Kinex™ Bottle Capper Machines

An example of how the removal torque method works

We will use an example of a 28 mm cap being applied to a plastic bottle. From the Applications Torque chart you will see that the general application torque guideline for a 28 mm cap onto a plastic container is 13-17 inch.lbs. Within this application torque range, the cap will be properly seated onto the container and provide a high quality closure.

You will need to calibrate your capping machine to ensure you are providing the correct amount of application torque. The way this can be done is by using a bottle cap torque tester.

First we will find the correlation between the low end of the acceptable application torque range, 13 inch.lbs, and the correlating removal torque. Insert your bottle (always use new caps and containers for every trial when testing) into the torque tester and then tighten the cap by hand until the read out on the torque tester tells you that you have applied 13 inch.lbs. of torque. Then reset the torque tester and promptly unscrew the cap. When the cap releases from the threads of the container the bottle cap torque tester will provide you with the removal torque reading. Let’s say for example that the removal torque reading was 8 inch.lbs. We now know that for our particular cap, an application torque of 13 inch.lbs corresponds to a removal torque of 8 inch.lbs.

We will then follow the same procedure at the high end of the application torque range, 17 inch.lbs. For our hypothetical example say that an application torque of 17 inch.lbs results in a removal torque value of 12 inch.lbs. We now know that the application torque range of 13 – 17 inch.lbs correlates to a removal torque range of 8 – 12 inch.lbs.

We now begin to apply caps with the capping machine. After capping the container with the capper, we promptly bring the container with tightened cap over to the bottle cap torque tester and measure the removal torque. Let’s say on our first trial we receive a removal torque reading of 7 inch.lbs. Since 7 inch.lbs is lower than the acceptable range 8 – 12 inch.lbs., we know that the cap is not tight enough, so we will need to increase the torque setting on our capping machine. We will continue to adjust the torque output of the capping machine until we consistently receive removal torque values within the acceptable range of 8-12 inch.lbs. Our capping machine is now properly calibrated.