Abrasive jet machining (AJM) is one of the modern machining processes where high velocity jet of abrasives mixed with dehumidified pressurized gas is made. PDF | Abrasive jet machining (AJM) is a manufacturing technology based on erosion localization and intensification. AJM has a progressively. PDF | As Abrasive jet machining (AJM) is similar to sand blasting and effectively removes hard and brittle materials. AJM has been applied to rough working.
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They are used to control the pressure and regulate the flow rate of abrasive jet. A nozzle is used to convert this pressure energy into kinetic energy and also to direct the machinning towards work surface at a particular angle impingement angle. Such cleaning processes include removal of oxide, paint, coating, stain, glue, loose sand particles, etc.
On the other hand, fine abrasives reduce MRR but improve surface quality and accuracy. Functions of nozzle in abrasive jet machining Can you choose AJM nozzle with arbitrary inner diameter?
Abrasive jet machining can be applied for metal surface cleaning like removing oxide or corrosive layer from hard surface. It pressurizes the gas. When conventional machining operation is carried out, some unwanted tiny metal machininh remain attached to the edges after the completion of operation, which are known as burr.
Ahrasive surface finish can be obtained. Apart from above main applications of AJM, it can also be utilized for cutting various shapes as well as for drilling holes.
Abrasive jet machining – Wikipedia
In the mixing chamber, abrasive powder is fed. Such cleaning processes include—. The process can be easily controlled to vary the metal removal rate which depends on flow rate and size of abrasive particles.
Important process parameters include i abrasive particles—its shape, size, strength, material and flow rate; ii carrier gas—its nature, composition, flow rate, pressure and temperature; iii abrasive jet—mixing ratio, striking velocity, impingement angle and stand-off distance; iv nozzle—its profile and inner diameter; and v work material—its mechanical properties and stress concentration. The basic unit is schematically shown in following Figure. AJM should be avoided if work material is soft and ductile; otherwise quality of machined surface will be poor.
Category List Automobile Engineering Biomass Boiling heat transfer energy energy sources engineering materials. Such cleaning processes include— Removal of oxide machiinng corrosive layer from surface Removal of paint or coating layer Removal of stain mark Removal of glue, resin or other adhesive layer Removal of oil, grease or other smear Removal of foreign loose particles including soil Presence of rust on metallic surface can degrade appearance as well as functionality.
Disadvantages of Abrasive Jet Machining: Abrasive jet machining can be advantageously utilized for multifarious purposes including surface cleaning, deburring, abrading and even making holes. Basic purpose of carrier gas in abrasive jet machining is to accelerate fine abrasive particles by momentum transfer.
Formulas for MRR in abrasive jet machining process. Equipment cost is low. Smaller size grits produce highly finished surface but reduce material removal rate MRR and thus productivity descends.
Abrasive-jet Machining (AJM)
Mass flow rate of abrasive is usually controlled by Mixing Ratio, whose effects are also discussed later in this section. Indefinite increase in MRR is not practically feasible because of limited capability of equipment and accessories. It is a mixture of a gas or air and abrasive particles. AJM can also be used for various trimming applications in molding and forging.
Abrasive jet machining AJMalso known as abrasive micro-blastingpencil blasting and micro-abrasive blasting is an abrasive blasting machining process that uses abrasives propelled by a high velocity gas to erode material from the workpiece. Also a good appearance may not be obtained if engraving is carried out by AJM.
Nozzle also directs high velocity jet towards work surface from a specific distance called SOD and at a particular predefined angle, called impingement angle. Glass can also be frosted by abrasive jet machining. AJM is also economic for producing frosted glass glass with pitted surface at one or both sides to reduce transparencyespecially when produced in large scale.
However, holes, slots or pockets may lack accuracy as sharp corners cannot be obtained by this process. This necessitates thicker and stronger pipelines and other accessories to smoothly handle such high pressure without leakage and rupture.
Compressor unit also consists of drier and filter. Nozzle used in abrasive jet machining Primary function of nozzle in abrasive jet machining is to convert pressure energy of the pressurized gas-abrasive mixture into kinetic energy in the form of high velocity jet.
Subscribe in a reader. Different types of welding defects. Typical frosted glass, it reduces transparency. In the mixing chamber, the abrasive is allowed to flow into the gas stream. Every conventional tool-based machining process inherently produces barasive.
The abrasive powder and the compressed air are thoroughly mixed in the chamber.