A life-extending electrode for use in a liquid-cooled plasma arc cutting torch, having an increased cooling surface by scraping from top to bottom, by pressing on the base surface, by forming parallel and / or at the same angle extending indentations and protuberances (also called concaves / convexities) on the inner surface cleaned by the coolant, as well as by increasing the instantaneous heat transfer rate by approaching a heat transfer barrier.

Abstract

The present invention relates to an extended life electrode for use in a liquid cooled plasma arc cutting torch having an increased cooling surface by scraping (also called scraping) from top to bottom, by pressing at the base surface, and by forming indentations and ridges extending parallel and / or at the same angle on an inner surface washed by a cooling liquid. [Reference figure] Figure 1

Description

[Technical field]

[0001] The present invention relates to liquid-cooled plasma cutting torches, in which innovative improvements made on the electrode allow for an increased surface area on the inner surface of the electrode, resulting in an increased life span and increased efficiency. Summary of the Invention [Problem to be solved by the invention]

[0002] For automatic or manual liquid cooling systems plasma cutting torches based on a similar architecture, electrodes known on the market include electrodes made of copper or silver and / or copper / silver and copper / silver alloys, an emitter insert inside an arc plasma cutting torch equipped with such an electrode, a gas diffuser and a body in which a nozzle for narrowing the plasma jet is fixed.

[0003] Typically, the electrodes used in these plasma torches consist of copper and / or silver and / or copper / silver and / or copper / silver alloys, either as an electron emitter cutter tip or as an electron emitter cutter tip secured thereto.

[0004] The cutter tip is tungsten or hafnium or zirconium. This insert (emitter cutter tip) is typically cylindrical in shape and is secured by stamping and crimping into a cavity such as a blind hole (the cavity in which the emitter cutter tip is secured) located at the downstream end of the electrode body.

[0005] It is well known that during the plasma cutting process, the emitter cutter tip (insert) is particularly exposed to very high temperatures and to suction forces generated to a greater or lesser extent by the arc plasma jet, which suction forces start to take root on the emitter cutter tip.

[0006] The metal or metal alloy forming the insert (emitter cutter tip) evaporates significantly, so that craters inevitably form inside said insert (emitter cutter tip), which have parts that do not solidify fast enough during the phase transition and thus are thrown into the plasma jet.

[0007] Due to this wear, this more or less rapid deterioration at the tip of the electrode of the plasma torch is almost inevitable and represents a real problem on an industrial scale.

[0008] It also affects the efficiency of the cutting process as it requires frequent replacement of the torch electrode, thus shutting down the system, stopping the cutting process and incurring additional costs.

[0009] If the emitter insert fails, it is not possible to replace just the insert; it is the entire electrode that must be replaced. [Means for solving the problem]

[0010] The present invention has been made to minimize the above mentioned drawbacks and to find a solution to this problem.

[0011] For this purpose, the coolant flow passage is formed on the side of the cylinder from the top surface of the upstream cylinder tip at the level of the blind hole to the level of the base surface of the inner blind hole, with scraped open indentations (also called dents) / bulges (also called protrusions) that are parallel to each other and equally spaced from top to bottom in the direction of the coolant flow, and The coolant flow passages are formed with pressed open indentations / ridges at equal spacing and angular extensions on the base surface of the medial blind hole so that the indentations / ridges of these passages correspond to each other.

[0012] The coolant flow passages are formed in the form of indentations and ridges by scraping from top to bottom on the outer surface of the inner single blind hole at equal intervals with the base surface of the inner single blind hole.

[0013] Thanks to the increased surface area obtained by the water channels opening on these three surfaces, the emitter cutter tip, which is exposed to high heat and needs to be cooled, is guaranteed from the most extreme point where the cutting process begins and the cooling of the nearest contact surface of the body is enhanced; thanks to the heat transfer barrier approach, the electrode life is extended for liquid-cooled plasma cutting torches. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a cross-sectional perspective view of a life-extending electrode for use in a liquid-cooled plasma arc cutting torch with an increased cooling surface by top-to-bottom scraping of the coolant-washed inner surface, by pressing the bottom surface, and by forming parallel and / or co-angular extending indentations and ridges. [Figure 2a] FIG. 2a is a cross-sectional view of a downstream tip electrode carrying a liquid coolant flow channel emitter cutter tip for a plasma cutting torch having a flat inner blind hole bottom surface. [Figure 2b] FIG. 2b is a cross-sectional view of a downstream tip electrode carrying a liquid flow channel emitter cutter tip for a plasma cutting torch having a sloped inner blind hole bottom. [Diagram 3] FIG. 3 is a cross-sectional view of a downstream electrode carrying a flat channel emitter cutter tip. [Figure 4] FIG. 4 is a cross-sectional view of the downstream electrode carrying the spring channel emitter cutter tip. [Explanation of symbols]

