Torque measurement is utilized in three areas of assembly. Controlling torque is quintessential for companies to ensure their product’s quality, safety and reliability isn’t compromised.
Prior to Assembly
Torque testing equipment, like electronic torque tester and torque sensors are used before assembly process for tool setup or conducting tool capability studies. For tool setup, the tool crib will want to set the torque tool according the torque specification required for the application. For tool capability studies, technicians need to ensure that the torque tool can provide the necessary torque and repeatability that’s required for a potential application.
The equipment used for this torque testing would be:
– Tabletop torque testers with built-in transducers
– Torque analyzer that connects with either stationary torque sensors or rotary torque sensors
– Joint simulators like run down adapters
During Assembly
For air and electric assembly tools once the torque tool is being used in the production area, many manufacturers like to audit the tool and verify the actual torque being applied to the application or if the tool is starting to fall out of specification. The Rotary Torque Sensor is the ideal torque-auditing tool for testing the actual torque being applied on the assembly application. By connecting a rotary torque sensor between an electric or pneumatic tool and assembly application, you can monitor the torque being applied from the tool to fastener or bolt. This type of torque reading is called a dynamic torque reading. The rotary sensor is connected to torque analyzer, which records and stores the data.
Manufactures also use this auditing process finalize the torque setting of the tool and to confirm process capability. Since each application has a different joint rate and tolerances, the performance of the tool on the application may differ from the tool crib results. Using a rotary sensor connected to a torque analyzer, technicians can take these differences into account and make any necessary adjustments.
After Assembly
As a final check, manufacturers may select to verify residual torque. By measuring torque after the assembly, you not only verify adequate torque was delivered to the fastener, but may also detect missed or loose fasteners, or joint relaxation. But since the application is already seated and friction during rundown is different than the friction in a static joint, the torque measurement will vary from those in the tool crib and from the dynamic values. These differences will need to be accounted for when engineering a residual torque specification.
The equipment used for conducting testing would be:
– Dial Wrenches and Dial Screwdrivers
– Digital torque wrenches
– Wrench or screwdriver sensors mated with a torque analyzer
