Know how to use and maintain an air compressor
An alternative source of energy, compress air makes it possible to operate pneumatic tools to clean, lubricate, chisel, paint, sand, polish, screw … This energy is obtain thanks to a air compressor with an electric or thermal motor which actuates one or two pistons responsible for sucking and compressing the air before sending it to a storage tank.
Description of an air compressor
 |
01 | Storage tank |
| 02 | Working pressure gauge | |
| 03 | Tank pressure gauge | |
| 04 | Purifier filter | |
| 05 | Compress air outlet | |
| 06 | Working pressure adjustment | |
| 07 | Pressure switch | |
| 08 | Electric motor | |
| 09 | Drive belt | |
| 10 | Compression pump |
Pneumatic tools use
 Spray gun |
 Seal gun |
 Blow gun |
 Inflator |
 Impact wrench |
 Chipper |
 Sander |
 Stapler, nailer |
How to choose your compressor?
- The first criterion of choice, when one wishes to buy a compressor, is the return air flow. The higher it is (in liters / min or m3 / h), the greater the possibilities.
- The engine power and the number of pistons determine the suction speed.
- The capacity of the tank influences the continuous work.
On average, the powers go from 2 to 4 HP and the most use tanks contain from 50 to 100 liters.
- With 50 liters you can clean, inflate, staple, nail and do small painting jobs.
- With 100 liters, you also have the possibility of sanding, chiselling and painting large areas.
On some devices, the applications are clearly indicate, as at Mécafer.
There remains the price which can, depending on performance, vary from 150 to more than 1000 €.
Getting started with the electric compressor
The most common models use an asynchronous electric motor.
The power is express in CV or kW.
The belt system allows for an independent motor and good ventilation of the compression head.
Getting start with the portable compressor
Equip with a handle and four wheels, this 100-liter compressor with the full tank weighs almost 85 kg.
It is not very easy to move around the garden, but it is possible to equip yourself with a wall hose reel or an extension.
Vertical tank compressors are more convenient to move and store.
Filling the tank
The pistons suck in the ambient air then send it through a rigid or flexible duct, into a buffer tank where it increases in pressure to 8 or 10 bars. The tanks have a storage capacity of 10 to 200 liters.
On this model, the tank is 100 liters with a restore air flow rate of 320 l / min.
Pressure controllers
The compressor is equip with two pressure gauges.
The first indicates the air pressure in the tank.
The second is use to adjust the operating pressure, which differs from one tool to another.
The pressure level is adjust using the dial above.
Air purifier filter
The ambient humidity suck in by the compressor or the condensation present on the wall of the tank produce humidity at the tank outlet.
This can disrupt painting work and oxidize the mechanism of pneumatic tools.
This model is fitt as standard with an air purifying filter which empties.
Otherwise, it is an accessory that can be plug into the hose outlet.
Compressor start-up and maintenance
Connection
Compress air is return via a flexible hose which is connect with quick couplings on the compressor and the pneumatic tool.
The end of the hose must be fully engage in the compressor fitting to release the ball which blocks the air passage.
Hoses are not provide, but are easily found in GSB or on the Internet.
Hoses
They exist in different diameters and qualities to best withstand pressure and heating.
- Nylon 6 to 8 mm internal diameter for 8 to 10 bars maximum pressure.
- In reinforce nylon 8 to 12 mm in diameter for 10 to 15 bars maximum.
- For a blow gun or inflator, a diameter of 6 to 8 mm is sufficient.
- For an impact wrench, chisel, stapler or paint gun, it is better to choose a diameter of 10 to 12 mm.
The start-up
After connecting the device to the mains, all you have to do is turn the knob locate on the pressure switch unit.
Then, it is the pressure switch which manages. It switches off the motor as soon as the maximum pressure in the tank is reach (here 10 bars) and switches it on again when the pressure drops between 4 and 7 bars.
Once the tank is full, the compressor can also be use unplug.
Cleaning the air filter
The air is suck in each time the piston descends and then return to the storage tank on each rise.
Valves prevent the air from coming out.
On suction, the air passes through a filter which removes impurities.
Easy to access, it should be check and clean regularly.
You can connect a blower to the compressor for cleaning.
Oil level
Oil is vital for the life of the crankshaft and pistons.
Before and after each use, it is advisable to check its level.
The dipstick is locate at the bottom of the compressor unit housing.
Note that some models (Mécafer) operate without oil.
Emptying the tank
The steel tank is sensitive to oxidation due to condensation and can deteriorate quickly.
Under the tank, a drain plug allows the water still present after use to be evacuate.
Common pneumatic tools
Pneumatic tools like chisel, impact wrench, sanders… are as efficient as their power-hand counterparts.
The air flow rate and the working pressure are indicate on the tool or the packaging.
The mechanism of pneumatic tools should be lubricate regularly.
On this impact wrench, oil enters through the air inlet port.
It is possible to equip an oiler couple to a wall air purifier.
The tools are deliver with the air connection remove.
Before screwing it in and to avoid any air leakage, line its thread with two turns of Teflon.
The latter is put in place in the reverse direction of screwing, from right to left.
Blow gun and inflator
Two tools are essential with a compressor: the blow gun and the inflator with pressure gauge.
The former is ideal for dusting tools and mechanical parts and the latter for controlling the pressure of car and bicycle tires.
A fitting set is use to inflate air mattresses, small swimming pools, balloons, etc.
Orbital sander
The orbital sander is commonly use by bodybuilders.
Some sanding phases are carried out by wetting the abrasive.
With compress air, any risk of electrocution is exclude.
The orbital sander is also very practical in the pneumatic version.
Air consumption
If the tool use consumes more air than the compressor output capacity, the latter empties more quickly and lowers the pressure. It is then necessary to wait for the filling of the tank to resume work.
The table below provides information on the consumption and the operating pressure of the most commonly use tools.
