When a PET bottle is manufactured, it is made to pass a variety of parameters before using in real life conditions. The major properties that define the quality of bottle are its stability, balancing, even thickness and leak proofing. There are prime factors that a layman understands while investigating a bottle.
All properties are tested after the bottle is blown moulded. When tested for different properties, usually destructive tests are performed for assessment. Sectional measurement plays a crucial role in determining various things. A bottle is usually identified in 3 parts; Neck, Main Body and Bottom. The first job of operator is to precisely cut the bottle into 3 sections. This is tricky, if done manually. For perfect cutting, hot wire bottle cutter is used.
This machine is an assembly having a heating unit on one side. It has a frame having two wires attached to it. This frame is fixed from one side and another side is used to pass the wires through the bottle. It has a clamping mechanism to hold the bottle for avoiding any slippage. The size of bottle that can be tested is 200 ml to 2 litres. The wires are heated to cut the bottle into sections. The best part about this cutter is that it does not deform the bottle, not even the slightest of the deformity. Presto offers 2 configurations for this device, 2 wires and 3 wires, depending upon the requirement.
Importance of Determining Sectional Weight
For perfect balancing bottle, the weight of every section is defined and predetermined. This is very important when aesthetics come into consideration. The bottle should be beautiful, strong and well balanced, this is what every packager demands. Using a hot wire cutter, the operator gets three important sections of the bottle. Each of them is weighed separately and matched to the standards. If there is any discrepancy in the sectional weight, it may impact the balancing and stability of bottle. In the case of discrepancy, the design can be sent for reconsideration. This helps in preventing mass production of faulty design.
Sectional weight measurement plays a crucial role in R&D sector. A new design cannot be approved without testing it for different properties. If the sectional weight of the bottle fulfils the criteria, it can be sent for mass production.
- Different defects that can be pointed out
- Difference in mass distribution
- Faulty preforms
- Effect of ambience on blowing process
- Manual changes in blowing process
- Cavities glitches
- Inappropriate weight distribution