عرض كامل الموضوع : water jet cutting

10-12-2006, 02:37 PM
Standard metal cutting processes: laser cutting vs. water jet cutting
Laser manufacturing activities currently include cutting, welding, heat treating, cladding, vapor deposition, engraving, scribing, trimming, annealing, and shock hardening. Laser manufacturing processes compete both technically and economically with conventional and nonconventional manufacturing processes such as mechanical and thermal machining, arc welding, electrochemical, and electric discharge machining (EDM), abrasive water jet cutting, plasma cutting, and flame cutting.

Water jet cutting is a process used to cut materials using a jet of pressurized water as high 60,000 pounds per square inch (psi). Often, the water is mixed with an abrasive like garnet that enables more materials to be cut cleanly to close tolerances, squarely and with a good edge finish. Water jets are capable of cutting many industrial materials including stainless steel, Inconel, titanium, aluminium, tool steel, ceramics, granite, and armor plate. This process generates significant noise.

The table that follows contains a comparison of metal cutting using the CO2 laser cutting process and water jet cutting process in industrial material processing.

Fundamental process differences
Typical process applications and uses
Initial investment and average operating costs
Precision of process
Safety considerations and operating environment
Fundamental process differences

Method of imparting energy
Light 10.6 µm (far infrared range)

Source of energy
Gas laser
High-pressure pump

How energy is transmitted
Beam guided by mirrors (flying optics); fiber-transmission not
feasible for CO2 laser
Rigid high-pressure hoses transmit the energy

How cut material is expelled
Gas jet, plus additional gas expels material
A high-pressure water jet expels waste material

Distance between nozzle and material and maximum permissable tolerance
Approximately 0.2" ± 0.004", distance sensor, regulation and Z-axis necessary
Approximately 0.12" ± 0.04", distance sensor, regulation and Z-axis necessary

Physical machine set-up
Laser source always located inside machine
The working area and pump can be located separately

Range of table sizes
8' x 4' to 20' x 6.5'
8' x 4' to 13' x 6.5'

Typical beam output at the workpiece
1500 to 2600 Watts
4 to 17 kilowatts (4000 bar)