The importance of accessories and consumables of sandblasting equipment
27.02.2017
To optimize the blasting process, a great importance should be given to accessories and consumables (nozzles, hoses, compressed air filtration devices, protection equipment for the operator, etc.).
Choosing the appropriate blasting nozzle must take into account:
the type of nozzle
the nozzle material
the type of abrasive used in the blasting process
the working pressure
and the compressor’s capacity.
In this respect, the straight nozzles were designed to achieve a reduced jet blast footprint when the operation is performed onsite or in a cabinet. These nozzles are designed for small applications, such as cleaning of parts, handrails, stairs, gratings, metal, welding seams or for reconditioning of statues.
On the other hand, the Venturi nozzles were designed to achieve an expanded footprint of the blasting jet and to increase the speed of the abrasive up to 100% for a given pressure. They are especially recommended when wishing to blast large areas.
Double Venturi Nozzles have two liners in both the converging & diverging end. The
machined holes allow the atmospheric air into the downstream section of the blast nozzles,
which along with the wider exit section, enable the size of blast pattern to increase whilst
minimizing the loss of abrasive velocity.
Another criterion to be taken into consideration when choosing the blasting nozzle is the material from which they are made of.
The lifetime of the nozzle depends on the material out of which the accesory is made of and the used abrazive type.
|
Nozzle material |
Steel media |
Slag media |
Aluminium oxide |
|
Tungsten Carbide |
400-800 |
300-400 |
300-400 |
|
Silicon Carbide |
500-900 |
350-600 |
350-600 |
|
Syclone |
600 - 1200 |
500-1000 |
500-1000 |
|
Boron Carbide |
1500-2500 |
750-1500 |
750-1500 |
The values are estimated for comparison reasons. Actual service life will vary depending on the blast pressure, media size, and the particle shape.
|
Ø Nozzle air |
Pressure ( bar) |
3,5 |
4,2 |
4,9 |
5,6 |
6,3 |
7 |
8,6 |
|
5mm |
Flow m3/min |
0,73 |
0,84 |
0,92 |
1,06 |
1,15 |
1,26 |
1,54 |
|
6mm |
Flow m3/min |
1,31 |
1,51 |
1,71 |
1,9 |
2,08 |
2,27 |
2,75 |
|
8mm |
Flow m3/min |
2,16 |
2,5 |
2,83 |
3,16 |
3,53 |
3,84 |
4,71 |
|
9,5mm |
Flow m3/min |
3,02 |
3,53 |
4 |
4,5 |
4,85 |
5,5 |
6,64 |
|
11mm |
Flow m3/min |
4,12 |
4,76 |
5,44 |
6,09 |
6,73 |
7,11 |
8,8 |
|
13mm |
Flow m3/min |
5,46 |
6,28 |
7,06 |
7,85 |
8,85 |
9,46 |
11,46 |
The blasting hose must withstand the abrasive action especially when it is used with high pressure compressed air. In addition, it must allow easy handling.
Modern blasting equipment are equipped with filters that retain impurities, pollutants, water and oil particles. Filtered air is used to drive both abrasive and for supplying the protection suit.
The protection costume) is a key component in order to ensure optimum working conditions for operator, with direct implications in the smooth running of the production process.
The air conditioning device for the blasting operator is able to modify the air temperature so that it meets the requirements of a proper work environment. Such a device can achieve an increase or decrease of the temperature up to 30°C.
