What size compressor do I need? [Updated for 2020]
What size compressor do I need for tyre machine? It’s a common question and when you look at the number of compressors available it’s no surprise.
When it comes to sizing an air compressor for your garage, there are a few things to watch out for. Following the steps below & you should be on the right track to ordering the right size air compressor for your tyre machine.
What size air compressor for changing tyres – top tips!
First things first, a bigger vessel does not mean more air.
The most important thing is the combination between the pump output (CFM) and the vessel size (v). There is also the maximum pressure of the compressor (psi or Bar). All of these need to match the planned usage for your air compressor. Is it just a compressor for tyre machine use or full garage tools?
So what size compressor do you need?
In a normal automotive application, you will require air at regular intervals during the day, but rarely constantly.
All air compressors sold on Tyre Bay Direct are fitted with a pressure switch. On most models, this will turn the compressor on at 7 Bar and off again at 10 Bar.
Ideally, you want your compressor operating around 80% of the time. Any more than this and the motor unit could be damaged. Any less and you risk water condensation in the oil, which is not good for the unit.
Understanding Pressure Rating
The decision on the pressure output is a simple one. Base it on the highest pressure you will be inflating tyres to or operating tools at. Go for a pressure slightly above that & you’re covered
What size air compressor for changing tyres?
10 bar (or 150psi) is normally adequate for most automotive applications.
What size air compressor do I need to fill truck tyres?
Commercial Tyres including what size air compressor you need to inflate tractor tyres can vary. These can operate at 120 or even 130psi & so a 13 bar compressor is required.
Understanding Output (CFM)
The output required is a simple calculation. Every piece of equipment you power by compressed air has a CFM rating.
This describes how many CFM of air the tool requires to operate effectively. Let’s say for instance you have the following, potentially all happening at once;
- Tyre Changer using 4 CFM
- Air Too using 4 CFM
- Tyre Inflation using 2 CFM
That’s a total of 10 CFM so a compressor of around 12 CFM FAD will be more than adequate.
REMEMBER: if you are a single operator and none of the above will be happening simultaneously, you can use a 6-8 CFM compressor instead!
Understanding Vessel Size
The size of the vessel does not directly correlate to the supply of compressed air. This is why we say “what size compressor for tyre machine does not literally mean the size of the tank. You’ve got to consider the above.”
The only time vessel size over 200 litres is really necessary is if you require a large amount of air for a short period. This is rarely the case in automotive environments.
A small 6 CFM pump unit could fill a 500-litre vessel to 10 bar in about ½ hour. This means if you use 4000 litres of air in 2 minutes, but only once an hour, you don’t need a big pump unit, just a big vessel.
The importance of pump unit vs. vessel size is perfectly shown in the price.
The pump unit will increase the price of a compressor more than the vessel. That is why getting the combination right is critical when selecting your air compressor.
One final thing to consider when sizing your air compressor
The main another factor to consider in selecting a compressor is the workshop layout!
This ultimately can be more important than performance & determine the type of compressor you buy. The layout can determine:
- Noise levels
All of this needs to be considered in relation to where the compressor will sit & all is available on the product pages for our compressors.
What about mobile tyre-fitting compressors?
Consideration for mobile tyre-fitting will be exactly the same as above. The compressor will still need to follow these considerations & most will fit comfortably in your mobile tyre-fitting van. Our team will be happy & can even organise your full mobile tyre-fitting van installation. Call them today on 01527 883 580.
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Ask us what size compressor you need for tyre machine!
Our team are experts in all things garage equipment & happy to help.
Give them a call today on 01527 883 580. They’ll be able to determine the perfect size compressor for you based on how you operate, where your compressor will sit & a range of other factors as seen above.