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 Steel Pipe Deflection Post Reply Engineering Forum
 Posted by: gwc ® 07/21/2005, 11:16:35 Author Profile eMail author Edit Trying to determine what size/schedule of pipe to use. Currently using a 3" sch40 pipe 10 ft supported on both ends as a roller feeding a press. Two questions does anyone know the max force I can apply at the center with no deflection? How can I determine what size/schedule of pipe to use as I increase force to get zero deflection?I would assume that wall thickness would make a huge difference.Suggestions please!

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 Re: Steel Pipe Deflection : Steel Pipe Deflection -- gwc Post Reply Top of thread Engineering Forum
 Posted by: swearingen ® 07/21/2005, 18:09:24 Author Profile eMail author Edit First thing is first: there is ALWAYS deflection. ALWAYS. No exceptions. The question is how much deflection can you tolerate?Give us a target deflection and we can answer your other questions.And you're right - wall thickness makes a big difference.

 Re: Steel Pipe Deflection : Re: Steel Pipe Deflection -- swearingen Post Reply Top of thread Engineering Forum
 Posted by: sblack ® 07/29/2005, 16:32:49 Author Profile eMail author Edit He is right, you will have deflection. I ran some numbers to give you an idea of what your looking at, and the equation needed to solve this problem. Max. deflection at center with load at center= W*(l^3)/(48*E*I) Where: W=Weight, l=the whole length of pipe, E=Modulus of Elasticity, and I=Moment of Interia. Your answer will be the amount your pipe will bend at center, given in inches. You'll have to determine the weight, I used 1000lbs at center for an example. Using 3" pipe (actual O.D.=3.5") 10' long, the deflection at center for schedule 40, 80, and 160 (respectively) is .728", .5436", and .3954". Just take the equation and plug in numbers. P.S. The Modulus of Elasticity for pipe is about 29,842,202. Let me know if you need any more help.