WO1980002245A1

WO1980002245A1 - A flux cored welding electrode and method of making and using

Info

Publication number: WO1980002245A1
Application number: PCT/US1980/000485
Authority: WO
Inventors: R Eytchison
Original assignee: R Eytchison
Priority date: 1979-04-23
Filing date: 1980-04-21
Publication date: 1980-10-30
Also published as: EP0027467A1; GB2059845A

Abstract

The object of the invention is to provide a flux filled welding electrode. Said electrode is formed in the shape of a square (100) with the flat sides (102) connected by rounded comers (104). With this shape there is a smoother surface which causes less wear to a wire feeder (60) cable and gun assembly (84). A square electrode (100) can be fed through a die (104) to reduce size and form a circular electrode (24). The method of forming the electrode is, form metal in tube shape (18) with flux and form to fill shape desired.

Description

AFLUX CORED WELDING ELECTRODE AND METHOD OF MAKING AND USING

BRIEF DESCRIPTION OF THE INVENTION

This invention is directed to the making and using of a tubular welding electrode. In a lateral cross-sectional view the electrode may have a, generally, square configuration. Also, the square configuration may be processed to a circular configuration electrode.

The electrode is made from a coil of strip metal which is formed into a channel. Then, there is introduced into the channel a welding flux such as a filler alloy and slagging element. The channel is closed and the channel is formed into the tubular welding electrode of the, generally, square configuration. The tubular welding electrode is continuous and can be wound on a spool or formed into a coil reeled or placed in a pack. At the site of usage, the electrode is straightened and fed into the wire feeder, cable and gun assembly for welding.

The tubular welding electrode of the square configuration is a lateral cross-sectional view, has four sides, or four flat surfaces and four round corners. The feed rolls contact the four sides or the four flat surfaces of this tubular welding electrode and cause some scuffing and serrating of these flat surfaces to produce indentations in these four sides. The corners are not serrated and are not scuffed, but are substantially smooth. In the contact tips of the cable and gun assembly, the smooth round corners are in contact with the contact tips. Therefore, the contact tips and guide springs are not subjected to a filing action and are not scarred and marred and unduly worn. These smooth surfaces of the corners produce little wear on these areas. Further, there is not the back pressure of the feed rolls as the corners are smooth. The result is that the drive system for feeding the tubular welding electrode to the cable and gun assembly and the contact tips in the cable and gun assembly are not unduly worn and have a longer-working life than the corresponding components have with a tubular welding electrode having a round or circular configuration in a lateral cross-sectional view.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1 is a schematic illustration of the process for making a welding rod filled with the flux and illustrates the process for making a welding rod, in a lateral cross-sectional configuration, of a round design and also, illustrates the making, in a lateral cross-sectional configuration, of a, generally, square electrode having four sides joined by curved corners;

FIGURE 2 illustrates a first set of feed rolls for feeding the square tubular welding electrode to the welding gun;

FIGURE 3 illustrates a second set of feed rolls for feeding the tubular welding electrode to the welding gun;

FIGURE 4 illustrates a third set of feed rolls for feeding the tubular welding electrode to the welding gun;

FIGURE 5 is a fragmentary view, illustrating the feed rolls in contact with a round tubular welding rod and the feed rolls forming indentations on the surface of the round tubular welding electrode;

FIGURE 6 is a fragmentary view, illustrating the feed rolls in contact with the sides of the square of the square tubular welding electrode to form indentations on said sides and also illustrates the round corners of the welding electrode not in contact with the feed rolls;

FIGURE 7 is an isometric view illustrating the metal tube, the guide spring and the round tubular welding electrode inside of said guide spring and said metal tube of the welding gun;

FIGURE 8 is an isometric view, illustrating the metal tube, the guide spring and the square tubular welding electrode inside of said guide spring and said metal tube of the welding gun;

FIGURE 9 is a fragmentary longitudinal cross-sectional view of a metal tube, guide spring and round tubular welding electrode inside the guide spring in the metal tube of the welding gun;

FIGURE 10 is a fragmentary longitudinal cross-sectional view of a metal tube, guide spring and the tubular welding electrode inside said guide spring in the metal tube of the welding gun;

FIGURE 11 is a schematic illustration of a water-cooled welding gun; and,

FIGURE 12 is a schematic illustration of a die and the step for making a round tubular electrode, of smaller dimension, from a square tubular electrode.

