where the material MDT is higher than -20 pose a problem or is the welding of that pipe good for any thickness/
2. I have seen procedures with 6010 and 7010 for field stick welding, I don't think they'll be good for less than -20, can you recommend any good electrode for root and fill/cap for lower temperature
Thank you.
As much as possible, do it right the first time...
RE: Charpy impact testing requirements
You can make the root with GTAW with ER70S-2 or -6 and the fill passes with 7018 to easily meet -20 F, B31.3 impact requirements. You should also purchase your A-106 B and API 5LX pipe with -20 F impacts.
RE: Charpy impact testing requirements
If my MDT is -20F, i though the 6010 7010 comibation are qualified down to -20F for impact properties (absorbed energy ft-lb), can I not use those?
also, when I rule a straight line on the curve in figure 323.2.2A, the MDT for A106 ceases to be -20F at about 0.55 or higher, not 0.5. Is it generally considered 0.5 from a conservative stand point?
As much as possible, do it right the first time...
RE: Charpy impact testing requirements
Actually my doubt is on comment by Vesselfab(Sept 2011) that "don't forget that your weld consumables must be certified for -20F"
Is the requirement to be certified(Can be done by consumable manufacturer) or classified (expected to be classified by specification/standard/code)
As per UCS 67, weld is exepted from Impact test, if:
1. Material is exempted and
2. Welding consumable is classified by impact testing at a temperature not warmer than MDMT by applicable SFA specification.
Can any one guide me to how to find whether a given electrode/filler wire is classified by impact testing as above? (eg: ER70 S6, E7018, 80 S Ni1)I could see the following in the SFA5.1/18/28:
E7018-1 : Table 3 Charpy impact test requirements give a value of 27J@ -45 deg C
ER70S2 : Table 4 impact test requirements give a value of 27J@ -30 deg C
ER 80 S Ni1: Table 4 impact test requirements give a value of 27J@ -45 deg C
Does this mean that these consumables are classified by impact testing at a temperature (145, 130 deg C )as required by code(UCS 67)?
Thanks
Andy