How to specify a patterned Plug Weld on drwg 2

[Jamziee]

Hi all,

I want to use a plug weld symbol on a drawing. Referring to the ISO standard, it states that the symbol has the dia of the plug before the symbol, with the dimensions (qty x pitch) following the symbol.

This is fine for a set of plug welds in a line, but what if you had a pattern of them?

Many thanks,

Andy.


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(Using: UG NX6)
Design Engineer

 

[MintJulep]

Pattern = ?

Grid, checker board, spiral, circle, paisley, houndstooth, something else?

 

[racookpe1978]

With as many "low quality" and new workers and supervisors out there as there are today, do NOT assume even your "technically correct" plug weld symbol is going to be fabricated correctly.

Draw the pattern in CAD (at least the first 4 - 5 rows and columns) and dimension the holes and the spacing you want. Draw the OTHER END as well - Today's youngsters won't know where to stop either. Then add "Typical Plug Weld. Grind Flush."

 

[KootK]

Agree with racookpe. If's reasonably simple, you might get by with a bare bones inset detail.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[berkshire]

racookpe,
Is the grind flush instruction to ensure they have filled the plug weld to the top?
B.E.

You are judged not by what you know, but by what you can do.

 

[dhengr]

Berkshire:
The “grind flush” note is so they will grind the parent metal down to whatever the min. plug weld the welder felt like making and leaving. This makes it look real purty.

Otherwise, the actual plug pattern is determined, sized and dimensioned on a part detail, so the holes can be drilled, punched or cut in the base metal piece. Then, the weld symbol shows how these holes are to be plug welded. The holes might be filled and ground flush, and on larger holes a fillet (size to be determined) all around might be all the weld that is needed. Plug welds are not very reliable welds because it is hard to be sure the welder has gotten a good weld at the root, btwn. the two pieced of base metal, or even up the vert. leg on the second pass. The hole should be at least (1.25)(base metal thickness) so they can get into the root properly for welding.

 

[berkshire]

Dhengr,

The hole should be at least (1.25)(base metal thickness) so they can get into the root properly for welding.
No kidding, the number of times I have checked plug welds to find only half of the root actually welded, and a slag puddle in the other half is without number.
B.E.

You are judged not by what you know, but by what you can do.

 

[gtaw]

When in doubt, sketch it out!

Standard welding symbols are adeguate for 90% of the welds used by industry, but with the remaining 10%, use a sketch.

Best regards - Al

 

[Jamziee]

Hi all,

Many thanks for your responses. The positions of the plug welds are actually called out on the piece parts before assembly (i.e. hole positions). So I can simply call out the weld symbol with stripped down information.

You've also answered another question where we have a simple 3 spot weld pattern on an assembly. So for this, I'll show the positions and size of the spot welds dimensionally and so the the weld symbol can be shown without the size & pitch. This is what I was thinking initially, so I feel a bit happier now.

Many thanks.

Andy.

---------------------
(Using: UG NX6)
Design Engineer