Every bolt has a torque value or specification that is calculated to prevent bolt failure and help ensure the reliability, quality, and safety of the product or structure in question. It is important to know how to measure torque on a bolt to verify that the bolt torque value specified is accurate. At Peak innovations Engineering, we offer an extensive array of bolt torque testing services to ensure your industrial applications function properly and at peak performance.
A bolt that is not fastened properly according to the recommended torque value provided by the manufacturer or third-party bolt tester can result in fastener thread stripping (due to excess torque) and bolt loosening and removal (due to repeated vibration).
Whether the bolt you are using is a lag bolt, hex head bolt, carriage bolt, or tap bolt, before the product is approved for use, it must undergo proper testing and receive verification. The ISO 9001 standard specifies torque values that are expected of different types of bolts.
If you want to know how to measure torque on a bolt. Here are a few common ways:
Marking Method
Once the bolt is tightened, the surface of the bolt and of the workpiece or product are marked. The bolt is then loosened. Next, it is tightened until the marks made are realigned. The torque value of the bolt is the amount of torque required to bring the bolt back to its original position.
Movement Method
Once the bolt is tightened, the bolt and workpiece/product are marked off with a torque measuring tool. Then, additional force is applied in the direction of tightening until bolt movement is seen. The torque reading at that moment is the residual torque initially applied to the bolted joint.
Loosening Method
This method of measuring bolt torque is similar to the movement method except that extra force is imposed on the tightened bolt in the direction of loosening. The torque reading at the moment the bolt breaks loose is the torque initially applied to the bolted joint.
When to Determine Bolt Torque
It is important to find and record torque values immediately after bolt tightening and before the product or structure is heated or painted. If the bolt is left to stand for too long or subjected to certain environmental conditions, the friction in the bolt threads and under nut surfaces which affects the accuracy of readings will be changed. This will result in an inaccurate torque reading.
Contact Us for Bolt Torque Testing Services
Our team at Peak innovations Engineering knows how to measure torque on a bolt and test bolts and other fasteners for various performance capabilities. To learn about our bolt testing services, give us a call today at 815.420.3802 or complete our contact form.
