Longer, Smaller Size Fillet Welds Reduce Costs
Jun 21, 2006, Omer W. BlodgettOmar Blodgett (left) with co-workers at the Globe Shipbuilding Co. shipyard in 1945. For a given strength of weld metal, the capacity of a fillet weld...
Weld Orientation Has Consequences
May 19, 2006, Omer W. BlodgettExperience and experimentation have shown that the orientation of a fillet weld with respect to the direction of loading affects the joint's strength....
Understanding Bend Tests
Mar 21, 2006, Omer W. BlodgettFigure 1: In a bend test, a flat strap of metal is bent into a U-shape, stretching the material on the outer surface of the "U," while compressing the...
What don't you want the worst?
Oct 17, 2005Omer W. Blodgett, Sc.D., P.E. Heat exchanger assembly. More movement horizontally could result in a wavy weld. More movement vertically could affect the...
Understanding Material Properties: Stiffness
Sep 13, 2005Grinder operators keep spark streams away from persons and flammables. Today's welders producie quality, precise welds needing less material removal....
Understanding Material Properties: Stiffness
Sep 13, 2005, Omer W. BlodgettAs odd as it seems, engineers sometimes misunderstand the role of material properties. In attempting to solve a problem, they often seek a stronger material...
Check Your Drawings for "See Me's"
Aug 1, 2005It was a simple concept for a sturdy motor platform: four pieces of C8X10.5 channel made up the base. Two lengths of 1-in. thick steel, measuring 5 X...
Look beyond the failure
Jul 1, 2005, Omer W. BlodgettWhen analyzing the reason for the failure of a welded connection, it's important to look in the right place. It is easy to become fixated on a cracked...
Listen to the welder
Jun 1, 2005, Omer W. BlodgettAn engineer carefully designed the welded assembly for the lifting bail of a machine. On his drawing, everything fit fine. But on the shop floor, the...
Don't design by tradition
May 1, 2005, Omer W. BlodgettOmer W. Blodgett, Sc.D., P.E. When new designs are considered, blindly following tradition can lead to problems. While it may be very tempting to build...
Using gussets and other stiffeners correctly
Apr 1, 2005, Omer W. BlodgettBy Omer W. Blodgett, Sc.D., P.E. Gussets are triangular stiffeners or brackets added to members that intersect at roughly right angles. For some designs,...
Watch out for elastic loading
Mar 1, 2005, Omer W. BlodgettOmer W. Blodgett, Sc.D., P.E. How large must a weld be when no load is transferred between the two parts? If it is re-ally true that "no load" is transferred,...
Avoid introducing constraint
Feb 1, 2005, Omer W. BlodgettOmer W. Blodgett, Sc.D., P.E. Any design engineer or manufacturer dreads the following scenario: A new system is installed at a customer's facility, and...
Find the source of the problem
Nov 1, 2004, By: Omer W. BlodgettWhen it comes to fixing welding problems, engineers and manufacturers occasionally find themselves in a position where appearances are deceiving....
Provide proper support for welds
Oct 1, 2004, Omer W. BlodgettA lug 4-in. long, 5-in. high, and 1-in. thick attaches to the beam flange. Through a hole in the lug, the hydraulic cylinder applies a force of 22 ton,...
