With good recycling properties, PET bottles have been used widely in the packaging industry. And, to make the things more environment friendly, many industries are now shifting their focus on creating light weighting of PET bottles, without compromising on the quality. Light weighting of bottles helps a lot in conserving the material used and thus reduced the overall cost of packaging.
The next challenge that is being faced is the light weighting of PET bottles to the extent that can withstand harsh transportation conditions because that is the main purpose of packaging. Thin walls, choke neck are some of the common areas that often create trouble for the manufacturers. Thus it is very important to maintain a desired and consistent thickness of the bottle, that can bear compressive buckling load.
Wall thickness gauging is the process that is incorporated into the manufacturing cycle to maintain a consistent wall thickness. There are number of wall thickness gauging tests for this. The most common used method used is to cut the bottle into different part and measuring the thickness of each and every portion that is cut.
Why destructive method of testing cannot be used every time?
A PET bottle cannot be cut into pieces every time for its testing. This is why manufacturers have started using alternate methods for wall thickness gauge testing. With Hall Effect testing, the destruction of bottle can be avoided while getting the accurate results as per quality standards.
What is Hall Effect Testing?
Hall effect : If a current carrying conductor is placed in the magnetic field, it produces a difference in voltage in perpendicular to the flow of current.
Magnamike 8600 works on this principle and very easy-to-use testing instrument. It has a magnetic probe and a ball which is kept inside the bottle. The hall effect sensor, the probe and the ball, create a magnetic field proportional to the thickness of the bottles walls to create the difference in voltage. This voltage is processed and displayed on the screen in digital format.
It accurately measures the thickness of the walls and store them on a removable micro SD card. With this testing instrument, the thickness of preforms can also be measured.
In this attempt of light weighting of PET bottles, it has to be ensured that PET bottles are passing all other quality standards e.g. Buckling load testing, tensile testing, bottle burst testing.
Apart from PET bottles, this instrument can be used for other non-ferrous materials like aluminum cans, glass bottles, water tanks, etc.