THE SPECIFIC DESCRIPTION OF THE INVENTION

In welding and, especially, in continuous welding, there is used a tubular welding electrode filled with a flux. The conventional electrode, in a cross-sectional configuration is round or circular.

The electrode is made of a thin wall material. For example, a roll of flat metal is formed into a channel. Then there is introduced into the channel a flux, such as a filler alloy and slagging elements. Then, this filled channel is further processed and formed into a sealed or closed tube of a round configuration. The closed tube may have a diameter of 0.160 inches. The diameter of this welding electrode is reduced by a number of steps, say ninteen steps, to a diameter of 0.094 inches. Then, the 0.094 inch diameter filled electrode may be drawn, in four steps, or rolled in twenty steps, to a diameter of 0.0625 inches (1/16th inch). It is my understanding that over ninety (90%) per cent of the filled welding electrode is drawn to a diameter of say 0.0625 inches and not rolled to that diameter. The reader is to understand that the diameter of the welding electrode may be different from the above specified diameters. The difference will depend upon the use to which the welding electrode is placed and also upon the preference of the manufacturer and the preference of the user.

After the filled electrode has been formed to the desired diameter, the filled electrode is wound on a spool or wound in a coil or placed packs for shipping to the customer. The reader is to realize that the filled electrode on the spool or in the coils or in the packs has a camber and, also, has a helical twist to it. At the site of usage, the filled electrode is fed through a straightener so as to take out the camber and to take out the helical twist. If the camber and helical twist are not removed, then it is more difficult to feed and introduce the tubular welding electrode to the wire feeder, cable and gun assembly for welding. In the wire feeder, for the cable and gun assembly, there are feed rolls. The feed rolls are generally of a "V" configuration and have a point contact with the round welding electrode. The feed foils in contacting the outer surface of the round welding electrode bite into this outer surface and scar the outer surface so as to produce indentations or serrations on the outer surface of the welding electrode. The welding electrode, upon being forced into the guide tube and cable gun assembly, rub against the cable and gun assembly and, also rub against the contact tip of the welding gun. The indentations or serrations on contacting the cable and gun assembly and the contact tip in the welding gun function as a file and, unduly, wear the cable and gun assembly and the contact tip. In addition to the wearing of the cable and gun assembly and the contact tip, there is a back pressure on the wire drive which in itself produces more wear on the wire drive system. In essence, the indentations or serrations on the outer surface of the round tubular welding electrode having a round cross-sectional configuration cause undue wear on the welding equipment.

In order to lessen the formation of indentations on the outer surface of the round tubular welding electrode, and especcally in the large round diameter tubular welding electrode, there may be used spur gears for feeding the tubular welding electrode to the cable and gun assembly. The spur gears have a groove cut into them and act as a wire guide for feeding the tubular welding electrode to the cable and gun assembly. The spur gears and the groove tend to indent the outer surface of the welding electrode. The indentation of the outer surface of the welding electrode is less harmful and cau less wear on the contact tips and the cable and gun assembly than a tubular electrode having serrations. Again, the spur gears with a guide are used on the larger diameter welding electrodes and not on the smaller diameter welding electrodes. With the smaller cross-sectional area tubular welding electrodes, either a circular configuration or a square configuration, there are used feed rolls and not spur gears. THE DETAILED DESCRIPTION OF THE INVENTION

In FIGURE 1 there is illustrated the manner in which a piece of strip metal is formed into round tubular and filled welding rod. There is a piece of strip metal 10. This strip metal 10 may be on a roll of an indefinite length. It is to be realized that the width and the thickness of 10 may vary, but one width is 0.505 inches, and the thickness may be from 0.010 inches to 0.030 inches. Then, the edges of 10 are bent upwardly to form a U channel 12 having a base 14 and two upwardly directed legs 16. The transformation of the strip 10 to the U-channel 12 may be on a roll forming mill. Then, with further roll forming mill operations the U-channel 12 may be converted into a circular channel 18 having an opening 20.

