In a previous article, we saw how the raw materials of a tank often differ in quality despite being named the same general material, for example, different grades of steel and poly mixes. This is one identifiable factor in higher and lesser quality tanks. What determines the value and strength of poly tanks though? This article aims to answer that question by focusing on one very important metric – tank weight.
Tank Weight Determines Material Value
Consider the mineral resources like gold and iron, or natural produce like fruit and vegetables, beef, fish and the like. Weight is a metric used to determine how much there is of a commodity, and how much there is determines total value. Obviously then, you will pay a higher price for heavier amounts of minerals and produce since there is more of them.
What does this mean when comparing the weight of two similar sized tanks made of the same general material? If one poly tank weighs a lot more than another poly tank of the same capacity, then that means one manufacturer has paid for more “raw material” to be used in creating their tank. More polyethylene means greater material value. Consider if two different tanks were melted down and recycled, the one with more poly substance would be of higher value.
Steel is harder to compare by weight since there are different grades of steel. Some lighter steel with the same name might be more durable, so when comparing weights of two different steel tanks you need to make sure that the exact identical steel is used in both. While poly substances can differ in quality too, the different additives to poly mixes used in tank manufacturing will result in poly mixes weighing generally the same.
Tank Weight Reveals Greater Strength
There are several requirements that must be met if a poly tank manufacturer builds a tank to meet the Australian poly tank standard (AS/NZS 4766). Tanks manufactured to this standard, which aren’t at all mandatory, should be of a reasonable quality and strength to hold water and chemicals under normal atmospheric conditions.
There are many conditions that must be met, but two that you can check for when purchasing a poly tank is to ensure that it is constructed as one piece (there should be no side seams), and the walls at no point should be thinner than 4.5mm. National Poly Industries use an ultrasonic measuring device to confirm the thickness of our tanks to within 0.1mm accuracy. This device is used on 10 sections of the tank including areas of the lid, wall and base.
We also aim to exceed the Australian standard, whether that is a UV36 protection rating rather than a UV8 rating, performing additional non-required tests to ensure tank height and width dimensions are precise, or making use of more poly to provide thicker walls and base. The amount of poly material used in the tank, for example, to create thicker walls, the higher its structural strenth.
You can know which two different poly tanks have more poly material used in their construction by simply comparing their weight. This makes weight an important criterion when trying to discern which poly tank won’t warp, bulge or cave in like some report with inferior poly tanks. When comparing brands of similar tank sizes, always pay attention to the weight.
If you are looking for a water tank, National Poly Industries are leaders in poly tank manufacturing. Our tanks are certified to Australian Standards and made from a food-safe polyethylene mix with SUPA-UV protection. Each tank we make comes with a weight guarantee ensuring a high material value and stronger tank. Remaining ahead of the competition is important to us, so in addition to a quality tank we also strive to provide the best deal.