Plasma Arch Torch Cutting Component With Optimized Water Cooling

• US 20080210669A1
• Filed: 02/08/2008
• Published: 09/04/2008
• Est. Priority Date: 02/09/2007
• Status: Active Grant

• Current Assignee: Hypertherm Incorporated
• Original Assignee: Hypertherm Incorporated
• Inventors: Yang, Yong, Shipulski, E. Michael, Cook, David Jonathan
• Granted Patent: US 8,772,667 B2
• Time in Patent Office: Days
• US Class Current: 219/121.49
• CPC Class Codes: B23K 10/00 Welding or cutting by means of a plasma
• CPC Class Codes: H05H 1/28 Cooling arrangements
• CPC Class Codes: H05H 1/34 Details, e.g. electrodes, nozzles
• CPC Class Codes: H05H 1/3436 Hollow cathodes with internal coolant flow
• CPC Class Codes: H05H 1/3442 Cathodes with inserted tip
• CPC Class Codes: H05H 1/3457 Nozzle protection devices

Abstract

A nozzle or retaining cap for a plasma arc torch that includes a surface defining a conductive contact portion for exchanging heat with an adjacent torch component. The adjacent torch component can be a retaining cap, electrode or nozzle. The surface of the nozzle or retaining cap can also at least partially define a cooling channel having a curvilinear surface. A sealant portion can be positioned between the conductive contact portion and the cooling channel. The sealant portion can form or create a fluid barrier between the cooling channel and the conductive portion.

Claims

1. A nozzle for a plasma arc torch comprising:

an exterior surface defining a conductive contact portion for exchanging heat with an adjacent torch component;

a fluid flow path having a curvilinear surface; and

a sealant portion positioned between the conductive contact portion and the fluid flow path.

2. The nozzle of claim 1, wherein the nozzle includes an elastomeric seal disposed within the sealant portion.

3. The nozzle of claim 1 further comprising a face seal on a surface of a rear portion of the nozzle.

4. The nozzle of claim 1, wherein the fluid flow path forms at least a portion of a toroidal chamber.

5. The nozzle of claim 1, wherein the fluid flow path includes at least a portion of a fluid chamber that includes a convex curvilinear portion and a concave curvilinear portion, the convex curvilinear portion promoting fluid flow into the concave curvilinear portion.

6. The nozzle of claim 1, wherein the conductive contact portion defines a curved or angled contact surface.

7. The nozzle of claim 6, wherein the contact surface provides axial and radial alignment of the nozzle to the adjacent torch component.

8. The nozzle of claim 1, wherein the conductive contact portion includes a layer of a conductive metal or metal oxide disposed thereon.

9. A retaining cap for a plasma arc torch, the cap comprising:

an interior surface defining a conductive contact portion for exchanging heat with an adjacent torch component;

a fluid flow path having a curvilinear surface; and

a sealant groove positioned between the conductive contact portion and the fluid flow path.

10. A cooling and sealing structure for coupling and providing heat transfer between adjacent plasma torch components, the structure comprising:

a shoulder portion to provide a contact interface with an adjacent torch component;

a convective cooling channel including a convex curvilinear portion, a concave curvilinear portion, and a tangential connection portion disposed between the convex and the concave curvilinear portions; and

a sealing portion positioned between the shoulder portion and the convective cooling channel.

11. The structure of claim 10, wherein the shoulder portion provides radial and axial alignment between at least two of the adjacent torch components.

12. The structure of claim 10, wherein the shoulder portion includes a layer of conductive material along the solid-to-solid interface.

13. The structure of claim 10, wherein the convective cooling channel includes a bulbous portion.

14. The structure of claim 10, wherein the convective cooling channel comprises a toroidal shape.

15. The structure of claim 10, wherein the elastomeric seal is configured to deform to provide a fluid seal about an angled or curved surface between at least two adjacent torch components.

16. The structure of claim 10, wherein the conductive contact portion, the convective cooling channel, and the elastomeric seal are part of a single plasma torch component.

17. A convective cooling structure for a plasma arc torch disposed in at least one of a nozzle and a retaining cap of the plasma arc torch, the convective cooling structure comprising:

a concave curvilinear portion defining at least a portion of a channel;

a convex curvilinear portion for promoting fluid flow into the concave curvilinear portion; and

a tangential connection portion disposed between the convex and concave curvilinear portions.

18. The convective cooling structure of claim 17, wherein the cooling structure is at least partially disposed within the nozzle.

19. The convective cooling structure of claim 18, wherein the cooling structure is at least partially disposed within the retaining cap.

20. The convective cooling structure of claim 17, wherein the channel is disposed within the nozzle of the plasma arc torch.