A funnel or feeding device 22 may be inserted into the interior of the circular channel 18, through the opening 20, and there may be introduced into the circular channel 18 a welding flux 24, such as a filler alloy and slagging element.

Then, by a roll forming, process there may be formed a U-channel 26 having a lap joint 28. It is seen that in the U-channel 26 there is the welding flux 24. Or, by a roll forming process there may be formed a Uchannel 30 with a butt joint 32 and a filler 24.

The channels 26 and 30 have a diameter of approximately 0.160 inches. Then, the channels 26 and 30 may be rolled between circular rollers 34 having a circular inset 36 to form a circular welding rod 38 having a filler 24. The diameter of the circular welding rod 38 is 0.094 inches diameter. To go from the channel 26 or the channel 30 to the circular welding rod 38 requires, approximately, nineteen steps or nineteen rolling operations or paths between nineteen sets of rolls to reduce the diameter. Then, the circular welding rod 38 can be reduced in diameter to a circular welding rod 40 having a diameter of approximately 0.0625 inches or 4/64 inches. The circular welding rod 38 can be reduced to 40 by means of drawing the welding rod 38 in a series of steps or through a series of dies to form the welding rod 40. Or, the welding rod 38 may be rolled in twenty steps or may pass between twenty sets of rollers to form the welding rod 40. It is to be remembered that the welding rod 40 is filled with welding flux 24. Then, the circular welding rod 40 can be formed into a coil 42 having a weight of 60 pounds. Or, the circular wire 40 may be placed into a drum 44 having a weight as much as 1000 pounds. If it is assumed that the circular wire 40 has a weight of 8 to 10 grams per foot, it is seen that the minimum length of the wire in the coil 42 is about 2700 feet and the minimum length of the wire in the drum 44 is about 8.5 miles.

The circular filled welding rod 40 may be shipped in coil form, reeled form or drum form to the place of usage. At the place of usage the circular wire 40 must be straightened so as to be able to be fed to the welding gun without sprialing and coiling. In FIG. 1 there is illustrated a set of three rolls 46. The wire 40 is passed between these three foils 46 to straighten the wire. The rolls 46 may be a V-roll having inwardly recessed surfaces 50 in the form of a V-roll or the rolls 46 may be a roll 52 having an inwardly recessed surface 54.

With the wire 40 it is to be noted that informing the coil 42 or forming the coil in the drum 44 there is a camber imparted to the wire and also in helical configuration. In the straightening of this wire 40 by means of straightening rolls 46 and the straightener 41, it is desirable to remove the camber and the helical configuration. The reason for removing the camber and the helical configuration is that if the wire is in a helical configuration and has camber there is a hunting action of the electrode for making the arc move when welding. In other words, the electrode which controls the action of the gun in the welding process is continually trying to follow the action of the circular wire as it goes through the gun and contacts the surfaces to be welded together. If the circular wire is not completely straight but has a camber and also a helical twist or coil to it, then the wire 40 is continually moving and the electrode is continually moving so that there is a hunting action and it is more difficult to achieve a desired welding bead on the metal being welded.

After the wire 40 has been straightened by being drawn through the straightening rolls 46 the wire goes to drive rolls 60. On the shaft 62 there are two drive rolls 60. Then, there is a second shaft 64 with two drive rolls 60. The shafts 62 and 64 pass through the passageway 6y in the drive rolls.

The drive rolls 60 are V-shaped drive rolls, and it is seen that the 40 passes between the inner surfaces of the four co-acting drive rolls 60.

It is seen that the drive rolls 60 have a hub portion 68 and two sloping sides 70. On the sloping sides 70 it is seen that there are radial grooves 72. The radial grooves 72 are cut into the surfaces 70. The radial grooves leave sharp edges on the surfaces 70. When the wire 40 passes through the four drive rolls 60, the wire is squeezed and pressed to a degree so that there are four sets of lateral indentations or grooves 74 on the surface of the wire 40.

The grooves 74 in the surface of the wire 40 can be compared to a file. In other words, the surface of the wire 40 is a file with four filing surfaces as there are four sets of grooves.

