REDUCED SCALE NOZZLES FOR PLASMA TORCH AND ADAPTER FOR THE NOZZLES

Abstract

Reduced scale nozzles for current loads of up to 400 A to be used in a liquid-cooled dual-gas plasma torch. The plasma flow passes through aperture in nozzle in direction. Aperture is divergent and expands in direction of the plasma flow. Aperture is of a conical shape at point, radius shape at point, and elliptic shape at point. Following its narrowest section, aperture expands at angle in direction of the plasma flow. Diameter at the end of aperture is larger than diameter at its beginning. Nozzle is equipped with mounting surface for insertion into the adapter. Nozzle contains seal, which prevents passage of a liquid and gas through the connection between nozzle and the adapter, which also provides attachment to the plasma torch.

Claims

1-20. (canceled)

21. A reduced scale nozzle suitable for use in a liquid-cooled dual-gas plasma torch, which nozzle is suitable to be directly cooled by a liquid coolant, wherein the reduced scale nozzle is adapted for attaching to the liquid-cooled dual-gas plasma torch by means of an adapter, wherein the reduced scale nozzle is provided with a mounting surface for securing the reduced scale nozzle in said plasma torch, wherein for use at current loads of up to 130 A the reduced scale nozzle has the largest outside diameter at least 12.3 mm, wherein for use at current over 130 A the reduced scale nozzle has the largest outside diameter at least 13.5 mm, wherein the reduced scale nozzle has a convergent area and a divergent area, and wherein the divergent area contains an aperture for passage of the plasma flow.

22. The reduced scale nozzle according to claim 1, for use at current loads of up to 130 A, wherein the largest outside diameter is between 12.3 mm and 15.9 mm.

23. The reduced scale nozzle according to claim 2, further comprising: a cooling surface for direct cooling by a liquid coolant.

24. A reduced scale nozzle suitable for use in a liquid-cooled dual-gas plasma torch, which nozzle is suitable to be indirectly cooled by a liquid coolant, wherein the reduced scale nozzle is adapted for attaching to the liquid-cooled dual-gas plasma torch by means of an adapter, wherein the reduced scale nozzle is provided with a mounting surface for securing the reduced scale nozzle in said plasma torch, wherein for use at current loads of up to 400 A, a largest outside diameter is between 18 mm and 25.9 mm.

25. The reduced scale nozzle according to claim 4, further comprising: a cooling surface for indirect cooling.

26. The reduced scale nozzle according to claim 5, wherein the aperture has, sequentially in the direction of the plasma flow, a conical shape section, followed by a cylindrical shape section and ending with a section having a rounded profile.

27. The reduced scale nozzle according to claim 6, wherein the aperture expands conically behind its narrowest point in the direction of the plasma flow at angle ranges from 0.5° to 3.0°.

28. The reduced scale nozzle according to claim 5, wherein the aperture is of a cylindrical shape.

29. The reduced scale nozzle according to claim 8, further comprising: apertures for letting out some of the plasma gas from the convergent area to the outer surface of the reduced scale nozzle for admission into a shielding gas.

30. The reduced scale nozzle according to claim 9, wherein the reduced scale nozzle is made of a copper alloy.

31. The reduced scale nozzle according to claim 10, wherein all of the surfaces of the reduced scale nozzle are galvanically plated with a layer of chromium or nickel 0.008 to 0.012 mm thick.

32. The reduced scale nozzle according to claim 11, further comprising: a seal for preventing passage of liquid and/or gas through the connection between the reduced scale nozzle and the adapter.

33. A combination of the reduced scale nozzle and the adapter according to claim 12, wherein the adapter is provided on its first side with a mounting area for insertion of the reduced scale nozzle and on its second side with a shaping for insertion into the body of a plasma torch, wherein the adapter is fitted with a seal for enabling sealed attaching to said plasma torch, and the connection between the adapter and the reduced scale nozzle on its side is sealed with a seal to prevent passage of liquid and/or gas, wherein the connection between the adapter and the reduced scale nozzle is freely dismountable.

34. A combination of the reduced scale nozzle and the adapter according to claim 13, wherein the adapter is provided on its first side with a mounting area for insertion of the reduced scale nozzle and on its second side with a shaping for insertion into the body of a plasma torch, wherein the adapter is fitted with a seal for enabling sealed attaching to said plasma torch, and the connection between the adapter and the reduced scale nozzle on its side is sealed with a seal to prevent passage of liquid and/or gas, wherein the connection between the adapter and the reduced scale nozzle is freely dismountable, wherein the seal is direct component of the adapter.

35. The combination of the reduced scale nozzle and the adapter according to claim 13, wherein the adapter is made of brass,

36. The reduced scale nozzle according to claim 1, wherein the reduced scale nozzle suitable for use in a liquid-cooled dual-gas plasma torch, which nozzle is suitable to be indirectly cooled by a liquid coolant, wherein the reduced scale nozzle is adapted for attaching to the liquid-cooled dual-gas plasma torch by means of an adapter, wherein the reduced scale nozzle is provided with a mounting surface for securing the reduced scale nozzle in said plasma torch, wherein for use at current loads of up to 400 A, the largest outside diameter is between 18 mm and 25.9 mm.

