In this article, we will study the Definition, Parts, working principle, and Operation of Abrasive jet machining. We have also provided a PDF download link of the same at the very end. Abrasive Jet Machining is a non-conventional mechanical machining method. Jet velocity will be 150 to 300 m/sec and It is used for super alloys and Hard Materials. In this machining, the Abrasive particle size is 10-40 Micros
Abrasive Jet Machining Definition
Abrasive jet machining is the process of impinging the high-speed stream of abrasive particles by high-pressure gas or air on the work surface through a nozzle and metal removal occurs due to erosion caused by high-speed abrasive particles. Because of repeated impacts small bits of material get loosened which is carried away by jet and exposes the fresh surface to the jet.
Abrasive Jet Machining Parts or Construction
Abrasive Jet machining Consists of the following parts
- Gas Supply
- Filter
- Pressure Gauge
- Regulator
- Mixing chamber
- Nozzle
Gas Supply
- Gas is supplied to the system for the operation. Here we also use compressed air instead of other gas.
Filter
- Filter indicates the cleanness of the fuel supply.
- Here the work is to clean the fuel if there are any dust particles present.
Pressure Gauge
- This device will check whether the required amount of pressure is there or not.
- Normally this device works to check the pressure.
Regulator
- The regulator as the name indicates it controls the flow.
- It controls the compressed air flowing through the pipe.
Mixing Chamber
- Here we supply the abrasive particles and there already the amount of compressed air comes from the pipe.
- Both will get a mix that’s why this is called a Mixing chamber.
Nozzle
- This is made up of hard material. The diameter of the nozzle is about 0.18 to 0.8 mm.
Working Principle of Abrasive Jet Machining
The figure shown is the above Abrasive jet Machining. It consists of a mixing chamber, gas filter, pressure gauge, regulator, and nozzle. The filtered gas at a pressure of 2 to 8 kgf/cm2 is supplied to the mixing chamber containing the abrasive powder and vibrating at 50 Hz, where it mixes with abrasive particles and then enters into the connecting hose.
The abrasive and gas mixture comes out from the nozzle at a high velocity ranging from 150 to 300 meters/minute and impinges over the work surface causing abrasion action by repeated impacts and the material is removed by erosion. The abrasive power feed rate can be controlled by the amplitude of vibration of the mixing chamber. A pressure regulator controls the gas flow and pressure.
To control the size and shape of the cut, either the workpiece or nozzle is moved by cams, pantographs, or any other suitable mechanism. The carrier gas should be cheap and non-toxic and easily available, It is generally air or nitrogen. Abrasive generally used are Aluminum oxide, Silicon carbide, or glass powder.
The nozzle is generally made of harder material such as ceramic or tungsten carbide to reduce abrasion wear. The material removal rate depends on the diameter of the nozzle, jet pressure, composition of mixtures, Hardness of abrasive particles and workpiece, Particle size, the velocity of the jet, and distance between work and nozzle.
Applications of Abrasive Jet Machining
- Cutting slots and thin sections.
- Contouring and drilling operation.
- Producing shallow crevices and deburring.
- Producing intricate hole shapes in a hard and brittle material.
- Cleaning and polishing the plastic, nylon, and Teflon component.
- Frosting of the interior surface of glass tubes.
- Etching of marking of glass cylinders.
- Machining super-alloys and refractory material.
Abrasive Jet Machining Advantages
- The surface finish can be obtained smooth.
- The cost of equipment is low.
- Ability to cut fragile and heat-sensitive material without damage.
- Ability to cut intricate hole shapes in hard and brittle material.
- The main advantages are its flexibility, and low heat production.
Abrasive Jet Machining Disadvantages
- The material removal rate is low.
- Poor machining accuracy.
- High nozzle wear rate.
- The soft material cannot be machined.
- Additional cleaning of the work surface is required due to the sticking of abrasive grains in softer material.
FAQ
What Is The Abrasive Jet Machining Process?
It is a non-conventional mechanical machining method. The process of impinging the high-speed stream of abrasive particles by high-pressure gas or air on the work surface through a nozzle and metal removal occurs due to erosion caused by high-speed abrasive particles.
What are the advantages of AJM?
- The surface finish can be obtained smoothly.
- The cost of equipment is low.
- Ability to cut fragile and heat-sensitive material without damage.
- Ability to cut intricate hole shapes in hard and brittle material.
- The main advantages are its flexibility and low heat production.
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