In FIGURE 11 there is illustrated a welding gun 80. The illustration of the welding gun 80 shows a longitudinal cross-sectional view.

in the gun 80 it is seen that there is a metal tube 82. In the metal tube 82 there is positioned a spring 84. Around the metal tube 82 there is an insulating tube 86. The insulating tube 86 may be of a suitable plastic such as polyethylene. Then, there is wrapped around the insulating tube 86 a braided copper wire conductor 88. On the outside of the copper wire conductor 88 there is insulating 89. Then, around the insulation 89 and the braided cooper wire conductor 88 there is a water jacket 90.

The braided cooper wire conductor 88 may carry 500 to 600 amps. The heat generated from this amperage can be considerable. Therefore, it is necessary to cool the conductor 88. A satisfactory way of cooling the conductor 88 is by means of the water jacket 90.

There connects to the end of the metal tube 82 a metal contact tip 92. The braided cooper wire conductor 88 also connects with the metal contact tip 92.

The wire 40 is positioned inside of the spring 84 in the metal tube 82 and passes through the metal tube 82 by passing through the spring 84. Then, the wire 40 passes through the metal contact tip 92.

Further, there is a handle 94 which connects with the gun 80. In the handle 94 there is a trigger 96. When the trigger 96 is activated, it starts the wire drive comprising the sets of spools or rolls 60 to feed the wire 40 through the spring 84 and the gun 80. It is to be understood that the welding gun is old and commercially available. There are welding guns which are water cooled and also which are gas cooled by carbon dioxide or argon and ambient air.

Now, with the surface of the wire 40 having four sets of grooves or indentations 74 and, in effect, being a file, it is seen that the wire 40 is passing through the gun 80 cuts and abrades the spring 84 and also cuts and abrades the metal contact 92 so as to wear these components at a faster than normal wear rate. To repeat, the grooves or indentations 74 on the wire 40 make the wire 40 similar to a file having four filing surfaces. These four filing surfaces, abnormally, wear the spring 84 and the metal contact tip 92.

Further, the abrading action of the grooves 74 in the wire 40 cause a back pressure which makes it more difficult to push or drive the wire 40 through the spring 84 and out of the metal contact tip 92.

By way of background, it is to be realized that the metal contact tip 92 is about 1/2 inch or an inch away from the material being welded. The amount of wire 40 which is subjected to the amperage of 500 or 600 amps is about 1/2 or 1 inch. The wire 40 is driven through the gun 80 at a speed up to 200 inches per minute. At the rate of 200 inches per minute and with four sets of indentations or grooves 74 on the surface of the wire 40 it can be realized that the spring 84 and the metal contact tip 92 can soon be abraded to the extent that they are no longer useful and functional.

It is to be remembered that this round wire may have a diameter of 0.0625 inches or 4/64 indies.

The description of the manufacture of round wire 40 and the use of round wire 40 in the gun 80 has been presented. It is to be understood that the manufacture and use of round wire 40 has been in existence for a number of years. My consideration of the defect in the round wire 40 and the grooves or indents 74 on the surface of the round wire 40 has been presented With this background, I have developed a wire 100 which, in a lateral crosssectional view, is in the general configuration of a square or a diamond having four flat surfaces 102 and four rounded surfaces 104. Each rounded surface 104 connects with two flat surfaces 102 or each flat surface 102 connects with two rounded surfaces 104. One size of the wire 100 is approximately 0.0625 inches between two opposite rounded surfaces 104 or the width of the wire may be considered to be 0.0442 inches. It is to be understood that the wire 100 may be in different sizes, although a wire having a width of 0.0442 inches is a small wire or small tubular welding electrode.

The wire 100 can be prepared from the lap joint wire 26 or the butt joint wire 30 having a welding flux 24. It is seen that there is a set of dies 106 having indents in the configuration of a V 108 with flat sides 110. A set of these two dies is used to transform the wire 26 or the wire 30 into the wire 100. In actual practice, the wire 26 is drawn through nineteen sets of these dies, or it may be considered that there are nineteen steps to go from the wire 26 or the wire 30 having a diameter of 0.160 inches to the wire 100 having a cross-sectional dimension of about 0.0625 inches.

The wire 100 can be placed into a coil 112. The coil 112 may have a weight of 60 pounds wherein there is a minimum length of about 2,700 feet of wire or may be in a drum of 1,000 pounds and where in there is a minimum length of about 8.5 miles.

