Torque measurement of bottle screw caps

Torque force to open/close twist caps

Torsion, torque force or opening/closing force is the force required to open/close a bottle or other containers with a screw cap.

Importance of the right torque force

A cap torque tester or cap torque measuring system is required during the packaging design process.The cap should be sufficiently closing the bottle to make sure the content is not running out of the packaging, and on the other hand it should be easy to open.

In the food and beverage industry, the opening and closing torque of bottles and other containers with twist-off closures is an important quality parameter and vital for customer satisfaction.

The lower torque limit is considered the minimum pressure of the cap to avoid any leak of the product. This torque test needs to be combined with a leak test with secure seal analyzer. The higher torque limit is the maximum torque the customer can apply to open or close the product's cap.

Torque force measurement

The key to quality control of caps and closures is to imitate their opening action or actions in a repeatable way, and measure the torque forces involved.

Once torque tolerances have been defined, the cap torque tester is used as a torque control device on the final product. If measurements with torque measurement devices are out of the limits, the capping machine needs to be adjusted.

For many routine tests, where precise reproducibility, user independency and special test procedures are necessary, an automatic operated torque measuring device is an optimal solution.