37. The reduced scale nozzle according to claim 1, wherein the aperture has, sequentially in the direction of the plasma flow, a conical shape section, followed by a cylindrical shape section and ending with a section having a rounded profile.

38. The reduced scale nozzle according to claim 6, wherein the aperture expands conically behind its narrowest point in the direction of the plasma flow at angle ranges from 1.8 to 2.2°.

39. The reduced scale nozzle according to claim 9, wherein the reduced scale nozzle is made of Cu-ETP CW004A or Cu—OF CW008A/EN 13601.

40. The combination of the reduced scale nozzle and the adapter according to claim 13, wherein the adapter is made from alloy ENCW617N/CuZn40Pb2.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Additional details of the invention are provided in the drawings, where:

[0048] FIG. 1 shows a nozzle according to the state of the art known from U.S. Pat. No. 5,317,126,

[0049] FIG. 2 shows a nozzle according to the state of the art known from EP 2104739,

[0050] FIG. 3 shows a nozzle according to the state of the art known from EP 1531652,

[0051] FIG. 4 shows a section of a liquid-cooled dual-gas torch with a reduced scale nozzle, illustrating the fitting of the adapter and the reduced scale nozzle into the plasma torch,

[0052] FIG. 5 shows a section of the reduced scale nozzle for the load of 260 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled directly by a liquid coolant and is fitted with a divergent aperture,

[0053] FIG. 6 shows a section of the reduced scale nozzle for the load of 260 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled by a liquid coolant indirectly and is fitted with a divergent aperture,

[0054] FIG. 7c shows a section of an alternative design of the reduced scale nozzle for the load of 260 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled directly by a liquid coolant and is fitted with a divergent aperture,

[0055] FIG. 7d shows a section of an alternative design of the reduced scale nozzle for the load of 130 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled directly by a liquid coolant and is fitted with a divergent aperture,

[0056] FIG. 7e shows a section of the reduced scale nozzle for the load of 30 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled directly by a liquid coolant and is fitted with a cylindrical aperture,

[0057] FIG. 7f shows a section of an alternative design of the reduced scale nozzle for the load of 30 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled directly by a liquid coolant and is fitted with a cylindrical aperture,

[0058] FIG. 8g shows a section of the reduced scale nozzle for the load of 30 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled by a liquid coolant indirectly and is fitted with a cylindrical aperture,

[0059] FIG. 8h shows a section of an alternative design of the reduced scale nozzle for the load of 130 A designed for use in a liquid-cooled dual-gas plasma torch, where the nozzle is cooled by a liquid coolant indirectly and is fitted with a cylindrical aperture,

[0060] FIG. 9a shows a section of the adapter designed for fitting the reduced scale nozzle into a plasma torch,

[0061] FIG. 9b shows a section of an alternative adapter designed for fitting the reduced scale nozzle into a plasma torch,

[0062] FIG. 9c shows a section of an alternative adapter designed for fitting the reduced scale nozzle into a plasma torch,

[0063] FIG. 9d shows a section of an alternative adapter designed for fitting the reduced scale nozzle into a plasma torch,

[0064] FIG. 9e shows a section of an alternative adapter designed for fitting the reduced scale nozzle into a plasma torch,

[0065] FIG. 9f shows a section of an alternative adapter designed for fitting the reduced scale nozzle into a plasma torch,

[0066] FIG. 10 shows a combination of the reduced scale nozzle according to FIG. 5 and its adapter as compared to a nozzle according to the known state of the art,

[0067] FIG. 11 shows a combination of the reduced scale nozzle according to FIG. 6 and its adapter as compared to a nozzle according to the known state of the art,

[0068] FIG. 12 shows a combination of the reduced scale nozzle according to FIG. 7c and its adapter as compared to a nozzle according to the known state of the art,

[0069] FIG. 13 shows a combination of the reduced scale nozzle according to FIG. 7d and its adapter as compared to a nozzle according to the known state of the art,

[0070] FIG. 14 shows a combination of the reduced scale nozzle according to FIG. 7d and an alternative adapter as compared to a nozzle according to the known state of the art,

[0071] FIG. 15 shows a combination of the reduced scale nozzle according to FIG. 7e and its adapter as compared to a nozzle according to the known state of the art,

[0072] FIG. 16 shows a combination of the reduced scale nozzle according to FIG. 7f and its adapter as compared to a nozzle according to the known state of the art,

[0073] FIG. 17 shows a combination of the reduced scale nozzle according to FIG. 8g and its adapter as compared to a nozzle according to the known state of the art, and

[0074] FIG. 18 shows a combination of the reduced scale nozzle according to FIG. 8h and its adapter as compared to a nozzle according to the known state of the art.

MODES FOR CARRYING OUT THE INVENTION

Embodiment 1

[0075] Reduced scale nozzle 100 according to FIGS. 5 and 10 for the load of 260 A designed for use in a liquid-cooled dual-gas plasma torch. In this torch, the nozzle is cooled by a liquid coolant directly. The liquid cools the electrode and the torch body.

[0076] In nozzle 100, there is aperture 101, through which the plasma flow passes in direction V. Aperture 101 is divergent and expands in direction V of the plasma flow. Aperture 101 is of a conical shape at point 105, radius shape at point 106, and elliptic shape at point 108. Following its narrowest section 104, aperture 101 expands at angle A° equal to 2° in direction V of the plasma flow.

