Cleaning the nozzle

Straight barrel nozzle
The straight barrel nozzle has a simple structure, and its internal structure only consists of two parts: a contraction section and a straight section. This type of nozzle cannot overcome the vortex phenomenon at the inlet end, resulting in large pressure loss and abrasive outlet velocity less than 100m/s under a pressure condition of 0.7MPa.
Venturi shaped nozzle
The Venturi shaped nozzle is structurally divided into three parts: a contraction section, a straight section, and a diffusion section, which significantly increases the difficulty of production.
The aerodynamic performance of the Venturi shaped nozzle is much better than that of the straight barrel shaped nozzle. The vortex phenomenon is significantly improved or no longer exists, and the pressure loss is significantly reduced. Under the same pressure conditions, the outlet speed of the abrasive can be increased by more than twice, close to the propagation speed of sound. The kinetic energy of the abrasive particles is greatly increased, and the ability to strike the surface of the workpiece is greatly enhanced, This is one of the main reasons for the improved efficiency of the Venturi nozzle.
A significant difference in the performance of a straight barrel nozzle and a Venturi nozzle lies in the uniformity of abrasive dispersion. The abrasive sprayed by the Venturi nozzle is evenly distributed in the dispersion area, while a large portion of the abrasive sprayed by the straight barrel nozzle is concentrated in the center of the dispersion area. The effective cleaning width of the nozzle on the workpiece surface is narrow, while the effective cleaning width of the Venturi nozzle on the workpiece surface is much larger, Moreover, the consistent abrasive force in the effective cleaning area, the full utilization of abrasive, and the improvement of work efficiency are inevitable results.
According to data, compared to a straight barrel nozzle, a Venturi nozzle can increase work efficiency by 15% to 40% and reduce abrasive consumption by 20%.
Double Venturi shaped nozzle
The double Venturi shaped nozzle has two nozzles in front and back, with gaps between them, and several small holes around the gaps. In this arrangement of nozzles with one large and one small, one front and one back, due to the action of high-speed airflow, a sufficiently large negative pressure is generated, which sucks in the surrounding air into the nozzle, causing the amount of air sprayed to be greater than the compressed air entering the nozzle, and increasing the outlet speed of the abrasive. In addition, the outlet diameter of the dual Venturi nozzle is slightly larger than that of a regular Venturi nozzle, and the divergent surface of the abrasive flow is 35% larger than that of a regular Venturi nozzle. Therefore, the cleaning efficiency is naturally higher than that of a regular Venturi nozzle.
The double Venturi nozzle has a smaller recoil force when used, which saves time and effort in operation. The theoretical high-speed working pressure is 0.42MPa, which is lower than other nozzles.
The inlet diameter of a regular Venturi nozzle is 1 inch. There is now a type of Venturi nozzle with an inlet diameter of 1.25 inches. Tests have shown that under a pressure of 0.69 MPa, the outlet velocity of a large inlet Venturi nozzle can reach 201 m/s, which is 12.5% higher than that of a regular Venturi nozzle.
Square hole nozzle
At present, a nozzle with square inlet and outlet ends has been developed abroad. Various tests have shown that this nozzle has higher work efficiency and better economy than a Venturi shaped nozzle.