Again, at the site of usage of the wire 100 it is necessary to straighten the wire 100 by passing through the three rolls 46 to straighten the wire. The rolls 46 may be a V roll 48 having inwardly recessed surfaces 50 in the form of a V or the rolls 46 may be a roll 52 having an inwardly recessed surface 54. The reason for the straightening rolls 46 is to take out the camber imparted to the wire and also the helical configuration imparted to the wire, as previously explained with respect to the wire 40.

With the wire 100 and of a generally square configuration in a lateral cross-sectional view, it is possible for the straightening rolls 46 to get a better hold or bite onto the wire if the straightening rolls 46 have a V-configuration with V surfaces 50. These rolls can get a better hold or a better bite on the wire 100 and therefore make it possible to more readily take the camber out of the wire 100. As contrasted with this, the straightening rolls 46 and the round wire 40 in the V-configuration with the V sides 50, it is not possible to get usch a good bite or good hold on the wire 40 and therefore it is more difficult to remove the camber frαn the wire 40 than from the wire 100. This also carries over to the drive rolls 60 for driving the wire 100 into the gun 80. With the wire 100 it is possible fo the drive rolls 60 to get a better bite or hold and therefore to more readily remove the camber. Again, the drive rolls 60 do not get as good a bite or hold with the circular configuration electrode 40 and therefore cannot as readily remove the camber from the round wire as from the square configuration electrode.

The drive rolls 60 impart grooves or indentations 116 in the flat surfaces 102 of the wire 100. This leaves the rounded surfaces 104 without grooves or indentations. Now, with the wire 100 passing through the gun 80 the flat surfaces 102 with the grooves and indentations do not contact the spring 84 and do not contact the metal contact tip 92. Instead, the rounded portions 104 contact the spring 84 and contact the metal contact tip 92. As the rounded portions 104 are smooth, the wear on the spring 84 and the wear on the metal contact tip 92 is less with the wire 100 as contrasted to the wire 40 having the grooves or indentations 74. In addition, since the surfaces 104 are smooth, there is not the back pressure on the wire 100 as contrasted with the round wire 40 having grooves or indentations 74.

in FIGS. 2, 5 and 6 there is illustrated the feed rolls 60. In FIGS. 2 and 6 there is illustrated the feed rolls 60 with the square tubular welding electrode between these feed rolls. It is seen that the feed rolls contact the flat surfaces of the square tubular welding electrode 100 and imparts serrations to these flat surfaces. Also, it is seen that the rounded corners 104 are not indented or separated by the feed rolls 60.

In FIG. 5 it is seen that the feed rolls 60 contact the surface of the round tubular welding electrode 40 and imparts serrations to the surface. The serrations are imparted at four distinct and separate areas of the round tubular welding electrode 40.

in FIGS. 7 and 9, it is seen that the round tubular welding electrode 40 with the serrated surfaces is inside of the guide spring 84 and the metal tube 82 of the welding gun. Also, it is seen that the indentations 74 on the surface of the round tubular welding electrode 40 are in contact with the guide spring 84 and act as file so as to wear, unduly, the guide spring 84. In FIGS. 8 and 10, there is illustrated the square tubular welding electrode 100 with the flat surfaces 102 inside of the guide spring 84 in the metal tube 82. It is seen that on the flat surfaces 102 that there are indentations 116. Also, it is seen that the flat surfaces 102 and the indentations 116 are not in contact with the guide spring 84. The rounded corners 104 are in contact with the guide spring 84. The rounded corners 104 are smooth and do not, unduly, wear the guide spring 84 in the welding gun. The same comment can be made with respect to the tip of the welding gun and the fact that the rounded corners 104 do not, unduly, wear the tip of the welding gun.

In FIG. 3 there is illustrated another type of feed roll 120. It is seen that there is a shaft 126 and that on each shaft 126 are mounted two feed rolls 120 having an inwardly sloping angular face 122. On the face 122 are serrations 124. There are two sets of shafts 126 and two sets of feed rolls 120 on each shaft. Also, it is seen that there is a square tubular welding electrode 100 being driven by these four feed rolls 120.

