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Contemporary Machining Processes
Among the various classifications of waterjet cutting heads, the following can be
recommended (Korzhov, 2006):
1. Dynamically improved cutting heads equipped with special structural
elements
2. Abrasive waterjet cutting heads, where the most feasible designs are able to
introduce the abrasive slurry into the water jet with a minimal distortion of
its hydrodynamic characteristics
3. Combined nozzle heads, such as dual-head or double-head systems, where
up to four cutting heads can work simultaneously
According to the system configuration, jet tools can also be categorized by their
phase composition (Bergs et al., 2020):
1. Standard PWJ (one-phase – water)
2. Injection PWJ (two-phase – water, air)
3. Suspension AWJ (two-phase – water, abrasive)
4. Injection AWJ (three-phase – water, abrasive, air)
High-pressure distribution system. Waterjet cutting systems work with a very high
water pressure of 400 MPa. The jet leaves the cutting nozzle at 1,000 m/s, which is
three times the speed of sound. The pump must be protected from cavitation and the
pressure must be delivered from the pump to the cutting head. Fixed and movable
pipelines are applied together with special high-pressure hinges or specially shaped
spiral tubes.
Abrasive hooper. Korzhov (2006) specifies two main systems delivering abrasive
powder to the mixing chamber of the cutting head, namely based on vacuum or air
pressure. The vacuum system works as a pulverizer, while in the latter the powder is
forced into the mixing chamber by pressurized air.
1.12.3 main advanTages of awj machining
Lack of thermal distortion, high machining versatility, high flexibility, and small
cutting forces are among the most distinct advantages of AWJ machining. No electrical or thermal energy is used, therefore, many material defects can be ignored
(Saravanan et al., 2020). Korzhov (2006) emphasizes the following benefits:
• Elimination of thermal impact due to a continuous cooling effect of the
water jet. No significant rise in workpiece temperature is noted, which is
a decisive factor in the machining of thermosensitive materials. Cutting
forces of between 1 and 100 N and temperatures between +60 and +90°С
in the cutting area eliminate any deformations of the workpiece. It should
be noted that no other technique can be performed without thermal effects
on metals.
Contemporary Machining Processes
Among the various classifications of waterjet cutting heads, the following can be
recommended (Korzhov, 2006):
1. Dynamically improved cutting heads equipped with special structural
elements
2. Abrasive waterjet cutting heads, where the most feasible designs are able to
introduce the abrasive slurry into the water jet with a minimal distortion of
its hydrodynamic characteristics
3. Combined nozzle heads, such as dual-head or double-head systems, where
up to four cutting heads can work simultaneously
According to the system configuration, jet tools can also be categorized by their
phase composition (Bergs et al., 2020):
1. Standard PWJ (one-phase – water)
2. Injection PWJ (two-phase – water, air)
3. Suspension AWJ (two-phase – water, abrasive)
4. Injection AWJ (three-phase – water, abrasive, air)
High-pressure distribution system. Waterjet cutting systems work with a very high
water pressure of 400 MPa. The jet leaves the cutting nozzle at 1,000 m/s, which is
three times the speed of sound. The pump must be protected from cavitation and the
pressure must be delivered from the pump to the cutting head. Fixed and movable
pipelines are applied together with special high-pressure hinges or specially shaped
spiral tubes.
Abrasive hooper. Korzhov (2006) specifies two main systems delivering abrasive
powder to the mixing chamber of the cutting head, namely based on vacuum or air
pressure. The vacuum system works as a pulverizer, while in the latter the powder is
forced into the mixing chamber by pressurized air.
1.12.3 main advanTages of awj machining
Lack of thermal distortion, high machining versatility, high flexibility, and small
cutting forces are among the most distinct advantages of AWJ machining. No electrical or thermal energy is used, therefore, many material defects can be ignored
(Saravanan et al., 2020). Korzhov (2006) emphasizes the following benefits:
• Elimination of thermal impact due to a continuous cooling effect of the
water jet. No significant rise in workpiece temperature is noted, which is
a decisive factor in the machining of thermosensitive materials. Cutting
forces of between 1 and 100 N and temperatures between +60 and +90°С
in the cutting area eliminate any deformations of the workpiece. It should
be noted that no other technique can be performed without thermal effects
on metals.