[0015] 1: An electrode with a liquid cooling system in a plasma arc torch that cuts metal pieces 2: The main body constituting the plasma electrode; 2a: downstream tip carrying the emitter cutter tip 2b: Upstream cylindrical tip at the level of the medial unicular blind hole 3: Emitter cutter tip, 4: A cavity in which the emitter cutter tip is secured; 5: Inner single eye blind hole, 5a: cylindrical outer surface of the medial blind hole; 5b: Base surface of the medial occipital cul-de-sac, 5c: outer diameter surface of upstream cylindrical tip at the level of the inner single blind hole; 6: Male and female thread passes that connect the electrode to the plasma torch 7: Coolant channel (also called coolant flow path) 8: Coolant immersion tube DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The present invention is a life-extending electrode for use in liquid-cooled plasma arc cutting torches with increased cooling surface, by scraping from top to bottom of the inner surface washed by the coolant, by pressing the bottom, and by creating indentations and ridges that extend parallel and / or with the same angle of extension and with the instantaneous heat transfer rate with the approach of the heat transfer wall; on the inner surface of the downstream tip (2a) carrying the emitter cutter tip, e.g. on the cylindrical outer surface (5a) of the inner ocular blind hole; on the outer surface of the upstream cylindrical tip (2b) at the level of the inner monocular blind hole, for example, on the outer diameter surface (5c) of the upstream cylindrical tip at the level of the inner monocular blind hole; and On the base surface of the medial unicular blind hole (5b), The openings are parallel to the flow direction of the cooling liquid, and are cut parallel to the side surfaces from top to bottom with the same number and angle, with equal spacing and extension. And, In a plasma torch for cutting metal pieces, the electrodes are provided with liquid-cooled electrodes (2) which form the plasma electrodes, and are pressed (squeezed) at equal intervals on the entire surface of the body (2) at the bottom portion, with the same angular extension. It has coolant channels (7) obtained with an increased surface area in the form of indentations / ridges (FIG. 1, FIG. 2a, FIG. 2b).

[0017] As can be seen in Figures 2a and 2b, the coolant flow channels (7) are obtained by forming indentations and ridges that are parallel to the coolant flow direction and of equal size and angle to each other and adjacent to each other by pressing (squeezing) on ​​the base surface (5b) of the inner monocular hole in the electrode with the liquid cooling system (Figure 1).

[0018] As can be seen in Figures 2a and 2b, the coolant flow paths (7) are obtained by forming indentations and ridges that are parallel to the coolant flow direction and of equal size and angle to each other, and adjacent to each other, by scraping from top to bottom on the outer diameter surface (5c) of the upstream cylindrical tip at the level of the inner single blind hole, extending to the level of the base surface (5b) of the inner single blind hole (Figure 1).

[0019] As can be seen in Figures 2a and 2b, the coolant flow channels (7) are obtained by forming indentations and ridges, adjacent to each other, parallel to the coolant flow direction and of equal size and angle, and by scraping from top to bottom on the cylindrical outer surface (5a) of the inner single blind hole (Figure 1).

[0020] Thanks to the increased surface area obtained by the open coolant channels (7) on these three surfaces (5a, 5b, 5c), the cooling of the closest contact surface (5a, 5b, 5c) with the cavity (4), where the emitter cutter tip (3) is exposed to high heat and needs to be cooled with coolant emanating from the coolant immersion tube (8) inside the inner single-eye blind hole (5), is further increased with the increased surface area, as a result of which the life of the electrode for liquid-cooled plasma arc cutting torches is extended and its more efficient use is ensured (Figures 1, 2a, 2b).

[0021] The flow direction of the coolant, coming from a coolant immersion tube (8) extending downwards from the middle of an inner single eye hole (5) in the body (2) of the electrode forming the plasma electrode, is indicated by arrows as seen in Figures 2a and 2b, and allows cooling of the emitter cutter tip (3) (tungsten, hafnium, zirconium, etc.), which is exposed to the suction force generated by the arc plasma jet during the operation of the electrode and performs the metal cutting process.

