The principle of high-pressure water jet cutting is to increase the water to an ultra-high pressure of 100-400 MPa, and through the orifice (φ0.15~φ0.4mm), the hydrothermal energy is converted into jet flow energy (flow rate up to 900mm/s). Cutting with this high speed dense water jet. Abrasive water jet cutting is the mixing of abrasive particles into the water jet, and the abrasive jet is formed by the mixing tube for cutting. In the abrasive jet, the water jet acts as a carrier to accelerate the abrasive particles. Due to the large abrasive mass and high hardness, the abrasive water jet has a larger jet flow than the water jet, and the cutting efficiency is stronger. The composition and process of the abrasive water jet cutting equipment are as follows:

Water supply system: soften the water, make the pH value 6~8, and finely filter to below 0.5μm. The working life of the sapphire water nozzle depends on the water quality. The life of the sapphire water nozzle is only 34h when it is directly used, the life of the softened water is 78h, and the life of the soft water is higher than 200h.

Booster system: The booster system is a key part of the equipment, the core of which is the supercharger. The boost ratio is generally 10:1 to 20:1. Water will be compressed by 12% at 420 MPa. In order to stabilize the water pressure within ±5%, an accumulator is required between the supercharger and the nozzle. Both the booster cylinder and the accumulator cylinder are ultra-high pressure vessels, so there is sufficient fatigue strength and working life.

High-pressure waterway system: The high-pressure waterway is connected to the booster system and the cutting head device. To use ultra-high pressure steel pipes and rotary joints, the steel pipes must be flexible, and all kinds of joints should be small, reliable and flexible. The rotary joints must have a variety of swirling patterns and a certain working life.

The abrasive supply system includes a silo, an abrasive, a flow valve, and a delivery tube. The shape of the silo and the mesh in the silo shall ensure that the abrasive supply is unobstructed and not blocked. The flow valve should be able to control the on and off of the abrasive flow and should also remove moisture from the transfer pipe.

Cutting head device: The cutting head comprises a high pressure water switching valve and a gemstone nozzle, a water/abrasive mixing chamber and a mixing tube. The mixing tube is a consumable part. It was previously made of hard gold, with a service life of about 2 hours for fine cutting and a rough cutting life of about 10 hours. Now the engineering ceramic materials are used up to 20~100h.

Receiving device: placed under the cutting head and the workpiece to collect the remaining jet of cutting. With energy dissipation, noise reduction, splash and safety features. Jet exposure can produce up to 42dB(A) of noise. After the receiving device is set, the noise is controlled to be within 80 to 90 dB (A).

Motion Control System: High-pressure water jet cutting is a high-precision cutting process that must be performed by high-precision cutting equipment. The current cutting equipment is controlled by a microcomputer or operated by an industrial robot, and can implement five-axis linkage. Repeatability can be up to ±0.05mm.

High-pressure abrasive water jet cutting is dust-free, odorless, non-toxic, non-sparking, low vibration and low noise. Especially suitable for harsh working environments and critical environments with explosion protection requirements. It can cut a variety of metal, non-metallic materials, a variety of hard, brittle, tough materials, such as titanium-nickel alloys, ceramics, glass, composites and so on. It is one of the most advanced cutting methods in the world.

Grating Fastening Tool

Grating Fastening Tool