Why Plastic Parts Are Rapidly Overtaking Metal

Plastic vs metal – it’s a long-debated topic in agricultural, mechanical, automotive and several other industries. While metal parts and assets have been king since the first machines were created, new science has made a new (better suited) successor. Enter plastic. 

Traditionally plastics struggled to compete with the strength and durability of metals. However, current plastic technologies have allowed this substance to perform as well as, and, in some cases better than, metal. 

So when both substances can perform the same job at the same level, it boils down to cost, weight and efficiency – to which plastic is the clear victor. 

If you haven’t already, it’s time to start rethinking where you’re using metal parts and consider if you could benefit from a cheaper and better tool. 

Plastic – Stronger Than You’d Think

Plastics excel at having a high strength-to-weight ratio. It can withstand more stress before failure while weighing less than a metal part. Combine this with better tensile strength and a higher ability to resist being deformed under mass density and plastic makes a good argument against metal enthusiasts. 

The below diagram shows a broad performance range of several plastics (categorised in Polymer and Composite categories) and how they compare to metal options. While the strongest metals rank higher than plastics, the plastic options aren’t far behind and have a lower density. 

Better Chemical Resistances 

Plastics are generally less susceptible to damage from chemicals or chemical reactions. Metal water storage tanks can cause zinc to leak through your water supply, leaving an unpleasant metallic taste. 

Worse, a study by the Public and Environmental Health Service in Tasmania found harmful lead levels in some stainless steel tanks. Steel tanks are used commonly in the mining industry to store sulfuric acid. At a high concentration (98% or above) steel can handle the acidic qualities of the acid for years. However, once the solution is diluted (Lower than 93%) the formula becomes highly corrosive. Poly liquid storage tanks, which we specialise in, can dependably store this acid at most concentrations. 

Poly Plastics, The Lightweight Champion 

More weight means more power is needed to move it. One of the best reasons to replace your heavy steel products with lightweight plastic products is you significantly lower your load. 

Our poly agricultural equipment is easy to roll, lift and reposition. Very rarely do we rely on heavy machinery when it comes to installing even our largest products. If you’re looking to replace a vehicle-mounted item with a plastic one, you’ll have improved fuel efficiency and no problem lifting them on or off your ute.

Faster Fabrication Times To Meet Strict Deadlines

Time equals money! When you’re in a pinch and need a replacement part fast, utilising plastic manufacturing will have you back on your feet long before a metal replacement can be created. 

Plastic’s design flexibility allows for designs to be created in one part, whereas metal parts often require assembly or welding to create one piece. Because of a more simplistic design process, you save time, labour and cost compared to what metal manufacturing would take. 

Heat Resistance

The biggest argument against plastics is it’s lower melting point than popular metals like steel or iron. However new high-performance thermoplastics technology has a melting point of 3593.333°C where carbon steel melts between 1425 – 1540°C. Still, most common plastics will melt somewhere in the 200°C range.

Know When It’s Right To Use 

Your safety and wellbeing is our priority at Global. While we love the benefits plastics offer, sometimes metal is the right material for the job. Consider these cons when planning your replacements.

Limited Wear Resistance

Plastic’s low resistance threshold means it may be affected by high temperatures, acidity and other corrosive elements. However, there are higher-resistance plastic options better suited for handling chemicals. For example, our rotomoulded cartage tanks are suitable for transporting diesel and a range of other substances. 

Lower Structural Strength

Plastics are unsuited for supporting structures and replacing high-weight bearing parts of heavy machinery.  

If you feel that lightweight plastic will benefit you, the team at Global Rotomoulding can help out. We create a range of tanks, parts and other agricultural equipment. If you want a custom plastic piece to help you out, call us today to see how we can help. 

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