21. The convective cooling structure of claim 20, wherein the channel intrudes into a wall thickness of the nozzle.

22. The convective cooling structure of claim 17, wherein the channel is configured to reduce fluid flow stagnation.

23. A nozzle for use in a fluid-cooled plasma torch, the nozzle comprising:

a body having an outer perimeter that partially defines a fluid channel, the body including an end face, the end face is perpendicular to a longitudinal axis of the component;

a groove extending at least partially through the end face;

an elastomeric seal disposed within the groove to provide a barrier between a plasma gas flow and the fluid channel.

24. The nozzle of claim 23, wherein the elastomeric sealing element comprises an o-ring.

25. The nozzle of claim 23 further comprising a forward portion and a rear portion, the forward portion including a front face defining an exit orifice, a shoulder portion sized to provide conductive heat transfer with an adjacent component, and an elastomeric seal disposed between the shoulder portion and the rear portion, wherein the elastomeric seal deforms to provide a fluid seal with the adjacent component.

26. A cooling and sealing structure for coupling and providing heat transfer between plasma torch components, the structure comprising:

means for conductive cooling between adjacent torch components;

means for providing convective cooling of a portion of the plasma torch without stagnation of the cooling fluid; and

a sealing means for providing a fluid seal.

27. The cooling and sealing structure of claim 26 wherein the adjacent torch components include a nozzle and a retaining cap.

28. The cooling and sealing structure of claim 26 wherein the means for conductive cooling, the means for providing convective cooling, and the sealing means are at least partially located on a single plasma torch component.

29. The cooling and sealing structure of claim 26 wherein the means for providing effective convective cooling is defined between adjacent torch components.

30. The cooling and sealing structure of claim 26, wherein the means for conductive cooling also provides at least one of radial or axial alignment between the adjacent torch components.

31. An alignment structure for positioning adjacent components in a plasma torch, the structure comprising:

a step element to provide axial alignment between two adjacent components;

a sealing element in cooperation with an angled or curved surface to provide radial alignment between the two adjacent components; and

a convective cooling channel with a curvilinear portion.

32. The alignment structure of claim 31, wherein the step element and sealing element are disposed relative to each other to form a single alignment element.

33. The alignment structure of claim 31, wherein at least one of the step element and the angled or curved surface element includes a layer of a thermally conductive material disposed thereon.

34. A fluid cooled plasma arc torch nozzle comprising:

a forward portion and a rear portion, the forward portion including a front face defining an exit orifice;

a conductive shoulder portion sized to axially align with an adjacent component;

a fluid-cooled portion disposed between the shoulder portion and the rear portion; and

a sealing member disposed between the liquid cooling portion and the conductive shoulder portion.

35. The nozzle of claim 34 wherein the fluid-cooled portion comprises a toroidal shape.

36. A plasma arc torch system comprising:

a power supply;

a torch body connected to the power supply;

an electrode disposed within the torch body;

a torch component with a surface defining a conductive contact portion for exchanging heat with an adjacent torch component and a convective cooling structure comprising a concave curvilinear portion that defines at least a portion of a cooling channel.

37. The plasma arc torch system of claim 36 further comprising a sealing component dimensioned and configured to provide a fluid seal between the conductive contact portion and the convective cooling structure.

38. The plasma arc torch system of claim 36 wherein the sealing component is located on at least one of the torch component or the adjacent torch component.

39. The plasma arc torch system of claim 36 further comprising a controller and gas console.

40. A plasma arc torch system comprising:

a power supply;

a torch body connected to the power supply;

an electrode disposed within the torch body;

a controller that controls the flow of gas to the electrode;

a first cooling means for conductive cooling between adjacent torch components;

a second cooling means for providing convective cooling of a portion of the plasma torch without stagnation of a cooling fluid flow; and

a sealing means disposed between the first cooling means and the second cooling means to provide a fluid seal.

41. A method of cooling a plasma torch component comprising:

exchanging heat from a first torch component with an adjacent torch component through a conductive contact portion;

flowing a cooling fluid through a cooling channel having a curvilinear surface, the curvilinear surface configured to prevent fluid stagnation; and

providing a barrier comprising a sealing component between the conductive contact portion and the cooling channel.

42. A method of manufacturing a plasma torch component comprising:

forming a surface on a first torch component that defines a conductive contact portion for exchanging heat with an adjacent torch component;

creating a shaped portion of a cooling channel defined at least in part by one of the first torch component or the adjacent torch component, the shaped portion having a curvilinear surface; and

positioning a sealant groove between the surface and the shaped portion.

43. The method of claim 42 wherein the sealing component comprises at least one of an o-ring or elastomeric seal.

44. A nozzle for a plasma arc cutting torch having a substantially hollow body capable of receiving an electrode, the nozzle comprising:

an exterior surface that includes a portion having a curvilinear profile that at least partially defines a flow path for a cooling fluid.

45. A retaining cap for a plasma arc cutting torch configured to secure a nozzle within the torch, the retaining cap comprising:

an interior surface that includes a portion having a curvilinear profile that at least partially defines a flow path for a cooling fluid.