In FIG. 4, there is another form of feed roll 130. There is a shaft 136 and on the shaft 136 there is mounted a feed roll 130 which has two angular, inwardly sloping faces 132. On the faces 132 are serrations 104. There are two spaced-apart shafts 136 and two feed rolls 130 which carbine to form a square configuration for being in a driving relationship with a square tubular welding electrode 100.

The serrations 124 and the feed roll 120 and the serrations 134 and the feed roll 130 impart indentations 116 to the flat surfaces 102 of the square tubular welding electrode 100. It is to be realized that the serrations 124 and the serrations 134 would impart indentations 74 onto the surface of the round tubular welding electrode 40 if the round tubular welding electrode 40 were passed through the feed rolls 120 or 130.

From the foregoing it is seen that the square electrode of a crosssectional dimension of 4/64 inches has certain advantages over a round electrode of a diameter of 4/64 inches. For example, with the square electrode there is less investment in making the electrode as compared with the round electrode. To make the square electrode there is required nineteen (19) stations as the square electrode can be rolled. To make a round electrode of 6/64 inch diameter there is required nineteen (19) stations. However, to make a round electrode of 4/64 inch diameter there is reguired thirty-nine (39) stations. It is seen that there are fewer stations to make a square electrode of 4/64 inch cross-section as only nineteen stations are required as against thirty-nine stations for a round electrode of 4/64 inch diameter. Further, in making a square electrode there is less possibility of damaging the electrode as compared with a round electrode of the same cross-sectional dimension. The square electrode must be rolled while the round electrode can be rolled or drawn. In drawing or roll forming, the round electrode there is a much more possibility of rupturing or damaging the metal skin around the welding flux than rolling a square electrode. With the square electrode there is less wear on the rolls than in forming the round electrode. It has been shown that there is less wear on the welding gun, such as the guide spring and the contact with the square electrode. With a filled welding electrode having a metal tube filled with a welding flux it is possible to weld at a much greater rate than with a solid manual electrode having a welding flux on the outside. For example, a solid electrode with welding flux on the outside is used in a manual situation where a person manually welds. In a manual welding situation there is used an average of four (4lbs. to 5 lbs.) pounds to five pounds of welding electrode. With a semi-automatic or semi-automatic welding equipment using a tubular electrode with welding flux in the interior it is possible to use 12 lbs. to 20 lbs. per hour of welding electrode. This can be interperted to mean that a semi-automatic welding apparatus can produce approximately two and on-half to four times as much weld as a person manually welding.

One of the advantages of a welding electrode with a small crosssectional dimension is that it is possible to weld a thinner plate than with an electrode having a larger cross-sectional dimension. For example, a 6/64 inch round tubular voiding electrode needs a 3/8 inch plate in order to weld satisfactorily. A plate of less thickness can not be welded satisfactorily with a semi-automatic welding equipment using a 6/64 inch round tubular welding electrode. Further, with a small cross-sectional dimension it is possible to weld in an "out of position" plate and the welding is not restricted to a down position of a horizontal position.

It is difficult to form a tubular welding electrode of a crosssectional dimension less than 4/64 inches. With my invention, I have found that it is possible to form the square tubular welding electrode 100 in a roll forming process. Then, the electrode 100 can be drawn through a die having an opening 142 or mating dies 140 having openings 142 to form a circular tubular wleding electrode 144 having a metal sheet 146 or a metal foil 146. The round or circular tubular welding electrode 144 is filled with a welding flux 24. The number of steps required to go from a 4/64 inch square tubular welding electrode 100 to a 3/64 inch round tubular welding electrode 144 may be 3 to 4 steps.

