PowerPoint Presentation: A BRASIVE JET MACHINING What is abrasive jet machining ?: What is abrasive jet machining ? It is the material removal process where the material is removed by high velocity stream of air/gas or water and abrasive mixture . An abrasive is small, hard particle having sharp edges and an irregular shape . High velocity jet is aimed at a surface under controller condition . components of abrasive jet machining: components of abrasive jet machining Abrasive delivery system Control system Pump Nozzle Mixing tube Motion system abrasive delivery system: abrasive delivery system Auto abrasive delivery system has the capability of storing abrasive & delivery the 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 . 2.Control system: 2.Control system The control algorithm that computes exactly how the feed rate should vary for a given geometry in 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 . 3.pump: 3.pump Crankshaft & intensifier pump are mainly use in the abrasive jet machine . The intensifier pump was the only pump capable of reliably creating pressures high . Crankshaft pumps are more efficient than intensifier pumps because they do not require a power robbing hydraulic system ultra high pressure & more stroke per minute . 4.nozzle: 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 by the 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 . Fig. Of nozzle: Fig. Of nozzle 5. Mixing tube: 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 . 6.Motion system: 6.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 working process: 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 from previous cut . fig . schematic diagram of ajm: fig . schematic diagram of ajm ajm features: ajm features There are main features of AJM Obtainable tolerances Material to machine Material thickness Accuracy of table Stability of table Control abrasive jet Machine aspects: Machine aspects Around curves Inside corner Feed rate Acceleration Nozzle focus Speed cutting Pump pressure Hardness & thickness Software controlling the motion Power at the nozzle Types of abrasive materials: Types of abrasive materials Different types of abrasive are used in abrasive jet machining like garnet , aluminum oxide , 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 . Advantages : 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 Disadvantages : Disadvantages Low metal removal rate Due to stay cutting accuracy is affected Abrasive powder cannot be reused Tapper is also a problem conclusion: 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 .