Fillet Weld Size - Rule of Thumb
Fillet Weld Size - Rule of Thumb
(OP)
I recall somewhere that there is a rule-of-thumb for the size of fillet welds. It is something along the lines of half the thickness of the thinnest member being welded. Or was it twice the thickness of the thinnest member being welded?
Can anyone clarify this for me?
TIA,
--Scott
Can anyone clarify this for me?
TIA,
--Scott
RE: Fillet Weld Size - Rule of Thumb
RE: Fillet Weld Size - Rule of Thumb
"(a) for full strength welds, the leg of the fillet weld must be about 75% of the plate thickness."
Here is my take for double fillet welded joints
The effective throat of an equal leg fillet weld is .707 x leg size. .707 x .75t = about .53t. 2 equal leg fillet welds with leg sizes of 75% the thickness of the base metal would result in a fillet weld with an effective throat of 1.06t.
Good day
RE: Fillet Weld Size - Rule of Thumb
I'll look through Blodgett's (Lincoln Press') Design of Welded Structures again to verify this. I figured this information was in there, but couldn't find it.
--Scott
RE: Fillet Weld Size - Rule of Thumb
Thinnest Fillet
Member Weld Size
----------------------
1/8 1/8
3/16 3/16
1/4 1/4
3/8 1/4
1/2 3/8
5/8 3/8
3/4 3/8
7/8 1/2
1 1/2
1-1/4 1/2
1-1/2 3/4
2 3/4
RE: Fillet Weld Size - Rule of Thumb
Table 5.8
Base Metal Thickness Min. fillet size
T= <1/4" 1/8"
1/4"~1/2" 3/16"
<1/2"~3/4" 1/4"
3/4" plus 5/16"
*** leg size need not be greater than the thinner of the two parts joined.
refer to 2.4.5 and find maximum fillet weld size...
(1) for base materials 1/4" or less full plate thickness
(2) 1/16" less than the base metal thickness, unless the weld is designated to be built out to obtain full throat thickness.
hope this helps....
Richard Schram
Mechanical Integrity Specialist
Pharmacia Global Supply Arecibo-P. Rico
rschram@pharmacia.com