The cross-sectional area of a round electrode having a diameter of 4/64 inches is, approximately, 0.0031 square inches. The cross-sectional area of a square electrode having a cross-sectional dimension of 4/64 inches is, approximately, 0.0039 square inches. The cross-sectional area of a round electrode having a 3/64 inch diameter is approximately 0.0017 square inches. It is seen that the round electrode of 3/64 inch diameter has approximately one-half (1/2) the area of a square electrode or a round electrode having a cross-sectional dimension of 4/64 inches. This can be interperted to mean that there can be a higher arc density on a round electrode of 3/64 inch diameter as compared with the round or square electrode having a crosssectional dimension of 4/64 inches. Further, with the smaller round electrode it is possible to weld thinner plate material. Also, it is possible to weld in an "out of position" place such as possibly an over-head position or an angular position and the welding is not restricted to a down hand position or a horizontal position. In other words, the round electrode with a diameter of 3/64 inches is more versital than the electrode, either square or round, having a cross-sectional dimension of 4/64 inches. Further, in process of forming the square electrode of 4/64 inches cross-sectional dimension, first, probably, by a roll forming process, and then forming the round electrode by drawing the square electrode to realize a diameter of 3/64 inches on the round electrode there is less possibility of breaking the metal foil 146 and scaring the electrode 144. To repeat, there is less capital investment in the equipment for making the 4/64 inch cross-sectional dimension square electrode as compared with the 4/64 inch diameter round electrode as fewer stations are required to roll the square electrode as comparing with rolling and drawing the round electrode. It is possible to commercially acquire a round electrode of approximately 3/64 inch diameter but the cost is a high cost, in the range of about $1.25 per pound. One of the reasons for this high cost is the breaking of the metal tube 146 or the metal foil 146 and the scaring and diameter of the electrode 144 along with the large number of stations or stages required to form the round electrode of 3/64 inch diameter. With my process there are fewer stations require and less possibility of damaging or harming the metal tube 146. Therefore, with my process it is possible to make, economically, the 3/64 inch round electrode.

In trying to form a round electrode there is the possibility with dies, of cutting the tube 146 and distorting the tube 146. This is a common failing in the making of a 4/64 inch round tubular welding electrode by starting out with the butt end 32 of the tube 30 or the lap end 28 of the tube 26. If a party will take the butt joint rod 30 or the lap joint 26 and form the square electrode 100 and then draw the square electrode 100 to form the circular or round electrode 144, there is less possibility of cutting and damaging the metal foil 146.

Claims

WE CLAIM:

1., A tubular welding electrode comprising: a. a tube having a wall; b. said wall having a plurality of flat surfaces; c. adjacent said flat surfaces being joined by a curved surface; d. there being a plurality of said curved surfaces; and, e. a flux in the interior of said curved surface.

2. A tubular welding electrode according to claim 1, and said electrode comprising: a. said tube having four flat surfaces; and, b. said tube having four curved surfaces connecting with appropriate said four flat surfaces.

3. A tubular welding electrode according to claim 2, and said electrode comprising: a. said tube in a lateral cross-sectional view having a, generally, square configuration.

4. A method for manufacturing a tubular welding electrode, said method comprising: a. forming a strip of metal into a trough; b. placing a flux in said trough; c. closing the metal of said trough around said flux to form a tube; d. processing said tube into a tube having a plurality of flat surfaces with adjacent flat surfaces joined by a curved surface so as to have a plurality of curved surfaces; and, e. said tube being said tubular welding electrode.

5. A method according to claim 4, and said method comprising: a. processing said tube into a tube having four flat surfaces and four curved surfaces connecting with appropriate said four flat surfaces to form said tubular welding electrode.

6. A method according to claim 5, and said-method comprising: a. said tubular welding electrode in a later cross-sectional view having a, generally, square configuration.

7. A method according to claim 4, and said method comprising: a. processing said tube into an intermediate tube having a plurality of flat surfaces; and, b. processing said intermediate tube into said tubular welding electrode having, in a lateral cross-sectional view, a, generally, circular configuration.

8. A method according to claim 4, and said method comprising: a. processing said tube into an intermediate tube having four flat surfaces and four curved surfaces connecting with appropriate said four flat surfaces; and, b. processing said intermediate tube into said tubular welding electrode having, in a lateral cross-sectional view, a generally, circular configuration.

9. A combination of a welding gun and a tubular welding electrode; I. said welding gun comprising: a. a contact tip for operatively contacting said tubular welding electrode; II. said tubular welding electrode comprising: a. a tube having a wall; b. said wall having a plurality of flat surfaces; c. adjacent said flat surfaces being joined by a curved surface; d. there being a plurality of said curved surfaces; e. a flux in the interior of said surface; and, III. said tubular welding electrode operatively contacting said contact

10. A combination according to claim 9, and said combination comprising: a. said tube having four flat surfaces; and, b. said tube having four curved surfaces connecting with appropriate said four flat surfaces.