[0077] In area X, the energy of the electric arc is used to ionize the compressed gas, dissociating it. The ionized gas is condensed/concentrated when it passes through the narrowest point 104. In area Y, the plasma flow is already concentrated, with its volume expanding because of the dissociation process. Diameter D4 at the end of aperture 101 is larger than diameter D1 at its beginning. Because aperture 101 expands in direction V, the friction of the plasma flow on the walls is reduced at points 105, 106, and 108. Furthermore, the plasma arc heat loss has been reduced at points 105, 106, and 108, as well as the heat exposure of nozzle 100 at the same places.

[0078] Area X is 3 mm long, while area Y is 6 mm long. At its beginning, aperture 101 has diameter D1 of 2.0 mm. The ratio between the length of area Y and diameter D1 is 3:1. Length L1 equals 4.5 times diameter D1.

[0079] Nozzle 100 is equipped with mounting surface 110 for insertion into adapter 200. Nozzle 100 contains seal 109, which prevents passage of a liquid and gas through the connection between nozzle 100 and adapter 200.

[0080] Nozzle 100 is cooled by a liquid coolant on its surface 103. Distance L2 between cooled surface 103 and the beginning of aperture 101 is 4.77 mm, while distance L3 between cooled surface 103 and the end of aperture 101 is 8.68 mm. Nozzle 100 also contains 3 apertures 102 to let out some of the plasma gas into the shielding gas.

[0081] Nozzle 100 is connected to plasma torch 300 by adapter 200 according to FIG. 9a, which is made of CuZn40Pb2/EN CW617N. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and furthermore it is provided with seal 209 at the point where adapter 200 is attached to torch 300. The connection between nozzle 100 and adapter 200 is freely dismountable, wherein the seal 109 is placed between these parts to prevent passage of a liquid and gas through the connection between nozzle 100 and adapter 200. Seal 109 is a part of nozzle 100. Seal 109 can be placed at any contact area between nozzle 100 and adapter 200.

Embodiment 2

[0082] Reduced scale nozzle 120 according to FIGS. 6 and 11 for the load of 260 A designed for use in a liquid-cooled dual-gas plasma torch. In this torch, the plasma nozzle is cooled by a liquid coolant indirectly. The liquid cools the electrode and the torch body.

[0083] In nozzle 120, there is aperture 101, through which the plasma flow passes in direction V. Aperture 101 is divergent and expands in direction V of the plasma flow. Aperture 101 is of a conical shape at point 105, radius shape at point 106, and elliptic shape at point 108. Following its narrowest section 104, aperture 101 expands at angle A° equal to 2° in direction V of the plasma flow.

[0084] In area X, the energy of the electric arc is used to ionize the compressed gas, dissociating it. The ionized gas is condensed/concentrated when it passes through the narrowest point 104. In area Y, the plasma flow is already concentrated, with its volume expanding because of the dissociation process. Diameter D4 at the end of aperture 101 is larger than diameter D1 at its beginning. Because aperture 101 expands in direction V, the friction of the plasma flow on the walls is reduced at points 105, 106, and 108. Furthermore, the plasma arc heat loss has been reduced at points 105, 106, and 108, as well as the heat exposure of nozzle 120 at the same places.

[0085] Area X is 6 mm long, while area Y is 5 mm long. At its beginning, aperture 101 has diameter D1 of 2.0 mm. The ratio between the length of area Y and diameter D1 is 2.5:1. Length L1 equals 5.5 times diameter D1.

[0086] Nozzle 120 is provided with mounting surface 110 for insertion into adapter 200 and with surface 123, where nozzle 120 touches adapter 200. Nozzle 120 is cooled by means of surface 123, with the cooler adapter 200 receiving the heat from the hotter nozzle 120. Experiments established that the minimum necessary area of surface 123 is 0.80 mm.sup.2 per ampere. Nozzle 120 contains seal 109, which prevents passage of a liquid and gas through the connection between nozzle 100 and adapter 200.

[0087] Nozzle 120 is connected to plasma torch 300 by adapter 200 according to FIG. 9b, which is made of CuZn40Pb2/EN CW617N. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and furthermore it is provided with seal 209 at the point where adapter 200 is attached to torch 300. The connection between nozzle 100 and adapter 200 is freely dismountable, wherein the seal 109 is placed between these parts to prevent passage of a liquid and gas. Seal 109 is a part of nozzle 100. Seal 109 can be placed at any contact area between nozzle 100 and adapter 200.

Embodiment 3

[0088] Reduced scale nozzle 100 according to FIGS. 7c and 12 for the load of 260 A designed for use in a liquid-cooled dual-gas plasma torch. In this torch, the nozzle is cooled by a liquid coolant directly. The liquid cools the electrode and the torch body.

[0089] In nozzle 100, there is aperture 101, through which the plasma flow passes in direction V. Aperture 101 is divergent and expands in direction V of the plasma flow. Aperture 101 is of a conical shape at point 105, radius shape at point 106, and elliptic shape at point 108. Following its narrowest section 104, aperture 101 expands at angle A° equal to 2° in direction V of the plasma flow.

