Intermittent Weld 3

[dik]

I've generally used weld spacing of:
-FOR INTERMITTENT WELDS, LENGTH SHALL NOT BE LESS THAN THE GREATER OF 4 TIMES THE WELD SIZE OR 40MM. MAX CLEAR SPACING SHALL NOT EXCEED 12 TIMES THE THINNER OF THE TWO SECTIONS JOINED FOR JOINTS IN COMPRESSION AND 16 TIMES FOR JOINTS IN TENSION.

I recently came across the following:
-FOR INTERMITTENT WELDS, LENGTH SHALL NOT BE LESS THAN THE GREATER OF 4 TIMES THE WELD SIZE OR 40MM. MAX CLEAR SPACING SHALL NOT EXCEED 24 TIMES THE THINNER OF THE TWO SECTIONS JOINED (AWS D1.1 2004 2.11.2-1).

I don't know where the first spacing came from (I've always used it, but don't know the source), but the AWS stipulation allows a greater spacing. Is anyone familiar with the first criteria? and are there any caveats about using the second criteria as long as the weld is strong enough?

For an intermittent weld, 4@12 means 4" of fillet weld at 12" centre to centre of weld group; is my understanding correct?

Dik

 

[kingnero]

Don't know AWS, but for what it's worth, EN 2553 shows both weld length and clear spacing in the weld arrow (so not centre to centre) ... With the understanding that the last weld cannot be smaller than the stipulated individual weld length

 

[dik]

Thanks Kingnero, I was aware of the EN method, but understood AWS was the center to center spacing, not the clear distance. I'm on my own, and have no one around to ask. I usually double the weld length at the ends.

Dik

 

[JR97]

Dik,

You are correct. AWS A2.4 (standard symbols for welding) defines the intermittent weld callout as length-pitch. The pitch would be the spacing of the intermittent welds, generally center to center. When I have one to check, I set scale at pitch distance and check that there is 1/2 minimum weld length on each end of the pitch distance.

JR97

 

[kingnero]

@ dik, see attachment... centre-to-centre is correct.

 

[gtaw]

Years ago I received an official interpretation from AWS that stated regarding intermittent fillet welds that basically said the following:

The weld size specified is the minimum.
The weld length specified is the minimum.
The maximum unwelded space between adjacent welds is the pitch minus the weld length.
It makes no difference if you measure center to center, crater to crater, or beginning to the beginning of the next increment.

Best regards - Al

 

[dik]

Thanks, gentlemen... my problem came about because I was looking at intermittent welds for non static loading which was pretty restrictive. Got it sorted out... again, thanks.

Dik