It is no surprise that adding torque testers to the tool crib or on the shop floor and implementing a rigorous testing schedule is a commonly used quality strategy. What is a surprise is the number of mistakes we see being made in the field as we work with companies doing in house testing of torque wrenches. Here is a list of the most common issues we see and how to avoid them. 1. When testing a click type wrench, exercise the wrench by clicking it at least five times prior to testing. Why? Think of it as warming up or stretching before you exercise. The measuring element in a click wrench is the spring. When the wrench has not been used the spring will take a set and that will affect the accuracy of the wrench. Also lubricant used inside the wrench can “set up” or “settle” so moving the internal parts minimizes the effect this can have during testing. 2. Use as few adapters (none is best) as possible between the wrench and tester. Why? Adapters introduce significant variability into the testing process with the biggest being not applying force at 90 degrees and that affects the accuracy of both the wrench and tester. 3. The capacity of the wrench being tested should fall within the middle 75% of the testers range. Why? It is the same reason you cannot use a bathroom scale to weigh the mail or that same scale to weigh your car. 4. Make sure the head of the wrench is not touching the tester. Why? An interchangeable head or ratchet contacting the tester will create friction causing inaccurate test readings. 5. When testing an interchangeable head wrench or one being used with an adapter, use the same length head or adapter as that used on the production line. Why? Torque = Force X Distance, change the length and you change the torque output of the wrench. 6. If you are testing a wrench by hand make sure you are applying the force evenly on the grip and ensure that the team out on the assembly line is doing the same thing. Why? Applying force towards the front or back of the grip can influence the torque output of the wrench. 7. Make sure your power supply is stable, the tester is properly grounded and static electricity is eliminated during testing. Why? All of the above can interfere with the sensitive electronic circuitry of the tester to accurately measure. 8. If you are testing a click type wrench, “initial” or “first” peak mode should be used. Why? These click modes measure the wrench mechanism while peak mode measures the response time of the operator. 9. Regularly calibrate and certify your tester, preferably using an ISO/IEC 17025 certified laboratory. Why? Common sense tells you that torque wrenches calibrated on an out of spec tester defeats all you are trying to accomplish. Regularly testing your wrenches helps identify issues by finding that certain locations or employees require constant recalibration or repairs. You can also develop a value/cost analysis for torque wrench purchases based on which brand is more durable or holds calibration longer than others. Follow the guidelines above and gain confidence and control of your in house torque wrench-testing program. For more information about the new Torq-Tronics 2® torque tester go to www.srtorque.com or email us at email@example.com Sturtevant Richmont Your Quality is Our Business. The company that invented the torque tester has re-invented it! Introducing the new Torq-Tronics 2®. Accuracy of +/- .5% of Indicated Value from 10% to 100% • Tests in both clockwise and counterclockwise directions. • Four modes of operation - Track, Peak, Initial Peak and Power Tool - provide excellent versatility. • Units of measure include English, Standard International and metric. • Units of 300 inch-pound (34 Nm) capacity and below are optimized for bench mounting; larger units may be mounted vertically or horizontally. • With only 8 buttons Torq-Tronics 2® is amazingly simple to operate! • Electronics module with large VDF display is easy to read in any lighting. • Serial port or USB for output of test results to computer or laptop - immediate documentation of test results! • Auto-clear and auto-print functions are built in for ease of operation and recording results. • Red/Green LED indicates whether a measurement is within the target torque value percent accuracy calculation (green) or over target torque value percent accuracy calculation (red). • Overload (106% of capacity) warning light is built in and all torque readings are recorded, even in overload situations. • When used with Torque Tool Manager Software, NISTtraceable certifications can be created to meet ISO and QS requirements. • Includes FREE certificate of calibration from our ISO/ IEC 17025 Accredited Calibration Laboratory! • Includes 120-240 VAC to 6 VDC convertor, and Quik- Guide instructions. • Runs on four NiMH rechargeable batteries. • Stores up to 999 readings. • Includes a free blow molded plastic box for storage and transit. • Power Tool mode has ten filters and will accurately test all clutch type and pulse tools. For more information visit www.srtorque.com 555 Kimberly Drive Carol Stream, Illinois 60188 In US: 800.877.1347 Outside US: 1.847.455.8677 www.srtorque.com firstname.lastname@example.org
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