Polyester strapping_
Polyester (PET) strapping has become a popular alternative to steel for all but the very heaviest loads. Pound for pound, PET is stronger than steel, meaning that PET strapping with the same break load will be lighter than its steel strapping equivalent. It is also safer and easier to work with than steel and is resistant to moisture and corrosives.
PET is more elastic than steel, so it will provide better tension and package integrity as loads shift and settle. However, like polypropylene, it tends to deform and lose its ability to retain tension over time. Its performance is also degraded by exposure to extreme temperatures or UV light. For loads that will be exposed to the elements for extended periods of time, it may still be better to stick with steel.
PET strapping can be secured through heat sealing, friction welding or with metal strapping seals.
Serrated seals:
Serrated seals, also known as Gripper Seals, are made from CR Steel Strips. These seals have minute vertical projections inside the strapping seal to grip the strapping from both sides. The projections or serrations pierce into the strap and help in holding the strap ends in place inside the seals and prevent slippage.
Serrated seals are mostly used with polyester strapping since they have a very smooth surface thereby reducing the friction. Serrated seals are of two types - open type or C type and closed type.
Open type seals have equal flaps and close around the strap ends like any other common seals. They require common open type sealer.
Closed seals have unequal flaps and require a special sealer having uneven jaws which help in closing the seals around the strap properly and compress the flaps very tightly.
Seals are of 3 sizes - 1/2", 5/8" and 3/4". All seals are electro galvanized.