[0090] Area X is the convergent part of the nozzle, while area Y is the divergent part of the nozzle. In area X, the energy of the electric arc is used to ionize the compressed gas, dissociating it. The ionized gas is condensed/concentrated when it passes through the narrowest point 104. In area Y, the plasma flow is already concentrated, with its volume expanding because of the dissociation process. Diameter D4, at the end of aperture 101, is larger than diameter D1 at its beginning. Because aperture 101 expands in direction V, the friction of the plasma flow on the walls of nozzle 100 is reduced at points 105, 106, and 108. By this, we have achieved reduced deposition of the material burnt out of the electrode on the walls of nozzle 100 at points 105, 106, and 108. Furthermore, the plasma arc heat loss has been reduced at points 105, 106, and 108, as well as the heat exposure of nozzle 100 at the same places.

[0091] Area X is 3 mm long, while area Y is 6 mm long. At its beginning, aperture 101 has diameter D1 of 2.0 mm. The ratio between the length of area Y and diameter D1 is 3:1. Length L1 equals 4.5 times diameter D1.

[0092] Nozzle 100 is equipped with mounting surface 110 for insertion of adapter 200.

[0093] Nozzle 100 is cooled by a liquid coolant on its surface 103. Distance L2 between cooled surface 103 and the beginning of aperture 101 is 4.62 mm, while distance L3 between cooled surface 103 and the end of aperture 101 is 8.74 mm.

[0094] Nozzle 100 is connected to plasma torch 300 by adapter 200 according to FIG. 9e, which is made of CuZn40Pb2/EN CW617N. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and furthermore it is provided with seal 209 at the point where adapter 200 is attached to torch 300. The connection between nozzle 100 and adapter 200 is freely dismountable, wherein the seal 109 is placed between these parts to prevent passage of a liquid and gas through the connection between nozzle 100 and adapter 200. Seal 109 can be placed at any contact area between nozzle 100 and adapter 200.

Embodiment 4

[0095] Reduced scale nozzle 100 according to FIGS. 7d and 13 for the load of 130 A designed for use in a liquid-cooled dual-gas plasma torch. In this torch, the nozzle is cooled by a liquid coolant directly. The liquid cools the electrode and the torch body.

[0096] In nozzle 100, there is aperture 101, through which the plasma flow passes in direction V. Aperture 101 is divergent and expands in direction V of the plasma flow. Aperture 101 is of a conical shape at point 105, radius shape at point 106, and elliptic shape at point 108. Following its narrowest section 104, aperture 101 expands at angle A° equal to 2° in direction V of the plasma flow.

[0097] Area X is the convergent part of the nozzle, while area Y is the divergent part of the nozzle. In area X, the energy of the electric arc is used to ionize the compressed gas, dissociating it. The ionized gas is condensed/concentrated when it passes through the narrowest point 104. In area Y, the plasma flow is already concentrated, with its volume expanding because of the dissociation process. Diameter D4 at the end of aperture 101 is larger than diameter D1 at its beginning. Because aperture 101 expands in direction V, the friction of the plasma flow on the walls of nozzle 100 is reduced at points 105, 106, and 108. By this, we have achieved reduced deposition of the material burnt out of the electrode on the walls of nozzle 100 at points 105, 106, and 108. Furthermore, the plasma arc heat loss has been reduced at points 105, 106, and 108, as well as the heat exposure of nozzle 100 at the same places.

[0098] Area X is 2.1 mm long, while area Y is 4.2 mm long. At its beginning, aperture 101 has diameter D1 of 1.4 mm. The ratio between the length of area Y and diameter D1 is 3:1. Length L1 equals 4.5 times diameter D1.

[0099] Nozzle 100 is equipped with mounting surface 110 for insertion of adapter 200. Nozzle 100 contains seal 109, which prevents passage of a liquid and gas through the connection between nozzle 100 and adapter 200.

[0100] Nozzle 100 is cooled by a liquid coolant on its surface 103. Distance L2 between cooled surface 103 and the beginning of aperture 101 is 4.75 mm, while distance L3 between cooled surface 103 and the end of aperture 101 is 7.02 mm.

[0101] Nozzle 100 was sufficiently galvanically plated with a layer of chromium 0.008 to 0.012 mm thick.

[0102] Nozzle 100 is connected to plasma torch 300 by adapter 200, which is made of CuZn40Pb2/EN CW617N. Adapter 200 employed in this embodiment is of type “d” according to FIG. 9d. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and furthermore it is provided with seal 209 at the point where adapter 200 is attached to torch 300. The connection between nozzle 100 and adapter 200 is freely dismountable, with seal 109 placed between these parts to prevent passage of a liquid and gas through the connection between nozzle 100 and adapter 200. Seal 109 can be placed at any contact area between nozzle 100 and adapter 200.

Embodiment 5

[0103] Reduced scale nozzle 100 according to FIGS. 7d and 14, the same as the nozzle in embodiment 4, with one difference: instead of additional galvanic plating with a layer of chromium, it has been plated with a layer of nickel 0.008 to 0.012 mm thick.

[0104] Nozzle 100 is connected to plasma torch 300 by adapter 200, which is made of CuZn40Pb2/EN CW617N. Adapter 200 employed in this embodiment is of type “f” according to FIG. 9f On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and furthermore it is provided with seal 209 at the point where adapter 200 is attached to torch 300. The connection between nozzle 100 and adapter 200 is freely dismountable, with seal 109 placed between these parts to prevent passage of a liquid and gas through the connection between nozzle 100 and adapter 200. Seal 109 can be placed at any contact area between nozzle 100 and adapter 200.

