ASME fillet weld size tolerance 1

[weldgal]

According to the foreword in ASME Section VIII, "the Code does not fully address tolerances. When dimensions, sizes, or other parameters are not specified with tolerances, the values of these parameters are considered nominal and allowable tolerances or local variances may be considered acceptable when based on engineering judgment and standard practices as determined by the designer". I'm looking to establish a company-wide "standard practice" for evaluating the acceptability of undersized fillet welds. I've researched the internet, AWS, TWI, among others. Does anyone have any suggestions?

 

[weldtek]

I'm not sure of your application, but, have you reviewed AWS D1.1, Table 6.1?

 

[weldgal]

I have, and I'm probably going to base our own standard around it.

 

[nickelkid]

You may find the attached of interest

 

[JoeTank]

A long time ago I had to resolve numerous cases of undersized fillet welds on pressure vessels and heat exchangers built to ASME Section VIII. After thrashing around for a while I found exacltly what I wanted in ASME Section III. I do not recall the section and paragraph and do not have a copy available to me anymore. Check it out.

Joe Tank

 

[weldtek]

If you're talking about ASME work, I'd suggest that you take into consideration the engineers calculations

 

[weldgal]

JoeTank: While I don't have ASME-III in my library, I'll see what I can find; thanks for the suggestion.

weldtek: The standard I'm writing will apply to ASME work (since AWS already addresses undersized fillets). And while my Code calcs usually do provide the min weld size required, they don't always (if I'm building a non-pressure unstamped unit in accordance with VIII-1), so I want to have a company-wide standard that will provide a consistent means to evaluate the acceptability of undersized fillets.

 

[JoeTank]

weldgal,
By memory (and it's getting weak these days) the size tolerance was 1/16" low for no more that 10% of the weld length. Just a reminder, ASME minimum weld sizes are based on throat, not leg size. An undersized leg will often have adequate strength if the throat is convex.

Joe Tank

 

[doct9960]

weldgal,

EPRI's NP-5380 (Visual Weld Acceptance Criteria) is a standard for evaluating structural welds in nuclear power plants. The document is free to download and publicly available...

http://my.epri.com/portal/server.pt...D=NP-5380-V1-V3(SET)&RaiseDocType=Abstract_id

 

[JohnBreen]

http://my.epri.com/portal/server.pt...D=NP-5380-V1-V3(SET)&RaiseDocType=Abstract_id

ERROR:
Invalid Document Download Request.
at EPRIDocumentAccess.ProcessDocumentRequest.Page_Load(Object sender, EventArgs e) in D:\Inetpub\

http://wwwroot\EPRIDocumentAccess\ProcessDocumentRequest.aspx.cs:line

124EPRIDocumentAccess

 

[doct9960]

The link was working this morning and I was able to download the document. What you can also do is go to the EPRI website (

http://www.epri.com)

and do a search. On the upper right corner of the webpage, do a search on the EPRI.com and type "Visual Weld Acceptance Criteria" (including the quotation marks) on the search box. The document should be rank #5 on the list.

 

[doct9960]

http://mydocs.epri.com/docs/public/NP-5380-V1-V3(SET).pdf

 

[GenB]

rule for minimums? use minimums per UW-61 and 62
but you will have to always adjust for requirements of pressure, temp, thickness? corrosion allowances when required when welds inside or pressure side.
you can not just have one size fits all, 'sorry