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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Enter your email address: Carrier gas is also made dust free before compressing to high pressure. Mishra Narosa Publishing House. It is also one application of abrasive jet machining. Irregular shape abrasives having sharp edges tend to produce higher MRR as compared to spherical grits.
The abrasive jet is obtained by accelerating fine abrasive particles in highly pressurized gas carrier gas. Various components of AJM set-up and their functions. However, pure oxygen is not used as it can quickly oxidize the work surface.
Abrasive-jet Machining (AJM)
In the mixing chamber, abrasive powder is fed. In AJM, it is assumed that hard abrasive particles participate in material removal action, while carrier gas assists to blow away eroded particles from machining zone.
Abrasive particles used in abrasive jet machining In AJM, it is assumed that amj abrasive particles participate in material removal action, while carrier gas assists to blow away eroded particles from machining zone. 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.
Abrasive-jet Machining (AJM) – Modern Machining Process
Also a good appearance may not be obtained if engraving is carried out by AJM. However, holes, slots or pockets cut by AJM may lack accuracy as sharp corners cannot be obtained by this process. Finnie ; Some observations on the erosion of ductile metals; Wear; Vol. Effects of abrasives on AJM performance As discussed earlier, shape, size, strength, material and flow rate of abrasive can influence machining performance.
However, ductile and brittle materials behave differently in indent formation, and thus size of indentation created by the impact of single abrasive grit is different for ductile and brittle materials.
The surface machined can have good finish by controlling the grain size mainly. Sometime movement of work table is controlled by servo mechanism. Thus an optimum value of stand-off distance is required to set for obtaining satisfactory performance in abrasive jet machining.
A number of such gauges are employed for measuring pressure of carrier gas as well as gas-abrasive mixture.
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. Nonconventional Machining by P. Normallly inaccessible portion can be machined with good accuracy.
AJM can also be used for various trimming applications in molding and forging.
Abrasive Jet Machining (AJM) «
Typical engraving applications for AJM includes—. Jain Allied Publishers Private Limited.
Non-corrosive abrading of ceramic materials can be carried out by abrasive jet machining AJM. Indefinite increase in MRR is not practically feasible because of limited capability of equipment and accessories.
It is evident that the SOD changes the abrasive particles spreads i. The following are some of the operations that can be performed using Abrasive Jet Machining: Mixing ratio can be increased by increasing abrasive percentage and in such case an increasing trend jer MRR can be noticed because larger number of abrasives participates in micro-cutting action per unit time.
In the mixing chamber, the abrasive is allowed to flow into the gas stream. It pressurizes the gas. AJM utilizes various abrasives including alumina, silicon carbide, glass beads, sodium bicarbonate, etc. How material removal rate can be increased? ApplicationsTexas Airsonics, archived from the original on March 4, Abrasive jet machining can be applied for metal surface abrasivw like removing oxide or corrosive layer from hard surface.
Abrasive jet machining
If you continue to use this site we will assume that you are jeh with it. Basic purpose of carrier gas in abrasive jet machining is to abrasivf fine abrasive particles by momentum transfer. Mild steel is the most commonly used steel. Different Types of Pattern Allowances in Casting. Advanced Machining Processes by V. Such cleaning processes include removal of oxide, paint, coating, stain, glue, loose sand particles, etc.
It is used in the industries as well in the different everyday objects we use. It filters the gas before entering the compressor and mixing chamber. Effects of carrier gas on AJM performance Carrier gas pressure and its flow rate are two paramount factors that determine performance and machining capability.
Carrier gas pressure and its flow rate are two paramount factors that determine performance and machining capability. Such macuining removal mechanism can be advantageously utilized for multifarious purposes abrasvie surface cleaning, deburring, abrading and even making holes.
This necessitates thicker and stronger pipelines and other accessories to smoothly handle such high pressure without leakage and rupture. The harder is the abrasive with respect to work surface hardness, the larger will be the volume removal rate.
Material is removed by fine abrasive particles, usually about 0.
There are some allowances which are responsible for the difference in the dimensions of the casting and the pattern Smooth surface finish can be obtained. The basic unit is schematically shown in following Figure.