Washers serve an important function to spread the load out under the nut or the head of a screw or bolt
This edition of the Fastener Training Minute with Carmen Vertullo was originally published February 12, 2015 as “Washers: Use and Misuse” during episode 90 of Fully Threaded Radio.
Washers seem to be relatively simple animals. They’ve got no threads. They’ve got a hole. They’ve got an inside and outside diameter, and a thickness. And if it’s a lock washer, it’s got some other things going on. There is a lot more to know about washers than you ever thought and a lot of money to be made selling them.
If you are in the fastener business, chances are washers are one of the non-threaded accessories you provide. Washers serve an important function. They serve to spread the load out, under the nut or the head of a screw or bolt. They make things look nice and pretty. They make it so we can bolt softer materials together with hard and strong fasteners. But washers are often misused. We sometimes use a soft one when we should use a hard one. Sometimes we use a lock washer when it does no earthly good. And a lot of times, we just flat out spend too much money using the wrong washer.
Standard washers dimensionally come out of a standard called ASME B 18.21.1. That’s in your IFI 9th edition. Hardened washers are used with structural bolts and some other applications, and come from ASTM F436, that’s also in your IFI 8th and 9th editions. And ASTM F2437 are direct tension indicating washers, and we don’t really want to use the word washer, they’re direct tension indicators for use in structural applications.
Those are just a few of the things we talk about during our Fastener Training Institute webinars on washers. So if you are in the business of selling washers, join us for the next one. You can see our schedule of webinars at www.fastenertraining.org.