Embodiment 6

[0105] Reduced scale nozzle 100 according to FIGS. 7e and 15 for the load of 30 A designed for use in a liquid-cooled dual-gas torch. In this torch, the plasma nozzle is cooled directly by a liquid coolant. The liquid cools the electrode and the torch body.

[0106] The plasma flow passes through aperture 121 in nozzle 100 in direction V. Aperture 121 has a cylindrical shape. In aperture 121, the energy of the electric arc is used to ionize the compressed gas, which dissociates because of the energy of the electric arc. The ionized gas is condensed/concentrated when entering aperture 121.

[0107] Area X is 1.6 mm long, while area Y is 1.6 mm long. At its beginning, aperture 121 has diameter D1 of 0.65 mm. The ratio between the length of area Y and diameter D1 is 2.46:1. Length L1 equals 4.92 times diameter D1.

[0108] Nozzle 100 is equipped with mounting surface 110 for insertion into adapter 200. Nozzle 100 contains seal 109, which prevents passage of a liquid and gas through the connection between nozzle 100 and adapter 200.

[0109] Nozzle 100 is cooled by a liquid coolant on its surface 103. Distance L2 between cooled surface 103 and the beginning of aperture 121 is 5.14 mm, while distance L3 between cooled surface 103 and the end of aperture 121 is 6.48 mm.

[0110] Nozzle 100 is connected to plasma torch 300 by adapter 200 according to FIG. 9a, which is made of CuZn40Pb2/EN VW617N. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion of the body of torch 300, and also it is provided with seal 209 at the point where adapter 200 is attached to torch 300. The connection between nozzle 100 and adapter 200 is freely dismountable, wherein the seal 109 placed between these parts to prevent passage of a liquid and gas through the connection. Seal 109 is a part of nozzle 100. The seal can be placed at any contact area between nozzle 100 and adapter 200.

Embodiment 7

[0111] Reduced scale nozzle 100 according to FIGS. 7f and 16 for the load of 130 A designed for use in a liquid-cooled dual-gas plasma torch. In this torch, the plasma nozzle is cooled directly by a liquid coolant. The liquid cools the electrode and the torch body.

[0112] The plasma flow passes through aperture 121 in nozzle 100 in direction V. Aperture 121 has a cylindrical shape. In the cylindrical part of nozzle 100, the energy of the electric arc is used to ionize the compressed gas, which dissociates because of the energy of the electric arc. The ionized gas is condensed/concentrated when entering aperture 121.

[0113] Area X is 3.6 mm long, while area Y is 3.6 mm long. The diameter of aperture 121 is 1.45 mm. The ratio between the length of area Y and the diameter of aperture 121 is 2.5:1. Length L1 equals 5 times the diameter of aperture 121.

[0114] Nozzle 100 is equipped with mounting surface 110 for insertion into adapter 200.

[0115] Nozzle 100 is on its surface 103 cooled by a liquid, wherein the distance L2 between cooled surface 103 and the beginning of aperture 121 being 4.73 mm, and distance L3 between cooled surface 103 and the end of aperture 121 being 7.05 mm. Nozzle 100 also contains 3 apertures 102 to let out some of the plasma gas into the shielding gas.

[0116] Nozzle 100 is connected to plasma torch 300 by adapter 200 according to FIG. 9c, which is made of CuZn40Pb2/EN CW617 N. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and also it is provided with seal 209 at the point where adapter 200 is attached to torch 300. Seal 109 is placed at the freely dismountable connection between nozzle 100 and adapter 200 to prevent passage of a liquid and gas. Seal 109 is a part of adapter 200. Seal 109 can be placed at any contact area between nozzle 100 and adapter 200.

Embodiment 8

[0117] Reduced scale nozzle 120 according to FIGS. 8g and 17 for the load of 30 A designed for use in a liquid-cooled dual-gas plasma torch. In this torch, the plasma nozzle is not cooled by a liquid coolant directly. The liquid cools the electrode and the torch body.

[0118] The plasma flow passes through aperture 121 in nozzle 120 in direction V. Aperture 121 has a cylindrical shape. In the cylindrical part of nozzle 120, the energy of the electric arc is used to ionize the compressed gas, which dissociates because of the energy of the electric arc. The ionized gas is condensed/concentrated when entering aperture 121.

[0119] Area X is 6.86 mm long, while area Y is 1.4 mm long. The diameter of aperture 121 is 0.7 mm. The ratio between the length of area Y and the diameter of aperture 121 is 2:1. Length L1 equals 11.8 times the diameter of aperture 121.

[0120] Nozzle 120 is provided with mounting surface 110 for insertion into adapter 200 and with surface 123, where nozzle 120 touches adapter 200. Nozzle 120 is cooled by means of surface 123, with the cooler adapter 200 receiving the heat from the hotter nozzle 120. Experiments established that the minimum necessary area of surface 123 is 7.45 mm.sup.2 per ampere. Nozzle 120 contains seal 109, which prevents passage of a gas through the connection between nozzle 120 and adapter 200. Nozzle 120 also contains 2 apertures 102 to let out some of the plasma gas into the shielding gas.