[0022] The coolant channels (7), formed by scraping or pressing on said surfaces (5a, 5b, 5c) with indentations and ridges, equidistant, parallel or at equal angles to one another, may be made of indentations and ridges of any kind of geometric cross-section, as well as any kind of geometrical extension that can ensure the highest surface increase.

[0023] A cross section of a downstream electrode carrying an emitter cutter tip (3), designed as a straight channel, is shown in Figure 3. Furthermore, as an example, a cross section of a downstream electrode carrying an emitter cutter tip (3), designed as a spring channel, is shown in Figure 4.

[0024] In the case of the plasma cutting torch shown in FIG. 2a, the base surface (5b) of the inner single blind hole of the downstream tip electrode carrying the emitter cutter tip with the liquid cooling system for the plasma cutting torch can be flat as shown in FIG. 2a, or angled as shown in FIG. 2b, or can include any kind of geometric cross section and shape to obtain the highest surface augmentation.

[0025] The diameter of the upstream cylindrical tip at the level of the single blind hole can be adjusted proportionally to the depth of the passage to be opened according to the diameter of the emitter cutter tip (3) calculated according to the cutting amperage.

[0026] With dives of suitable depth, operations can be carried out on steel pins of suitable quality which should be prepared to allow surface increase for operations such as in-hole, hole-bottom and outer cylinder by means of contour chip removal (chip removal with a tool in the form of a contour knife, shaping by squeezing), by dismantling and cutting, cleaning and removing the chips, scraping and cutting off.

[0027] The knives can be produced using CNC controlled multi-axis machining benches with high axis positioning and repeatability and capable of multi-operation, wire cutting erosion benches capable of cutting at 0.02-0.03 line, CNC sinking erosion, CNC turret lathes, CNC precision grinding.

[0028] Using a surface polishing system it is possible to minimize the surface roughness of these knives, which can perform thousands of operations without deterioration, since the operating metals are copper or silver and / or copper-silver and / or alloys.

[0029] The electrode life is 2905 blasted from 25 mm thick, A1 quality soft iron sheet cutting, made with a 260 amp electrode, with these coolant channels (7) formed with increased surface area, which is given an extended life of about 60% thanks to the coolant channels (7) opening on the outer surface of the upstream cylindrical tip (2b) at the level of the inner monocular hole, and about 40% thanks to the coolant channels (7) opening on the base surface (5b) of the inner monocular hole.

[0030] For cuts made using the same system catalog cutoff parameters of the same amperage, thickness, and geometry, an increase of approximately 2x was achieved compared to electrodes with a non-enhanced cooling surface.

[0031] The increase in the cylindrical outer surface (5a) of the medial monocular blind hole, not included in the test, can be formed by indentations and protuberances made in suitable geometric shapes, the increase in surface area on the three surfaces (5a, 5b, 5c) being approximately double.

[0032] This allows one electrode to perform the functions of two or more electrodes.

[0033] The interruption of the cutting system in electrode replacement, electrode manufacturing costs, time, energy loss, excessive raw material consumption, and many other negative drawbacks resulting therefrom are reduced.

[0034] In addition, if necessary, a two-fold increase in surface area can be achieved by means of an indentation and a protuberance formed on the upper surface of the upstream cylindrical tip (2b) at the level of the medial unicular blind hole.

Claims

1. A life-extending electrode for use in a liquid-cooled plasma arc cutting torch with coolant flow passages (7) obtained with an increased cooling surface by scraping (also called scraping or scraping off) the inner surface washed with coolant from the top to the bottom, by pressing (also called pressing) at the bottom, and by forming indentations (also called depressions) and protrusions (also called protrusions) running parallel and / or at the same angle, which is on the inner surface of the downstream end carrying the emitter cutter tip, i.e. on the cylindrical outer surface (5a) of the inner blind hole; on the outer surface of the upstream cylindrical tip at the level of the inner monocular blind hole, in other words, on the outer diameter surface (5c) of the upstream cylindrical tip at the level of the inner monocular blind hole; and On the base surface of the medial occipital foramen (5b), The openings are cut parallel to the coolant flow direction, from top to bottom, with the same number and angle on the side, and are equally spaced and at equal angles; and In a plasma torch for cutting metal pieces, an electrode having a liquid cooling system is formed with openings at the bottom portion at equal intervals and at the same angle on the entire surface of the body (2) forming the plasma electrode, the openings being pressed or squeezed.

