Our offices are closed from the 21st December until 6th January.

Aluminum versus cast iron – Which piston compressor material is best?

Thanks in large part due to their versatility and low cost, piston compressors are among the most common air compressors being used today. They are the right choice for a wide range of applications, from DIY to workshops to dentists.

Once you have concluded that a piston compressor also meets your needs best, there is one more decision to make: aluminum versus cast iron.

If you have used our guide on what type of air compressor to choose, then you will know that the first step in selecting the right material for your compressor (which in this case means the pump, cylinders, flywheel and valves) is to figure out how you want to use your new compressor.

When you know, the choice may be easier than you think – even for a layperson. 

Aluminum versus cast iron – lightweight versus heavy duty

To anybody familiar with metals, the main difference between the two is obvious: Aluminum is much lighter. Despite its low weight, aluminium is very strong. It features superior malleability and excellent corrosion resistance, is easy to machine, not susceptible to rust formation, and has good electrical and thermal conductivity. The latter is particularly important for piston compressors because it results in good heat dissipation. In addition, aluminium will heat up enough to vaporize any condensate in the oil. Aluminium’s low density makes it the logical material to use for lightweight compressors that are easier to transport, install, and move around.

Cast iron, on the other hand, is able to withstand high loads. It is a perfect shock absorber. While cast iron is sometimes viewed as problematic because it gives off dust that may be harmful to humans, this is not a problem with Atlas Copco compressors. Among the advantages of cast iron compressors is also that they have long service intervals and feature a high cooling performance. Because it is very durable and much heavier than aluminium, cast iron is the perfect material for compressors that need to operate in heavy duty environments and extreme conditions. One drawback is that cast iron is not very flexible.

Aluminum versus cast iron – your needs decide

Because both materials have distinct advantages, it’s impossible to say which one is better. Ultimately, you have to decide which one is better for you.

However, here is a rule of thumb: If you need a small, flexible compressor, especially for non-stationary use, then aluminium is often the material of choice.

But if durability is most important to you and/or your compressor has to function reliably in tough conditions, then you will probably prefer a cast iron model.

One final note, which is less important for Atlas Copco compressors because of their outstanding durability but should be mentioned in a world in which sustainability is increasingly important: Of the two materials, aluminium is much easier to recycle.

Ask an us about the best options for your needs.

Do you have an idea for our #expertcorner? Let us know!

Useful links:

Book Your Compressor Service

Who we are and how Ash Air can help your business!

Ash Air has been around in New Zealand since 1979, and we’ve grown into a nationwide company with international support and a reputation for quality and reliability.We look after all things compressed air for your business!

  • Reciprocating, Screw, air compressors
  • Vacuum pumps
  • Nitrogen
  • An extensive line of air treatment components

Ash Air's range of Chicago Pneumatic, Alup, Pneumatech, and Quincy compressors are used extensively around the world in industries ranging from oil and gas to food, automotive and farming, and we bring you these world class compressors here in the land of the long white cloud.Our technicians are compressed air equipment experts and are dedicated to addressing customer needs. Supported by a 13 locations nationwide, Ash Air offers one of the widest selections of compressed air equipment and parts available today in New Zealand.

Reliability and Efficiency

With Ash Air compressors, you can count on reliability and high performance for even the most demanding applications. We focus our efforts on the following:

  • Increasing uptime
  • Reducing unexpected repairs
  • Reducing energy consumption
  • Improving the cleanliness of compressed air


Talk to the team today:  CONTACT US CONTACT US

Read more from our #expertcorner


Just like any other equipment, a compressed air installation also requires the necessary maintenance work during its entire lifespan. Even though maintenance costs are only about 5 to 10% of a machine's annual operating costs, failure to budget for maintenance can have potentially disastrous consequences. …


The air dyer is one of the most ignored cooler in the system. A dirty condenser will cause water in the lines, or worse it will cause complete dryer failure. …


Using nitrogen is not about fully replacing CO2, but it can reduce their consumption of CO2 by close to 70%. Using nitrogen is about sustainability. Creating your own nitrogen is easy and will reduce the use of a greenhouse gas, which is better for the environment. It will also save you money as early as month one adding that savings to your bottom line. …


A question that is occasionally asked by our customers to Ash Air is 'what is the cost of compressed air?'  This article looks at the product costs involved with compressed air, as well as minimising the energy cost of compressors and cost allocation. When looking at these factors, we need to realise what causes dropped efficiency of your compressor, leading to increased costs of compressed air. …