[0121] Nozzle 120 is connected to plasma torch 300 by adapter 200 according to FIG. 9b, which is made of CuZn40Pb2/EN CW617N. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 100, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and furthermore it is provided with seal 209 at the point where adapter 200 is attached to torch 300. Seal 109 is placed at the freely dismountable connection between nozzle 120 and adapter 200 to prevent passage of a liquid and gas. Seal 109 is a part of nozzle 120. Seal 109 can be placed at any contact area between nozzle 120 and adapter 200.

Embodiment 9

[0122] Reduced scale nozzle 120 according to FIGS. 8h and 18 for the load of 130 A designed for use in a liquid-cooled dual-gas plasma torch. In this torch, the plasma nozzle is not cooled by a liquid coolant directly. The liquid cools the electrode and the torch body.

[0123] The plasma flow passes through aperture 121 in nozzle 120 in direction V. Aperture 121 has a cylindrical shape. In the cylindrical part of nozzle 120, the energy of the electric arc is used to ionize the compressed gas, which dissociates because of the energy of the electric arc. The ionized gas is condensed/concentrated when entering aperture 121.

[0124] Area X is 5.6 mm long, while area Y is 2.8 mm long. The diameter of aperture 121 is 1.4 mm. The ratio between the length of area Y and the diameter of aperture 121 is 2.0:1. Length L1 equals 6.0 times diameter D1.

[0125] Nozzle 120 is provided with mounting surface 110 for insertion into adapter 200 and with surface 123, where nozzle 120 touches adapter 200. Nozzle 120 is cooled by means of surface 123, with the cooler adapter 200 receiving the heat from the hotter nozzle 120. Experiments established that the minimum necessary area of surface 123 is 1.72 mm.sup.2 per ampere. Nozzle 120 contains seal 109, which prevents passage of a liquid and gas through the connection between nozzle 120 and adapter 200.

[0126] Nozzle 120 is connected to plasma torch 300 by adapter 200 according to FIGS. 9b and 18, which is made of CuZn40Pb2/EN CW617 N. On its side 202, adapter 200 is provided with a seat for insertion of nozzle 120, while on its side 201, it is provided with a shaping for insertion into the body of torch 300, and also it is provided with seal 209 at the point where adapter 200 is attached to torch 300. Seal 109 is placed at the freely dismountable connection between nozzle 120 and adapter 200 to prevent passage of a liquid and gas. Seal 109 is a part of nozzle 120. Seal 109 can be placed at any contact area between nozzle 120 and adapter 200.

[0127] In order to compare the effects achieved by reduced scale nozzles according to the submitted invention against commercially available nozzles (state of the art), a series of comparative experiments have been carried out, as listed below.

Comparative Experiment 1

[0128] To test reduced scale nozzles 100 for the load of 260 A, we used type “a” reduced scale plasma nozzle 100 according to FIGS. 5 and 10. Nozzle 100 had the outside diameter D2 of 15.70 mm, while commercially available nozzle 11 (HPR 400 XD®, by Hypertherm®), whose design matches U.S. Pat. No. 5,317,126, had the outside diameter of 26.85 mm. Nozzle 100 was made of Cu—OF CW008/EN 13601 and at the load of 260 A its average lifespan was 42% longer than that of commercial nozzle 11, made of CuTeP CW118C.

[0129] Adapter 200 employed in this experiment was of type “a” according to FIG. 9a. After nozzle 100 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 100 with a brand new nozzle 100. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 100 were consumed. Nozzle 100 withstood the concentrated load of 82.8 A per mm.sup.2 of the cross-section of aperture 101. Upon comparing the manufacturing cost of 20 pcs of nozzles 11 for the load of 260 A against the manufacturing cost of 20 pcs of reduced scale nozzles 100 of type “a” for the load of 260 A plus 1 pc of type “a” adapter 200, it was established that for the solution according to the submitted invention, the material consumption was reduced by 75.5% and the manufacturing time was reduced by 5%.

Comparative Experiment 2

[0130] To test reduced scale nozzles 120 for the load of 260 A, we used type “b” reduced scale plasma nozzle 120 according to FIGS. 6 and 11. Nozzle 120 had the outside diameter D2 of 22.80 mm, while commercially available nozzle 12 (HPR 130-260®, by Ajan®) had the outside diameter of 32.80 mm. Nozzle 120 was made of Cu—OF CW008/EN 13601 and at the load of 260 A its average lifespan was 36% longer than that of commercial nozzle 12, made of CuTeP CW118C.

[0131] Adapter 200 employed in this experiment was of type “b” according to FIG. 9b. After nozzle 120 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 120 with a brand new nozzle 120. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 120 were consumed. Nozzle 120 withstood the concentrated load of 82.8 A per mm.sup.2 of the cross-section of aperture 101. Upon comparing the manufacturing cost of 20 pcs of nozzles 12 for the load of 260 A against the manufacturing cost of 20 pcs of reduced scale nozzles 120 of type “b” for the load of 260 A plus 1 pc of type “b” adapter 200, it was established that for the solution according to the submitted invention, the material consumption was reduced by 67% and the manufacturing time was reduced by 45%.