2. A life-extending electrode for use in a liquid-cooled plasma arc cutting torch, with coolant flow channels (7), obtained with an increase in the cooling surface by scraping (also called chipping or scraping) from top to bottom (also called bottom) on the inner surface cleaned by the coolant, by pressing at the bottom and by forming indentations and ridges extending parallel and / or at the same angle, according to claim 1, It is a life-extending electrode characterized in that it has coolant flow passages (7) which are arranged parallel to the coolant flow direction, equally spaced and at equal angles to each other, and which have an increased surface area formed by indentations and protuberances made of scrap, adjacent to each other, from top to bottom on the cylindrical outer surface (5a) of the inner single-eye blind hole.

3. A life-extending electrode for use in a liquid-cooled plasma arc cutting torch, with coolant flow channels (7), obtained with an increase in the cooling surface by scraping (also called chipping or scraping) from top to bottom (also called bottom) on the inner surface cleaned by the coolant, by pressing at the bottom and by forming indentations and ridges extending parallel and / or at the same angle, according to claim 1, It is a life-extending electrode, characterized in that it has coolant flow paths (7) which are equidistant from each other in the direction of coolant flow and adjacent to each other with the same angular extension, and which have a surface increase in the form of indentations and ridges, by pressing or squeezing against the base surface (5b) of an inner monocular blind hole in the electrode with a liquid cooling system.

4. A life-extending electrode for use in a liquid-cooled plasma arc cutting torch, with coolant flow channels (7), obtained with an increase in the cooling surface by scraping (also called chipping or scraping) from top to bottom (also called bottom) on the inner surface cleaned by the coolant, by pressing at the bottom and by forming indentations and ridges extending parallel and / or at the same angle, according to claim 1, It is a life-extending electrode characterized in that it has coolant flow paths (7) adjacent to each other, equally spaced, of equal size and at equal angles, parallel to the direction of coolant flow, and which have a surface increase in the form of indentations and ridges, obtained by scraping from top to bottom (also called the bottom) on the outer diameter surface (5c) of the upstream cylindrical tip, which is at the level of the inner single-eye hole, and extending down to the level of the base surface (5b) of the inner single-eye hole.

5. A life-extending electrode for use in a liquid-cooled plasma arc cutting torch, with coolant flow channels (7), obtained with an increase in the cooling surface by scraping (also called chipping or scraping) from top to bottom (also called bottom) on the inner surface cleaned by the coolant, by pressing at the bottom and by forming indentations and ridges extending parallel and / or at the same angle, according to claim 1, A life-extending electrode (1) characterized in that, for more cooling of the emitter cutter tip (3) exposed to high heat during use, a coolant flow passage (7) having equally spaced indentations and protuberances is opened on the closest contact surface (5a, 5b, 5c) with the cavity (4) in which the emitter cutter tip is fixed, and by enabling the passage of coolant emitted to the liquid immersion tube (8) from the surface of the coolant flow passage (7), the life-extending electrode (1) has an extended life and service life due to more cooling of the emitter cutter tip (3).

6. A life-extending electrode for use in a liquid-cooled plasma arc cutting torch, with coolant flow channels (7), obtained with an increase in the cooling surface by scraping (also called chipping or scraping) from top to bottom (also called bottom) on the inner surface cleaned by the coolant, by pressing at the bottom and by forming indentations and ridges extending parallel and / or at the same angle, according to claim 1, A life-extending electrode, characterized in that it has coolant flow channels (7) obtained with surface increases formed by indentations and ridges, which are parallel to one another, equidistant and at equal angles, on said surfaces (5a, 5b, 5c), in all kinds of geometrical sections and in all kinds of geometrical extensions allowing the highest surface increases.

7. A life-extending electrode for use in a liquid-cooled plasma arc cutting torch, with coolant flow channels (7), obtained with an increase in the cooling surface by scraping (also called chipping or scraping) from top to bottom (also called bottom) on the inner surface cleaned by the coolant, by pressing at the bottom and by forming indentations and ridges extending parallel and / or at the same angle, according to claim 1, A life-extending electrode, characterized in that the base surface (5b) of the inner single-eye blind hole of the downstream tip electrode carrying an emitter cutter tip with a coolant system for a plasma cutting torch has a base surface (5b) that can be flat, angled, or of all kinds of geometrical pieces and shapes that allow the highest surface increase.

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