The pressure change of the high-pressure cleaning machine can affect other parameters of the system, and appropriate adjustment of the corresponding pressure parameters can reduce the pressure loss during the process of obtaining the optimal impact force. According to the formula N=16.7PQ/1000, it can be known that the energy loss of the high-pressure cleaning machine is directly proportional to the pressure. Therefore, the pressure loss of high-pressure cleaning machines can be mainly studied from three aspects, namely the pressure loss in the upper part of the high-pressure cleaning machine, the pressure loss and pressure in the high-pressure hose section, and the loss of the nozzle.
Pressure loss in the upper part of the high-pressure cleaning machine:
On a high-pressure cleaning machine, there is a section of high-pressure water pipe from the outlet of the high-pressure pump to the outlet of the drum, so this is called the pressure loss in the upper part of the high-pressure cleaning machine. This section of high-pressure hose has 4 to 5 joints and elbows, and the high-pressure water rapidly rotates, resulting in losses typically reaching 5% of the total loss of the cleaning system, approximately 15-20 bar. Although the pressure loss is not significant, the pressure loss in the upper part of the high-pressure cleaning machine should be considered when calculating the pressure loss of the high-pressure cleaning machine.
Pressure loss of high-pressure cleaning machine nozzle:
The direct cleaning tool for high-pressure cleaning machines is the spray gun. The nozzle is the first to bear the brunt, as it produces high-pressure water jets. It is the only tool that converts the pressure energy of a high-pressure pump into velocity energy. The pressure loss of the nozzle is mainly caused by the local pressure concentration of high-pressure water in the nozzle and sudden changes in dynamic pressure. Pressure loss of high-pressure water at the nozzle inlet; Pressure loss caused by significant changes in nozzle flow channel cross-section; Pressure loss caused by sudden changes in the direction of water flow in the nozzle; Pressure loss caused by the branching of a single stream of water into multiple streams of water; The outlet pressure loss caused by the high-pressure water jet formed by the outflow nozzle of high-pressure water.
The pressure loss caused by high-pressure water flowing in the nozzle is very large. If the shape and inner hole structure of the nozzle are not designed properly, the maximum pressure loss may account for 60% of the total pressure loss of the high-pressure cleaner. The pressure loss of the nozzle section accounts for the largest proportion of the total pressure loss of the high-pressure cleaning machine. In order to reduce the pressure loss of the nozzle, this goal can only be achieved through correct design and precise production of the internal structure of the nozzle.
Pressure loss in the high-pressure hose section of the high-pressure cleaning machine:
The high-pressure hose section is a long hose that runs from the outlet of the reel to the inlet of the spray gun. The pressure loss of this part of the pipeline accounts for more than 50% of the total pressure loss of the high-pressure cleaning machine, and can even reach 2/3. The pressure loss of this part of the pipeline can be obtained through two methods, one is through calculation, and the other is through experimentation. When calculating, the flowing high-pressure water should be considered as turbulent, as turbulence is consistent with the actual situation.
When calculating the pressure loss of the high-pressure hose section, the winding loss of the high-pressure hose on the reel should also be considered. The smaller the curvature radius of the winding, the more turns it has, and the greater the pressure loss. In practical applications, if the selection or handling of high-pressure hoses is improper, the cleaning effect of high-pressure cleaning machines will be greatly reduced, and even the original intention at the time of purchase cannot be achieved.