Comparative Experiment 3

[0132] To test reduced scale nozzles 100 for the load of 260 A, we used type “c” reduced scale plasma nozzle 100 according to FIGS. 7c and 12. Nozzle 100 had the largest outside diameter D2 of 16.70 mm, while commercially available nozzle 13 (HPR 400 XD®, by HYPERTHERM®) had the outside diameter of 26.85 mm. Nozzle 100 was made of Cu—OF CW008A/EN 13601 and at the load of 260 A its average lifespan was 38% longer than that of commercial nozzle 13, made of CuTeP CW118C.

[0133] Adapter 200 employed in this experiment was of type “e” according to FIG. 9e. After nozzle 100 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 100 with a brand new nozzle 100. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 100 were consumed. Nozzle 100 withstood the concentrated load of 82.8 A per mm.sup.2 of the cross-section of aperture 101. Upon comparing the manufacturing cost of 20 pcs of nozzles 13 for the load of 260 A against the manufacturing cost of 20 pcs of reduced scale nozzles 100 of type “c” for the load of 260 A plus 1 pc of type “e” adapter 200, it was established that for the solution according to the submitted invention, the material consumption was reduced by 72.8% and the manufacturing time was reduced by 20.5%.

Comparative Experiment 4

[0134] To test reduced scale nozzles 100 for the load of 130 A, we used type “d” reduced scale plasma nozzle 100 according to FIGS. 7d and 13. Nozzle 100 had the largest outside diameter D2 of 14.10 mm, while commercially available nozzle 14 (HPR 130®, by Hypertherm®) had the outside diameter of 28.45 mm. Nozzle 100 was made of Cu—OF CW008A/EN 13601 and at the load of 130 A its average lifespan was 52% longer than that of commercial nozzle 14, made of CuTeP CW118C. After applying a chromium layer 0.008 to 0.012 mm thick using galvanic plating, the lifespan of nozzle 100 was extended by additional 62%.

[0135] Adapter 200 employed in this experiment was of type “d” according to FIGS. 9d and 13. After nozzle 100 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 100 with a brand new nozzle 100. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 100 were consumed. Nozzle 100 withstood the concentrated load of 84.5 A per mm.sup.2 of the cross-section of aperture 101. Upon comparing the manufacturing cost of 20 pcs of nozzles 14 for the load of 130 A against the manufacturing cost of 20 pcs of reduced scale nozzles 100 of type “d” for the load of 130 A plus 1 pc of type “d” adapter 200, it was established that for the solution according to the submitted invention, the material consumption was reduced by 85% and the manufacturing time was reduced by 54%.

Comparative Experiment 5

[0136] To test reduced scale nozzles 100 for the load of 130 A, we used type “d” reduced scale plasma nozzle 100 according to FIGS. 7d and 14. Nozzle 100 had the largest outside diameter D2 of 14.10 mm, while commercially available nozzle 15 (PerCut 450®, by Kjellberg®) had the outside diameter of 24.0 mm. Type “d” nozzle 100 was made of Cu—OF CW008A/EN 13601 and at the load of 130 A its average lifespan was 33% longer than that of commercial nozzle 15, made of CuTeP CW118C. After applying a nickel layer 0.008 to 0.012 mm thick using galvanic plating, the lifespan of nozzle 100 was extended by additional 52%.

[0137] Adapter 200 employed in this experiment was of type “f” according to FIGS. 9f and 14. After nozzle 100 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 100 with a brand new nozzle 100. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 100 were consumed. Nozzle 100 withstood the concentrated load of 84.5 A per mm.sup.2 of the cross-section of aperture 101. Upon comparing the manufacturing cost of 20 pcs of nozzles 15 for the load of 130 A against the manufacturing cost of 20 pcs of reduced scale nozzles 100 of type “d” for the load of 130 A plus 1 pc of type “f” adapter 200, it was established that for the solution according to the submitted invention, the material consumption was reduced by 75% and the manufacturing time was reduced by 29%.

Comparative Experiment 6

[0138] To test reduced scale nozzles 100 for the load of 30 A, we used type “e” reduced scale nozzle 100 according to FIGS. 7e and 15. Nozzle 100 of this type had the outside diameter D2 of 15.7 mm, while commercially available nozzle 16 (HPR 130®, by Hypertherm®), whose design matches U.S. Pat. No. 5,317,126, had the outside diameter of 28.45 mm. Nozzle 100 was made of Cu—OF CW008A/EN 13601 and at the load of 30.0 A its average lifespan was 12% longer than that of commercial nozzle 15, made of CuTeP CW118C.

[0139] Adapter 200 employed in this experiment was of type “a” according to FIGS. 9a and 15. Adapter 200 was used to test reduced scale nozzles for the load of 30 A. After nozzle 100 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 100 with a brand new nozzle 100. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 100 were consumed. Nozzle 100 withstood the concentrated load of 30 A per mm.sup.2 of the cross-section of aperture 121. Upon comparing the manufacturing cost of 20 pcs of nozzles 15 for the load of 30 A against the manufacturing cost of 20 pcs of reduced scale nozzles 100 of type “e” for the load of 30 A plus 1 pc of type “a” adapter 200, it was established that for the solution according to the invention, the material consumption was reduced by 78% and the manufacturing time was reduced by 51%.

