×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

How to determine Lateral torsional loading

How to determine Lateral torsional loading

How to determine Lateral torsional loading

(OP)
I am currently working on a drilling project which plans to use a steel template subsea to accurately locate well locations on the seabed.

The steel template is to consist of four cylinders (1m dia with 25.4mm wall thickness and 1m in height)interconnected with a universal beam (serial size 0.914m x 0.419m).  The four cylinders will be spaced out equidistant from each other at 4m intervals. Overall length of the assembly is 12m.

The assembly is to be supported at one end and therefore will act like a cantilever.

It is planned to pass rotating components through the cylinders in a vertical direction and there is a possibility due to the tight tolerance that they could bind on the cylinder creating a torsional load in the horizontal plane of the assembly.

Question is will the torque be transmitted directly to the suppport at the end of the cantilever or will it have to overcome the weight of the assembly from the point of torsional loading to the cantilever support?

Hope this wasn't too confusing.  Thanks for any help

Rgds

Bogster

RE: How to determine Lateral torsional loading

As long as the binding action at one side pushes downwards and upwards and is eccentric it will generate some amount of torsion in the cantilevered beam, the amount of which maybe is to be estimated through structural analysis of the whole 3D contraption (schematic, i.e., lime members) and likely by imposed deformations caused by the drilling equipment, the actual expected the better if known, if not an estimate.

Of course for a detailed analysis you will count the selfweight of the structure, but since this (other than the attached cylinders maybe) is centered it means no thing to counterbalance any imposed torsion.

So it is a matter of taking the efforts produced by the analysis and verify all is OK, or else change again.

RE: How to determine Lateral torsional loading

Hi Bogster

If I understand correctly your set up ie:- 4 cylinders in a straight line connect by a universal "I" beam ?

I would just raise the point that "I" beams are not very good with torsional loads and a better shape would be a closed section like a tube , rectangle or square. In response to your question, shear stress due to torsion would be present along the beam length and maximum deflection would occur at the point furthest from the support.

As these tubes your supporting on a cantilever are quite heavy have you allowed for the vertical deflection of the cylinders due to self weight when determining clearance for the rotating components to pass through the bores?


regards desertfox

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources