Error Proofing By Design


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Error Proofing By Design Click Wrench




Torque related error proofing started with Walter P. Chrysler and Paul A.Sturtevant. That was 1924 and Mr. Chrysler was having problems with heads being unevenly torqued onto the aluminum block engines. Since there was no scale that determined "How tight is tight?" Chrysler invented the deflecting beam torque wrench. The heads on his aluminum block engines could now be tightened in a repeatable fashion. He licensed Paul Sturtevant to manufacture and sell the wrench. 

From the very first commercial torque wrench, the error-proofing industry was born. Since Beam Wrench - the original error proofing toolthen our engineers have worked within the context of "Error Proofing By Design". You can see the application of that concept across our line of products. We invented the first click wrench. What makes our wrench different is the flattened case. That flattened case was designed to reduce the human influence on torque application.  

Rounded beam torque wrenches are more flexible and they "sideload." In torque application and torque testing, the wrench is pulled at 90 degrees from the head. Any movement up for down from the 90-degree plane changes the torque calculation. Sideloading inhibits accuracy in the lab and on the shop floor. The flattened case prevents side loading. When the tool is designed to eliminate human influence and errors, that is error proofing by design

Our line of Micrometer Adjustable Torque Wrenches all have a flattened case. Our digital torque wrenches have a flattened case as well.  Of course, our preset click wrenches are designed with a flattened case. Customers say our digital torque wrench is as strong as our beam wrenches; just more accurate and it has a digital display on it. 


Frank Richmont, the founder of Livermont, invented the torque screwdriver. He also invented the limited-slip clutch that Cleco made an industry standard. From the beginning, our torque screwdrivers were engineered to be impervious to thrust load. When using a torque screwdriver thrust force must be applied as the driver turns. While thrust force may be applied in varying amounts depending on whether the application is overhead, at your feet, or somewhere in the middle the fastener can't be turned without keeping the bit in the slot. 


Thrust force changes the output of many torque screwdrivers. They may have one reading in cal lab and appear to be within tolerance. And, in the lab, they are. But get them into the production area and thrust force is applied and the readings in the cal lab couldn't be further from accurate. Thrust force changes the output on many torque screwdrivers. Our torque screwdrivers were all engineered to eliminate any impact of thrust force. While other torque screwdrivers lose accuracy and repeatability, in some cases our results get even better. Error Proofing By Design. 

We won't take you across our entire product line discussing how each tool is engineered for Error Proofing By Design, but any of our sales professionals can. 

Want More Error Proofing Information? 

Error Proofing By Behavior Modification - Through the Sturtevant Richmont integrated engineering design to eliminate the human influence in torque application and testing.

Error Proofing By Guidance - Tool design to eliminate human influence in the torque process is not enough. Today's intelligent tools are designed to provide operator guidance to create the best possible performance.

Error Proofing From A Different Angle: Definition of error proofing and some observations by W. Edwards Deming.

Finding The Balance: In error proofing "one size fits no one."  To find what fits in your organization, start with the fundamental question of "How much responsibility for error proofing should be given to the tool and how much should be operator responsibility?" This section provides more on this concept.

Six Error Proofing Scenarios: Error proofing solutions all have trade-offs. You can have control, or you can have flexibility. Rarely do you get both. This page looks at error proofing extremes as well as the middle ground.

How Much Are You Investing In Errors? If your current error proofing system or approach still leaves you with errors you are investing in errors, not error proofing. Error proofing is about quality, and it is also very much about dollars and common sense. This page digs into that.

Understanding The Common Centerline: Not having a common centerline is one invisible place where your error proofing approach can introduce errors instead of eliminating them. If you want to know how to calculate a common centerline and why it is important this page is for you.

There is more about error proofing in our tool pages. If you need more, your Sturtevant Richmont Sales Professional is a great resource to help. here.



 Sturtevant Richmont tools are proudly made in Carol Stream, Illinois by highly capable hands.