Explaining the process of Abrasive Jet machining

1. BY
ARAVINDKUMAR B

2.  WHAT ISABRASIVE JET MACHINING
 Itis the material removal process where the
materialis removed byhigh velocity streamof
air/gas or water and abrasive mixture .
 An abrasiveis small, hardparticle havingsharp
edges and anirregularshape .
 High velocity jetis aimed atasurface under
controller condition .

3. COMPONENTSOFABRASIVE JET
MACHINING
 Abrasive delivery system
system Control
 Pump
 Nozzle
 Mixing
 Motion
tube
system

4. 1. ABRASIVE DELIVERY SYSTEM
 Auto abrasive delivery system hasthe capability
of storing abrasive &deliverythe abrasive to
the bucket . It’s works auto programming
system by help
of once measuring record &no
adjustment or fine tuning system . High sensitive
sensor gives extremely reliable&repeatable .

5. 2.CONTROL SYSTEM
 The control algorithm that computes exactly
how the feed rate should vary for a given
geometryin a given material to make a precise
part .
The algorithm actually
determines desired variation
in the feed rate &the tool
path to provide an extremely
smooth feed rate .

6. 3.PUMP
 Crankshaft &intensifier pump are mainly use
in the abrasive jet machine .
The intensifier pump was the
only pump capable of reliably
creatingpressures high .
Crankshaft pumps are more
efficient thanintensifierpumps
because they do not require a power robbing
hydraulic system ultra high pressure & more
stroke per minute .

7. 4.NOZZLE
 All abrasive jet systems use the same basic two
stage nozzle . First , water passes through a
small diameter jewel orifice to form a narrow
jet .
 The abrasive particles are accelerated bythe
moving stream of water &they pass into a
long hollow cylindrical
ceramic mixing tube.
 Generally two type of nozzle
use , right angle head &
straight head .

8.  FIG. OF NOZZLE

9. 5. MIXING TUBE
 The mixing tube is where the abrasive mixes
with the high pressure water.
The mixing tube should be
replaced when tolerances
drop below acceptable levels .
 For maximum accuracy,
replace the mixing tube
more frequently .

10. .MOTION SYSTEM
 In order to make precision parts , an abrasive jet
system must have a precision x-y table and
motion control system .
 Tables fall into three general categories .
 Floor-mounted gantry systems
 Integrated table/gantry systems
 Floor-mounted cantilever systems

11.  WORKING PROCESS
 High pressure water starts at the pump , and is
delivered through special high pressure
plumbing to the nozzle .
 At the nozzle , abrasive is introduced & as the
abrasive/water mixture exits , cutting is
performed .
 Once the jet has exited the nozzle , the
energy is dissipated into the catch
tank , which is usually full of water
& debris fromprevious cut .

12.  FIG. SCHEMATIC DIAGRAM OF AJM

13.  AJM FEATURES
of AJM There are main features
 Obtainable tolerances
 Material to machine
 Material
 Accuracy
 Stability
thickness
of table
of table
 Control abrasive jet

14. motion
 MACHINE ASPECTS
 Around curves
 Inside corner
 Feed rate
 Acceleration
 Nozzle focus
 Speed cutting
 Pump pressure
 Hardness & thickness
 Software controlling the
 Power at the nozzle

15.  TYPES OF ABRASIVE MATERIALS
 Different types of abrasive are used in
abrasive jetmachining like garnet ,
aluminumoxide
, olivine , silica sand , silicon carbide ,etc .
 Virtually any material can be cut by using
abrasive jet machining method , i.e harder
materials like titanium to steel.
 Abrasive particles must be hard ,high toughness,
irregular in shape & edges should be sharp .

16.  ADVANTAGES
 Extremely fast setup & programming
 No start hole required
 There is only one tool
 Low capital cost
 Less vibration
 No heat generated in work piece
 Environmentally friendly

17.  DISADVANTAGES
 Low metal removal rate
 Due to stay cutting accuracy is affected
 Abrasive powder cannot be reused
 Tapper is also a problem

18.  CONCLUSION
 The better performance , and the applications
represented above statements confirm that
ABRASIVE JET MACHINING is continue to
expand .
 The new software’s used to minimize time and
investments , there by making it possible for
more manufacturers of precision parts to
install AJM centers .