Abrasive jet machining / Definition, parts, working, advantages, disadvantages of abrasive jet machining

Introduction:

Abrasive jet machining is a mechanical energy based unconventional machining process mostly used in the machining of hard metals.  

In this machining, a concentrated stream of abrasive particles like aluminum oxide, silicon carbide, diamond powder, glass particles, etc is forced to strike a piece of the workpiece at high velocity.

These high velocity abrasive particles cut the metal into small pieces.

See in figure abrasive jet machining process and their working procedure described below in detail.

Working Procedure of Abrasive Jet Machining:

1. Firstly in abrasive jet machining air or gas like nitrogen, carbon dioxide, etc compressed in a gas compressor. Where the density and pressure of the gas increases. 
2. Now it sends the compressed gas to the filtration unit, from where the dust and other suspended particles are removed. 
3. Then It sends the clean gas to the dryer where its moisture is absorbed. 
4. Now, this clean and dry gas is sent to the mixing chamber where the abrasive particles are found in the abrasive feeder.  (abrasive particles are about 10 to 50 micrometer bit size)
5. Now, these high pressure (about 850 kPa)  abrasive particles and gas are sent to the nozzle (the nozzle diameter ranges from about 0.18 to 0.80 mm), where its pressure energy is converted into kinetic energy.
6. The velocity of the abrasive particles leaving the nozzle ranges from about 150 to 300 m/s.
7. The distance between the workpiece and the nozzle (tungsten) is about 2 mm. 
8. Now, these high velocity abrasive particles are strikes on the workpiece. These high velocity abrasive particles remove the material through micro-cutting action as well as by brittle fractures of the work material.

Application of Abrasive Jet Machining:

1. It is used in the drilling and cutting of hard metals. 
2. It is used for machining brittle and heat sensitive materials like glass, mica, ceramic, sapphire, quartz, etc. 
3. It is used for manufacturing electronic components. 

Advantages of Abrasive Jet Machining:

1. High surface finish. 
2. It can machine heat sensitive material.
3. It is free from vibration.  
4. The initial cost is low compared to other non-traditional procedures. 
5. Thin sections can be made easily.

Disadvantages of Abrasive Jet Machining :

1. Low metal removal rate. 
2. Nozzle life is limited, so it needs to be replaced frequently. 
3. The abrasive particle cannot be reused in this process. 
4. This machine can not use for a soft and ductile material.

FOR DAILY CIVIL ENGINEERING JOBS UPDATE VISIT

Join Our Whatsapp Group