Ring pull problems get analysed
The company’s experts have developed a rig that allows makers of food tins and drinks cans to measure the force needed to lift the ring pull and open the container.
Understanding and quantifying the force needed to use a ring pull is vital for both packaging manufacturers and their customers to ensure safety, functionality and consumer experience.
The force required to open tins and cans is dictated by the shape of the ring pull and lid, their materials and the depth of the groove in the lid.
However, until now, only subjective methods were available for assessing ‘force to pull’, which made it difficult to identify the design that provided both ease of use and packaging integrity.
The new rig works by locking the product in place on a TA.XTPlus texture analyser and attaching a hook adapter to its ring pull. The hook is pulled upwards, mimicking the action of a person opening the can, while measuring the force needed to lift the ring pull and finally break the seal.
The universal design of the ring pull rig means non-circular shapes, such as meat or fish cans, can also be analysed.
Exponent software enabled the development of a test for tins that require a two-step pulling action. The rig first measures the force needed to break the seal before pausing and allowing the user to adjust the hook direction or rotate the tin.
The second part of the test then measures the force required to peel and remove the metal lid completely.
Contact: Stable Micro Systems