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Table: Max. compressor size required as a function of the blasting nozzle
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Diameter
blast nozzle
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Compressor
output
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Blasting hose
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Air hose
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mm
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m3/min
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mm
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Zoll
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6
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1,8
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13/7; 19/7
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1/2; 3/4
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8
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3,2
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19/7; 25/7
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3/4; 1
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10
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5,0
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25/7; 32/8
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1; 1 1/4
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12
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7,2
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32/8
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1 1/4
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14
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9,8
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32/8; 49/8
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1 1/4; 1 1/2
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16
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12,8
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32/8; 49/8
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1 1/4; 1 1/2
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The shorter the hose and the bigger the diameter of the hose, the lower is the loss of blasting power. (This concerns the air hose between the compressor and the machine and the blasting hose).
A. The nozzle: Standard nozzles are Cylinder- and Venturi-nozzles, but the Venturi-nozzle produces a higher speed of the blasting mixture at the nozzle. The result of the higher blasting mixture speed is a higher production efficiency of blasting power (upto 30%).Also long blasting nozzles have upto 20% more blasting power in comparison to short nozzles.
B. Handling of the blasting nozzle: This is not a question of the machine or the equipment, but of the training of the operator. A well trained operator with experience get up to 50% more production efficiency than a operator without training.The first step to get the maximum blasting performance is to have a good planning, the right blasting mixture and the right setting of the machine.After planning, the operator has to know which result is required, so that the operator knows how to handel the nozzle.
Movement of the nozzle: The best way to move the blasting nozzle on large objects is to circulating and side longe the nozzle at the same time.If you don´t circular the nozzle, the surface will look unintegrated Pic. 1).
The faster the circulating and the side longe, the lower the wear on the surface.
Distance of the nozzle: The normal distance between object to be blasted and blasting nozzle is approx. 20 to 25 cm. One possibility to influence the aggressiveness of the blasting process, is to increase the distance between object and blasting nozzle (Pic. 2).
The nearer the blasting nozzle to the object, the stronger the aggressiveness of the nozzle and the smaller the surface simultaneously treated.
Angle of the nozzle: The normal angle between object and blasting nozzle is 20 to 45°.One possibility to influence the aggressiveness of the blasting process, is to increase the angle between object and blasting nozzle (Pic. 3).
The smaller the specified angle to the object, the stronger the aggressiveness of the nozzle and the smaller the surface simultaneously treated.
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