Substituting copper with aluminium
Aluminium is much lighter and costs much less per weight unit than copper. Which means that you can get three meters of aluminium tube for the price of one meter of copper tube.
You’ve most likely been using copper for years in your heat exchangers, and even felt comfortable about that due to the low price of copper globally. So comfortable that someone may even have whispered to you that it is not worth taking the risk switching to aluminium tubes.
I’m here to say that it is time for you to wake up and take advantage of the benefits that aluminium tubes provide, including the economical benefits, before copper prices go up again. Let me explain why.
There are two very important considerations for the heating, ventilation, air conditioning and refrigeration industry – the HVAC&R industry. One is reducing costs through higher performance of your manufacturing processes. The other is related to increasing sustainability. Using aluminium solutions can help you achieve these goals.
Move over copper!
Many industries have already discovered the advantages of shifting from copper to aluminium, and for those in the HVAC&R industry, there are two ways to go:
- A quick and easy design change where you simply substitute round copper tubes with round aluminium tubes, to cash in the cost advantage and to improve corrosion resistance/avoid formicary corrosion.
- Step up and use aluminium micro-channel tubes to cut costs even further, to benefit from their compactness, and to reduce refrigerant charge to meet the European F-Gas Regulations by a comfortable margin.
Time to change
I’d like to go into detail about why it is time for you to give up copper for aluminium. Follow closely.
- Cost. Copper is a scarce resource, but there is an abundance of aluminium. Replacing copper with aluminium means that your material cost will be significantly lower and you will secure your economy against dramatic fluctuations in the metal markets.
- Recyclability. Aluminium is the most recyclable of all materials. It can be recycled over and over again without any loss of quality. That means it is sustainable and economical. In fact, the production of secondary aluminium, using recycled metal, saves more than 90 percent of the energy that would otherwise be used to produce primary aluminium.
- Durability. Aggressive environments accelerate the effects of corrosion – and copper is not immune to corrosion. Aluminium is self-protected by a stable oxide layer and, when following some simple design guidelines, its corrosion resistance is superior. By nature, it is immune to formicary corrosion and holds up in a variety of environments.
- Flexibility. Aluminium is easy to extrude, which means that all kinds of complex shapes can be produced. This cannot be done with other metals. For example, micro-channel tubes can only be extruded in aluminium, not in copper.
- Lighter weight. Aluminium tubes and heat exchangers weigh just half as much as the copper equivalent, providing a substantial reduction in system cost.
- Thermal performance. For fin-and-tube heat exchangers, there is no measurable difference in functional performance between aluminium and copper tubing. The limiting factor is the heat transfer coefficient between the air and fins.
The performance in aluminium micro-channel tube heat exchangers is significantly improved, due to design flexibility and to the brazed contact between tube and fin, which compared to a conventional fin-and-tube solution, will result in:
- Improved capacity per core volume ratio
- Lower refrigerant side pressure drop (optimum refrigerant pressure drop by passage optimization)
- Lower refrigerant charge
- Higher coefficient of performance (COP)