This edition of the Fastener Training Minute with Carmen Vertullo was originally published April 22, 2018 as “Torque Wrenches, Finishing up” during episode 127 of Fully Threaded Radio.
Hi, it’s Carmen Vertullo with your Fastener Training Minute. Today, interestingly enough, coming to you from the Industrial Fasteners Institute in beautiful, Cleveland, Ohio. We’re getting ready to go to the Fastener show. It’ll be over by the time you hear this. I hope I saw you there and I hope you had a good time.
Anyway, as you know, we have been talking about torque wrenches lately, and we’re going to finish up that series today by giving you six different tips on dealing with torque wrenches, or helping your customers use torque wrenches. Just a few facts that everybody should know to keep them out of trouble when it comes to applying torque to your fasteners when we come back, we’ll talk about that.
Welcome back everybody. This is Carmen Vertullo with the Carver FACT Center and the Fastener Training Institute. We’re going to discuss six things about torque wrenches that you need to know. This is probably the minimum that everyone should know about torque wrenches, and this is how we’re going to finish up our series on torque wrenches.
First. So here we go starting with number one is the type of torque wrench. Choosing your torque wrench is very important. There are two primary types of torque wrenches, an indicating type and a control type. The indicating type tells you how much torque is applied. We typically we use the indicating type in the laboratory. The control type is the one that you use when you’re applying torque to a Fastener and you want to have a specific value of that torque applied. It’s important when you choose a torque wrench that you choose the right range; if the torque you want is a hundred foot pounds, you probably want to choose a torque wrench that maxes out about 200 foot pounds. Choose somewhere in the middle of the range. Buy the best tool that you can afford. Most torque wrenches have both units of measure inch in metric. But be sure that if you’re applying torque in the inch units of measure that you have an inch torque wrench and if it’s in the metric units of measure that you have that.
Second, this is probably the most important of the six I’m going to tell you is training. You cannot properly use a torque wrench unless you’ve been trained and torque is our friend as long as we know the tool and we understand how it works. So if you’re a supplier of fasteners and you want to get into supplying torque wrenches, you ought to be providing some training as well.
Third, take care of your torque wrench. That means you should store it properly. You should not use it or misuse it and don’t use it as a hammer or some other kind of wrench to disassemble your work and make sure you keep it in good calibration.
Fourth, always apply or read the torque when the wrench is in motion. That basically means don’t creep up on the desired number real close and then think you’re going to be able to get the correct reading when you’re pretty close to the end of the turning motion. You can maybe apply about 50% of the torque and then apply the rest so that your wrench is in full motion. If you hit the click or the buzzer goes off or the needle hits where it is supposed to hit the Pentagon what kind you are using
Fifth, the use of extensions. The standard extension that sticks straight out from the drive of the torque wrench perpendicular to it will have no impact on your torque value. So you don’t need to be concerned about that. But when you use some kind of a dog bone type extension or what’s called a crows foot extension in order to access a fastener that you wouldn’t normally be able to get to, that does affect the torque because it makes the torque wrench longer. There’s a little bit of math that goes into that calculation, but it’s not hard to figure out. However, it’s beyond the scope of this Training Minute. One thing that you can do though, if you’re using a crows foot and it’s not very long (less than an inch or two), just put it at 90° to the torque wrench and it will not affect your torque value.
Finally, Sixth. Be aware of which component you are tightening; whether it’s the nut or the bolt and what’s under that nut or bolt bearing surface. If you’re tightening the head of the bolt make sure the hardened washer is under the head, so you don’t mess up the torque tension relationship. And if you’re tightening the nut the same thing applies. Make sure you have a good bearing surface or a hardened washer under the nut.
Well, those were six tips to help you learn how to properly use a torque wrench, and if you’d like to have this in writing just contact the Carver FACT Center at www.carverfact.com, or go to our website. And let me know and I’ll be happy to send you a document on our little six tips on how to properly use torque wrenches.
This has been when Carmen Vertullo for the Fastener Training Institute. Thanks for listening.