The black art of boltingThe simple bolt is far from simple and each industry seems to build up its own ‘black art’ on how they are best used (plain washers, spring washers, two washers, drill and pin nuts, lubricate bolts, use Loctite on nuts, use two nuts one to lock the other, torque tighten, load indicating nut, part turn tighten, load indicating bolts…).

Of all the ExcelCalcs training modules I present the ‘Understanding Bolts’ module is often the most appreciated by attendees. The module seeks to replace the ‘black art’ with science to ensure that your bolts never loosen in service, break or fracture in fatigue. Take a day out to learn about bolts or contact me for a bolt training quotation. You’ll find lots of useful calculations on the ExcelCalcs site to help solve your bolting problems.

Repository News

FileUltimate shear capacity of bolt group.xlsBoltgroup01_YP.png
Yakov Polyakov is another 'spreadsheet king' and some of his many superb structural engineering spreadsheets are available for download on the ExcelCalcs site. One such calculation covers the instantaneous centre of rotation method to determine the ultimate shear capacity of bolt group. This method is described in LRFD Code (2nd Edition, Volume II, p. 8-28). The bolt group rotates around instantaneous centre, and the displacement of each bolt is proportional to the distance from the instantaneous centre. Yakov has many more calculations available from his own website - you'll find a link here.
FileStress in a rotating disk.xls

The solution of the classic problem of stress in a rotating elastic disk or cylinder, as solved in standard texts on elasticity theory.