Clamping force on a bolted joint

[s2btsull]

Given the initial torque ( in lb ) imparted upon a UNC 4-40x 1/2 Type II Cross Recessed Pan Head machine screw and nut, how can I figure out the clamping force imposed upon the bolted joint? I have the equations to find the bolt preload given an initial torque, but not the clamping force. To add insult to injury, the screw/bolt system has several bushings in it. Is this something that I need to consider when determining the actual compressive force on the bolted joint? Lastly, I have heard mention of a book called the "bolting bible"; does anybody know of this book or where it can purchased?

 

[jobeth]

Check out <A HREF="

http://www.boltscience.com"

TARGET="_new">

http://www.boltscience.com</A>

<p>William H. Bernhart, P.E.<br><a href=mailto: > </a><br><a href= > </a><br>I work as a development engineer for AMP - Tyco Electronics located near Harrisburg, PA. I help design interconnections and electrical connectors for aerospace applications.

 

I work at Rotek Inc. in Aurora Ohio and this is<br>a common problem to large bearings which are bolted<br>in place.&nbsp;&nbsp;The clamping force, turning angle, torque<br>are related to the rated tensile strength of these<br>bolts posted by most bolt manufacturer's.<br>They are generally posted by the grade of bolt, material,<br>etc.

 

[DonLeffingwellPE]

I think you need to look at a good machine design textbook.<br><br>&quot;Machine Design-Theory and Practice&quot; Deutchman, Michels, and Wilson<br><br>&quot;Mechanical Engineering Design&quot; Shigley and Mitchell<br><br>&quot;Design of Machine Elements&quot; Spotts<br><br>Or you might try the Machinery Handbook by Industrial Press Inc<br><br>The clamping force will also depend on the materials being clamped in a bolted<br>connection.<br><br>Don Leffingwell<br><A HREF="mailto:dleffingwell@snet.net">dleffingwell@snet.net</A>