Comparative Experiment 7

[0140] To test reduced scale nozzles 100 for the load of 130 A, we used type “f” reduced scale nozzle 100 according to FIGS. 7f and 16. Nozzle 100 according to the invention had the outside diameter D2 of 14.60 mm, while commercially available nozzle 17 (HPR 400 XD®, by Hypertherm®) had the largest outside diameter of 26.85 mm. Nozzle 100 was made of Cu—OF CW008A/EN 13601 and at the load of 130 A its average lifespan was the same as that of commercially available nozzle 17, made of CuTeP CW118C.

[0141] Adapter 200 employed in this experiment was of type “c” according to FIG. 9c. After nozzle 100 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 100 with a brand new reduced scale nozzle 100. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 100 were consumed. Nozzle 100 withstood the concentrated load of 82.0 A per mm.sup.2 of the cross-section of aperture 121. Upon comparing the manufacturing cost of 20 pcs of nozzles 17 for the load of 130 A against the manufacturing cost of 20 pcs of reduced scale nozzles 100 of type “f” for the load of 130 A plus 1 pc of type “c” adapter 200, it was established that for the solution according to the invention, the material consumption was reduced by 82.3% and the manufacturing time was reduced by 42.2%.

Comparative Experiment 8

[0142] To test reduced scale nozzles 120 for the load of 30 A, we used type “g” reduced scale nozzle 120 according to FIGS. 8g and 17. Nozzle 120 according to the invention had the largest outside diameter D2 of 22.8 mm, while commercially available nozzle 18 (HP 130-260 XD®, by AJAN®) had the outside diameter of 32.8 mm. Nozzle 120 was made of Cu—OF CW008A/EN 13601 and its average lifespan was 15% longer than that of commercially available nozzle 18, made of CuTeP CW118C.

[0143] Adapter 200 employed in this experiment was of type “b” according to FIGS. 9b and 17. After nozzle 120 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 120 with a brand new reduced scale nozzle. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 120 were consumed. Nozzle 120 withstood the concentrated load of 78.0 A per mm.sup.2 of the cross-section of aperture 121. Upon comparing the manufacturing cost of 20 pcs of nozzles 18 for the load of 30 A against the manufacturing cost of 20 pcs of reduced scale nozzles 120 of type “g” for the load of 30 A plus 1 pc of type “b” adapter 200, it was established that for the solution according to the invention, the material consumption was reduced by 69.5% and the manufacturing time was reduced by 44.0%.

Comparative Experiment 9

[0144] To test reduced scale nozzles 120 for the load of 130 A, we used type “h” reduced scale nozzle 120 according to FIGS. 8h and 18. Nozzle 120 according to the invention had the largest outside diameter D2 of 22.8 mm, while commercially available nozzle 19 (HP 130-260 XD®, by AJAN®) had the outside diameter of 32.8 mm. Nozzle 120 was made of Cu—OF CW008A/EN 13601 and its average lifespan was the same as that of commercially available nozzle 19, made of CuTeP CW118C. After applying a nickel layer 0.008 to 0.012 mm thick using galvanic plating, the lifespan of nozzle 120 was extended by additional 26%.

[0145] Adapter 200 employed in this experiment was of type “b” according to FIGS. 9b and 18. After nozzle 120 was worn out at point 111 of its most strained segment, it was necessary to replace the worn-out nozzle 120 with a brand new reduced scale nozzle. There was no wear on adapter 200. Adapter 200 continued to perform its function even after 20 pcs of nozzles 120 were consumed. Nozzle 120 withstood the concentrated load of 84.5 A per mm.sup.2 of the cross-section of aperture 121. Upon comparing the manufacturing cost of 20 pcs of nozzles 19 for the load of 130 A against the manufacturing cost of 20 pcs of reduced scale nozzles 120 of type “h” for the load of 130 A plus 1 pc of type “b” adapter 200, it was established that for the solution according to the invention, the material consumption was reduced by 69.5% and the manufacturing time was reduced by 45.4%.

REFERENCE SIGNS LIST

[0146] 100 reduced scale nozzle cooled directly by liquid coolant [0147] 101 divergent aperture [0148] 102 aperture designed to lead away some of plasma gas [0149] 103 liquid-cooled surface [0150] 104 narrowest point of aperture [0151] 105 conically shaped spot [0152] 106 radius shaped spot [0153] 108 elliptically shaped spot [0154] 109 seal between reduced scale nozzle and adapter [0155] 110 mounting surface for attaching reduced scale nozzle to plasma torch [0156] 111 most strained segment of nozzle [0157] 120 reduced scale nozzle cooled by liquid coolant indirectly [0158] 121 cylindrical aperture [0159] 123 cooling surface seat [0160] X convergent part of nozzle [0161] X divergent part of nozzle [0162] L1 combined length of convergent and divergent parts [0163] L2 distance between cooled surface 103 and narrowest point 104, or beginning of aperture 121 [0164] L3 distance between cooled surface 103 and end of aperture 101 or 121 [0165] D1 smallest diameter of aperture 101 or 121 [0166] D2 largest outside diameter of reduced scale nozzle [0167] D4 diameter at end of divergent aperture 101 [0168] D22 largest outside diameter of reduced scale nozzle after adapter is attached [0169] 200 adapter [0170] 201 place where adapter 200 touches plasma torch 300 [0171] 202 place where reduced scale nozzle 100 or 120 touches adapter [0172] 209 seal between adapter 200 and plasma torch 300 at location 201 [0173] 300 plasma torch [0174] V direction of plasma flow [0175] A° angle of cone at location 105