You may have great fall protection measures in place to keep employees safe when working at height, but what about their co-workers below? Dropped tools and other falling objects are a major hazard – and one that isn’t always fully addressed.  …


Providing a safe working environment for operators is essential, especially when using pneumatic tools and compressed air. If there is a failure in the air network and the hose is not adequately clamped, the resulting whiplash could be devastating. Failure to follow best practice can result in injuries, associated production downtime and decreased productivity. …


A common questions asked is why do I need an air dryer for my compressor? Typically, air compressors produce water, and although the water can be drained, there can still be aerosol and vapour droplets that are present. This is because water cannoet be compressed. Water can damage your compressor by corroding the valves, pipes and machinery controls, which will cost you time and money to resolve. In the long run, the cost of a new compressor is a small price to pay compared to the loss of production that could potentially arise due to water damage in your compressor.





…


Air compressors can fail for an assortment of different reasons: Normal wear and tear, lifespan and age of the unit, poor maintenance, power surge, install issues are just a few the come to mind. Check out this blog to find out our top 7 tips to ensure your compressor is looked after!  …


That cold, rainy, and in some places icey New Zealand winter is upon us, and with the following air compressor tips, your air system will be prepared with the preferred temperatures, despite the weather outside. Regardless of whether or not it actually snows or freezes up where you live, most winterisation service recommendations are also basic, solid maintenance procedures that will help extend the life and operational efficiencies of air compressors regardless of whether you live in Queenstown or Northland. …


If you're wondering what an air compressor actually is, you've come to the right place. Simply, air compressors convert power in to air that is pressurised which is then used to power air tools such as spray guns. Air compressors are used in a wide range of applications, so naturally if you want one that will be designed for spray painting your vehicle, you want a compressor specifically made for spray guns! This way your compressor will be able to provide the right amount of power to perform the job. …


Compressed air plays a fundamental role in industrial activities. Depending on the type of application, the energy cost of producing compressed air can be very high. Below are some tips to save on you compressor bill. …


Air Compressors are essential tools in a variety of industrial settings. No matter what industry you are in having a reliable air compressor can be a crucial part of getting the job done efficiently. However, like an investment, air compressors require upkeep and maintenance, and eventually will need to be upgraded. But how do you know when it’s time to upgrade your air compressor? Here are some things you need to consider. …


When it comes to laser cutting and other industrial processes, the choice of assist gas is crucial in achieving optimal results. Nitrogen and oxygen are commonly utilized as assist gases, each with its own unique properties and applications. Understanding the characteristics of both gases, will help you to make an informed decision to ensure precision, efficiency, and cost-effectiveness in your operations. …


Mobile air compressors are portable, towable compressors particularly useful for applications that suit the construction and roading industry! You'll often see a mobile compressor being used for sandblasting, irrigation blow-outs, and for quarrying tools such as pneumatic block cutters and rock drills.   …


Did you know that Chicago Pneumatic helped man land on the moon? Notice in this photo of the Apollo 11 landing what appear to be "soccer balls" on top of the capsule. They were inflated through a compressor specially developed by Chicago Pneumatic for NASA. …


Your company purchased an air dryer for your compressor, now where should you install it? One of the most common things we see in the industry are air dryers being stored on top of the compressors. Seems like a wasted space not being used on top of the compressor, right? Wrong. …


When using air compressors, there are many variables that are integral to the quality and effectiveness of your compressed air. When dryer air is necessary, being able to constantly and accurately monitor dew points can be a critical factor to your operation. …


Compressed air plays an integral role in breweries both large and small around the world. From start to finish, all details in the brewing process are managed in fine detail and having the right air compressor is no exception. …


We Kiwi's love our Coffee! Coffee, like all other food & beverage products, must go through a preservation process to keep the beans fresh during storage and packaging before they reach the consumer. Coffee that is not properly stored after it is roasted will lose a large amount of carbon dioxide, which lessens its' flavor and speeds up the staling process. One of the most common ways to preserve the freshness of coffee is the use of nitrogen gas. Learn more here: …


Air compressors are helpful for an enormous range of applications such as air filling, packaging, tools, HVAC control, and more! One possible drawback is the amount of electricity they use; air compressors can be a huge drain on energy if used ​inefficiency...  …


We get it, buying an air compressor is a big financial decision. And now we are suggesting that you need two air compressors, not just one. Ask yourself one question- Can your business still run if your air compressor goes down? …

Show More