Maximum Weld Size for 1" plate connected to .465" HSS tube
Maximum Weld Size for 1" plate connected to .465" HSS tube
(OP)
Hello everyone,
I have a question which is kinda debatable. I have a 1" plate connected to HSS column with 0.465" thickness. The AISC specs says that the max weld size is 1/16 less than the plate size which in my case can go upto 15/16" weld size. In my analysis I need 1/2" weld but since my column thickness is less than the weld size is it OK to use it? I am not sure but can we use a weld which is larger than the base metal. Please provide me with a suggestion. A reference will be a bonus.
All you response is appreciated. Thank you in advance.
I have a question which is kinda debatable. I have a 1" plate connected to HSS column with 0.465" thickness. The AISC specs says that the max weld size is 1/16 less than the plate size which in my case can go upto 15/16" weld size. In my analysis I need 1/2" weld but since my column thickness is less than the weld size is it OK to use it? I am not sure but can we use a weld which is larger than the base metal. Please provide me with a suggestion. A reference will be a bonus.
All you response is appreciated. Thank you in advance.






RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
Mike McCann
MMC Engineering
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
The 1/16 requirement for plates 1/4 or larger is intended to give a way to visually observe the thickness of the weld. I believe the concern is that if you weld right to the edge of the plate that it is possible to melt the edge of the plate and give the illusion of a thicker weld. This requirement only applies when welding across the thickness of the plate.
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
For fillet welds at a right angle joint, the maximum available (well, useable) thickness is the thinner of the two wall thickness of the two metals being joined.
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
There is a limit on the unit stress to prevent over matching the filler metal. For example; in the case of a fillet weld, the unit stress in shear is .3 times the tensile strength of the filler metal, but the unit stress on the base metal must be less than .4 times the yield strength of the base metal.
Best regards - Al
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
Strength of fillet weld is Fw x Aw. Strength of base metal is Fy x Abm. If Fw is .7 x 70ksi = 42ksi and the tube Fy = 46 ksi you should be able to get a thicker weld than the base metal. The Aw for a fillet is also at .707 x tweld so you also get more effective base metal area.
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
You also would need to use strength reduction factor or omega for ASD as required, but concept is the same.
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
For now let say I have a tension of 65 kips.
Weld strength for 6" wide plate, using 1/2" fillet weld
= 0.928 x 8 x 6 x 1.5 (since load is at 90 degrees) = 66.816
Min thickness required = 3.09D/Fy = 3.09 x 8 / 46 = 0.537 which is less than the base metal thickness.
What else do I need to check, Please provide me some suggestions. thanks
https://gm1.ggpht.com/Jju-Xmk6wVgg6UxEOJE-SKvogCX1...
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
Best regards - Al
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
BA
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
Be conservative with welds. Check out AWS to see how undersize they can be for what length of weld. See some field 'welding'. And remember, members will warn you before they fail...connections will not.
ZCP
www.phoenix-engineer.com
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
Dik
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
Best regards - Al
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
https://www.flickr.com/photos/125092832@N03/145375...
at zcp, the size of the plate is 6" so I cannot get more weld length.
For now let say I have a tension of 65 kips.
Weld strength for 6" wide plate, using 1/2" fillet weld
= 0.928 x 8 x 6 x 1.5 (since load is at 90 degrees) = 66.816
Thank you for you help.
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
You don't seem to understand my previous concern: A simple fillet weld cannot be stronger than the thinner of the two plates joined at right angles. True, the thick fillet weld will not fail. It will pull out the wall of the vertical HSS out of shape, perhaps completely off of the vertical member.
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
The HSS wall is not capable of carrying the line load in bending, across the width of the HSS, so the bottom weld will tend to crack at the extremities which will then propagate toward the middle of the weld with a risk of premature failure.
The bearing at the top of the 1" plate is problematic too if the HSS wall cannot span across the 6" width so the force is delivered from plate to HSS by two concentrated reactions near the corner of the HSS. This could be mitigated by filling the gap with weld metal at each corner, but such a weld would require special procedures.
BA
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
Best regards - Al
RE: Maximum Weld Size for 1" plate connected to .465" HSS tube
what size is the Wbeam? why are you trying to make a moment connection here?
ZCP
www.phoenix-engineer.com