11. A combination according to claim 10, and said combination comprising: a. said tube in a lateral cross-sectional view having a, generally, square configuration.

12. A combination according to claim 9, and said combination comprising: a. said welding gun having a tubular guide; and, b. said tubular welding electrode being inside of said tubular guide.

13. A tubular welding electrode produced by the process comprising: a. forming a strip of metal into a trough; b. placing a flux in said trough; d. processing said tube into a tube having a plurality of flat surfaces with adjacent flat surfaces joined by a curved surface so as to have a plurality of curved surfaces; and, e. said tube being tubular welding electrode.

14. A tubular welding electrode produced by the process according to claim 13, and comprising: a. processing said tube into a tube having four flat surfaces and four curved surfaces connecting with appropriate said four flat surfaces.

15. A tubular welding electrode produced by the process according to claim 14, and comprising: a. said tube in a lateral cross-sectional view having a, generally, square configuration.

16. A tubular welding electrode produced by the process according to claim 13, and comprising: a. processing said tube into an intermediate tube having a plurality of flat surfaces; and, b. processing said intermediate tube into said tubular welding electrode having, in a lateral cross-sectional view, a, generally, circular configuration.

17. A tubular welding electrode produced by a process according to claim 13, and comprising: a. processing said tube into an intermediate tube having four flat surfaces and four curved surfaces connecting with appropriate said four flat surfaces; and, b. processing said intermediate tube into said tubular welding electrode having, in a lateral cross-sectional view, a, generally, circular configuration.

18. A combination of drive rolls and a tubular welding electrode: I. said drive rolls comprising: a. a driving surface having recessed areas and raised areas for contacting and engaging said tubular welding electrode; II. said tubular welding electrode comprising: a. a tube having a wall; b. said wall having a plurality of flat surfaces; c. adjacent said-flat surfaces being joined by a curved surface; d . there being a plural ity of said curved surfaces; e. a flux in the interior of said curved surface;

III. said drive rolls being in contact with said tubular welding electrode; and, IV. said raised areas being in contact with said flat surfaces and causing indentations in said flat surfaces.

19. A combination according to claim 18, and said combination comprising: a. said tube having four flat surfaces; and, b. said tube having four curved surfaces connecting with appropriate said four flat surfaces.

20. A combination according to claim 19, and said combination comprising: a. said tube in a lateral cross-sectional view having a, generally, square configuration.

21. A combination of a welding gun and a tubular welding electrode, and said combination comprising:

I. said welding gun comprising: a. a contact tip for operatively contacting said tubular electrode; II. said tubular welding electrode being manufactured by a process comprising: a. forming a strip of metal into a trough; b. placing a flux in said trough; c. closing the metal of said trough around said flux to form a tube; d. processing said tube into a tube having a plurality of flat surfaces so as to have a plurality of curved surfaces; e. said tube being said tubular welding electrode; and,

III. said tubular welding electrode operatively contacting said contact tip.

22. A combination of a welding gun and a tubular welding electrode according to claim 21, and said combination comprising: a. processing said tube into a tube having four flat surfaces and four curved surfaces connecting with appropriate said four flat surfaces to form said tubular welding electrode.

23. A combination of a welding gun and a tubular welding electrode according to claim 22, and said combination comprising: a. said tubular welding electrode in a lateral cross-sectional view having a, generally, square configuration.

24. A combination of a welding gun and a tubular welding electrode according to claim 21, and said combination comprising: a. processing said tube into an intermediate tube having a plurality of flat surfaces; and, b. processing said intermediate tube into said tubular welding electrode having, in a lateral cross-sectional view, a, generally, circular configuration.

25. A combination of a welding gun and a tubular welding electrode according to claim 21, and said combination comprising: a. processing said tube into an intermediate tube having four flat surfaces and four curved surfaces connecting with appropriate said four flat surfaces; and, b. processing said intermediate tube into said tubular welding electrode having, in a lateral cross-sectional view, a , generally, circular configuration.