Belt drive versus direct drive: A comparison of differences and benefits
Estimated reading time: 5 minutes
When you are in the market for an air compressor, you may be faced with the choice between a belt drive or direct drive compressor. This article will help you understand their differences and their respective advantages.
Belt drive versus direct drive – The technology
One of the first things to remember is that belt drive and direct drive versions are available for both rotary screw air compressors and piston compressors.
Each option works effectively and can be beneficial to your needs, but they are very different. A belt drive compressor consists of a belt that is connected to the motor of the compressor pump. When the motor runs, the belt turns, powering the pump to your air compressor. When using a direct drive air compressor, the crankshaft is connected directly to the compressor's motor.
Belt drive versus direct drive – The benefits that matter to you
Which is better? Well, it depends on what is important to you. If your primary concerns are reliability, ease of operation, cost-effectiveness and power, then a direct drive compressor is likely right for you.
If you need to adjust speed and power, a belt drive may be the better option. As long as it is properly lubricated, a belt drive compressor will run more smoothly and therefore quieter. That makes it a good choice for environments in which noise levels matter.
Start from your needs
That means your needs will play a big role in the decision of “belt drive versus direct drive”. In that sense, it’s really not so much about “belt drive versus direct drive” but rather “infrequent use versus constant operation” or “flexibility versus energy efficiency”.
For example, if you have a workshop and you use your pneumatic tools not as frequently, then a smaller compressor with belt drive will suffice – such as the Atlas Copco G 15-22, which is reliable, user friendly and has a low initial investment cost.
If, however, you use compressed air all the time and are particularly mindful of keeping energy costs down, or if you have to operate your compressor in harsh conditions, then you are probably better served with a direct drive model – such as Atlas Copco’s LT or LE, which deliver unmatched efficiency and performance every time you turn it on.
Their different strengths are the result of the very different drive technology described above.
Environment and use
The key to taking the greatest possible advantage of the benefits of each type of compressor is to know where, how – and how much – it will be used.
Energy-related expenses constitute the majority of the total cost of ownership of industrial compressors. That means that one that is used a lot should be as energy efficient as possible to keep those costs down. In that case, a direct drive model probably is the right choice.
However, if the compressor is used intermittently, then the belt-driven version is likely best as it is more flexible regarding air flow and pressure adjustments.
The latter is also easier to install and maintain, which makes them the right choice for people who are not experts.
Finally, as noted above, the environment in which the compressor has to operate matters. Belt-driven models, which are quieter, are generally better for environments in which noise emissions have to be kept low, e.g. in indoor environments or residential neighborhoods.
Direct drive compressors are often the right choice for harsh environments because they are designed to withstand those conditions.
Belt drive versus direct drive – The final verdict
As you can see, as long as you go into your compressor selection with a good idea of what it will be used for, the decision regarding belt drive versus direct drive practically makes itself.
Ask an air system professional about the best option for your needs.