Strictly speaking, although the CNC waterjet cutter can cut more accurately than the flame and plasma cutting machine, it is not a precision machining tool, and it should not be able to mark the accuracy. When cutting sheet metal less than 10 mm, the cutting speed and compensation should be properly controlled, and the error can be + - 0.1 mm.
Because the target distance of the water jet is uncertain or changeable, the maximum cutting thickness of the CNC water jet cutter is not well defined. It is reasonable for the bold to say 400 mm and 500 mm, and the conservative to say within 100 mm. The current CNC water jet cutter generally has a flow rate of 2-3 liters and a working pressure of 200-380 MPa. The jet passes through the air resistance, and its energy decays rapidly. When it reaches 400 or 500 mm, it basically drifts away with the wind and has no striking force.
For general application, it is recommended that the thickness of cutting metal plate should not exceed 100 mm, and that of foam material such as sponge should not exceed 300 mm.
Working principle of the oil passage part:
The motor drives the oil pump to draw out the hydraulic oil from the oil tank and transmit it to the oil pressure pipeline through the one-way valve. At this time, the oil circuit is divided into three channels, one is connected with accumulator and pressure gauge, the pressure gauge shows oil pressure, the accumulator can stabilize oil pressure, the second circuit is connected with the directional valve, the other part is connected with overflow valve. When the hot water jet button is not pressed, the hydraulic oil from the oil pump directly flows back to the oil tank through the overflow valve, water-cooled cooler and oil return filter, and a small amount of hydraulic oil enters the oil chamber of the supercharger through the reversing valve, which is not enough to push the oil piston to change direction or change direction slowly; when the boiling water jet button is pressed, the relief valve is closed, and the hydraulic oil enters the oil chamber of the supercharger through the reversing valve. At the same time, the hydraulic oil on the other side of the oil piston is pushed out of the oil cylinder and flows back to the oil tank through the water-cooled cooler and oil return filter. When the oil piston is pushed to the end of the oil cylinder, it collides with the reversing ejector rod, which triggers the reversing valve to generate a reversing signal, so that the hydraulic oil circuit enters from the other end of the oil cylinder and the oil piston returns. At the end of the oil cylinder, the reversing rod is triggered, and the oil piston returns. In this way, the commutator is continuously triggered to reverse the oil circuit, thus forming the reciprocating motion of the supercharger.
Working principle of the waterway
After being filtered by the filter, the tap water is pressurized by the water pump and enters into the high-pressure cylinder at both ends of the supercharger. When the oil piston reciprocates, one end of the high-pressure cylinder enters the water through the water inlet check valve, and the water from the other end of the high-pressure cylinder is pushed out and enters the high-pressure pipeline through the water outlet check valve. This action is carried out alternately in the high-pressure cylinders at both ends to form continuous high-pressure water flow. Due to the existence of a supercharger commutation cycle, the pressure of output water flow forms periodic fluctuation. Therefore, the high-pressure water needs to be stabilized by the high-pressure accumulator and transported to the jet head through the high-pressure pipe. A gem nozzle with an aperture of 0.25-0.33mm is installed on the jet head. High-pressure water jet with great kinetic energy is formed under the restriction of gemstone nozzle, which can break through soft materials such as fiber, leather, and rubber. When a certain proportion of abrasive is mixed in the water arrow, the abrasive water jet is formed, which can penetrate any hard material.
When the hydraulic oil acts on the piston, the high-pressure plunger rod connected to the piston pushes out the water in the high-pressure cylinder. According to the law of conservation of energy, assuming that there is no friction loss, the work done by the two is equal. In this case, the oil pressure multiplied by the piston cross-sectional area is equal to the water pressure times the cross-sectional area of the plunger rod, that is, the ratio of water pressure to oil pressure is equal to the ratio of the cross-sectional area of the oil piston and the cross-sectional area of the high-pressure plunger rod. The ratio of the cross-sectional area of the oil piston and the cross-sectional area of the high-pressure plunger rod is called the "pressurization ratio". Since the ratio is fixed, the water pressure can be adjusted by controlling the oil pressure.