12-08-2013, 05:00 PM
PRESENTATION ON ABRASIVE WATER JET MACHINING
ABRASIVE WATER .ppt (Size: 1.34 MB / Downloads: 74)
History
Dr. Franz in 1950’s first studied UHP water cutting for forestry and wood cutting (pure WJ)
1979 Dr. Mohamed Hashish added abrasive particles to increase cutting force and ability to cut hard materials including steel, glass and concrete (abrasive WJ)
First commercial use was in automotive industry to cut glass in 1983
Soon after, adopted by aerospace industry for cutting high-strength materials like Inconel, stainless steel and titanium as well as composites like carbon fiber
Pure WJ Cutting
Pure cuts soft materials – corrugated cardboard, disposable diapers, tissue papers, automotive interiors
Very thin stream (0.004-0.010 dia)
Extremely detailed geometry
Very little material loss due to cutting
Can cut thick, soft, light materials like fiberglass insulation up to 24” thick or thin, fragile materials
Very low cutting forces and simple fixturing
Water jet erodes work at kerf line into small particles
Abrasive WJ Cutting
Used to cut much harder materials
Water is not used directly to cut material as in Pure, instead water is used to accelerate abrasive particles which do the cutting
80-mesh garnet (sandpaper) is typically used though 50 and 120-mesh is also used
Standoff distance between mixing tube and workpart is typically 0.010-0.200 – important to keep to a minimum to keep a good surface finish
BASIC WORKING :
A water jet cutter, also known as a water jet, is a tool capable of slicing into metal or other materials (such as granite) using a jet of water at high velocity and pressure, or a mixture of water and an abrasive substance. The process is essentially the same as water erosion found in nature but greatly accelerated and concentrated. It is often used during fabrication or manufacture of parts for machinery and other devices. It is the preferred method when the materials being cut are sensitive to the high temperatures generated by other methods. It has found applications in a diverse number of industries from mining to aerospace where it is used for operations such as cutting, shaping, carving and reaming.
Conclusion
Relatively new technology has caught on quickly and is replacing century-old methods for manufacturing
Used not only in typical machining applications, but food and soft-goods industries
As material and pump technology advances faster cutting rates, longer component life and tighter tolerances will be achievable
Paves the way for new machining processes that embrace simplicity and have a small environmental impact