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Thanks Tmoose, I have a pic of what the loading and padeye orientation looks like. How can the pic be attached to my reply to this post? Tony Billeaud Mechanical Engineer

I've got a padeye welded to square tubing that has a 1/4" wall. Load on padeye is parallel to the axis of the tubing. I am trying to find out if there is a standard way to check the stresses in the tubing if the load on the padeye puts a moment into the weld at the base of the padeye. The...

Can anyone direct me to a reference/website that would give some helpful information on selecting abridge beam and runway beam for a bridge crane. I will be purchasing the crane end trucks but I need to design the bridge beam and the runway beam. I can design the I-beams based on the hoist...

Has anyone used the "C" shaped pipe hooks for lifting pipe. We have some from both Newco and Rigmaster. Newco has indicated that the SWL of the hooks is based on a sling angle of 30 deg. (included angle from horizontal). Rigmaster's SWL is based on a 45 deg. angle. Does anyone have experience...

In a previous closed thread (thread404-81231), "Superstress" suggested to use the approach outlined by Bruhn when checking stresses on a the pin an a lug clevis assembly. Does anyone know if using this analysis would be a conservative approach or if it is a close approximation of the actual...

Vonlueke, Can you provide any info on the orgin or derivation of the formula you have provided? If the top of the beam is horizontal and only the bottom has the taper then the height of the base would need to be no taller than twice the height of the beam at the tip - correct? Thanks, Tony...

Should the shear stress at the base of a lift eye (padeye) be calculated using the average shear stress formula or the transverse shear stress formula (sress=1.5*(V/A)) for a rectangular section? The padeye has transverse loading in the plane of the padeye. Thanks in advance for any help with...

I uncovered something that I may have overlooked in past design calculations. The question comes up when analyzing the stresses on a tapered padeye (with a long base to hole dimension) or on a tapered beam. The tapered member is loaded perpendicular to the longitudinal axis of the member. For...

I need to come up with a design for equipment that will automatically move joints of pipe down a set of pipe racks and stop at required positions. We have two pipe racks spaced 24' apart. The joints of pipe are anywhere between 30' to 40' long and are between 20" to 48" in diameter. They need...

Can anyone give some feedback on what pressure is assumed when a coefficient of friction is listed for oak (or wood) on steel in various tables that are available. The friction coeficients that I have found for oak (or wood) on steel have all been in the range of 0.2 to 0.6. For my current...

Thanks to all for the input to this problem. It has been a hectic 2 months and I have not been able to respond till now. The weight of 43.7 kips that I listed in the original post corresponds to a 36" diameter x 2" wall x 60' length (not 30" x 1 1/2" as originally indicated). The yield...

I'm ashamed to say that it's been a long time since I have needed to solve any dynamics problems but I now have one that I am stumped with. Can anyone help? I have a joint of A-36 pipe that is sitting on 2 A-500 GrB tubing racks. The outside dimeter of the pipe will be pushed with an arm (at...

Thanks to all who responded. desertfox, The spreader bar is rated to lift 65,000# and is designed wih a safety factor of 4.0. Fatigue is not an issue for this spreader bar. I had considered the offset buckling load. I was originally considering making the padeye plate an "angle" shape with...

Desertfox, Thanks again. You did not comment on any local buckling that might be present near the padeye welds. Should this be checked with some assumption made with regard to the local bending or buckling in the pipe? Thanks, Tony Billeaud Mechanical Engineer Franks Casing Crew

Thanks Desertfox, The pipe is 12" sch 40 or 80 (not decided yet). The padeye plate is 2" x 7" A-36 flat bar or plate. The padeye plate is oriented at a 45 deg angle relative to the spreader bar. As I described before, the padeye plate is slid through slots that will be cut into the 12" pipe...

Thanks Cockroach, I have already analyzed the pipe for buckling using the AISC ASD formulas. I am now only concerned with any local buckling or bearing that the pipe would see in the vicinity of the padeye/plate. Thanks again, Tony Billeaud Mechanical Engineer Franks Casing Crew

Can anyone help - I am designing a spreader bar and will be using pipe as the spreader bar. The padeyes on the top and bottom of the spreader bar will be made of one piece of flat bar that slides through the pipe and is welded to the walls of the pipe. I have checked the buckling in the pipe...

Desertfox, I have a large pin in a hole near the edge of a plate and the force on the pin is pulling the pin towards the edge of the plate. I was only suggesting that the 1.5*D distance to the edge of the plate could be much larger than needed if the hole was very large based on the pin...

Thanks again for the help. Desertfox, What if the hole was very large in order to accept a large pin that was required to resist bending. Would the rule of thumb of placing the center of the hole 1.5*D from the edge still apply in that case? It seems that it would be too large a distance...

Thanks to all who have helped with this question. Cory, How would you check for plate fracture? Thanks, Tony Billeaud Mechanical Engineer Franks Casing Crew