The invention comprises an apparatus for removing from the outer surface the raised bead resulting from welding in the manufacture of continuous seam-welded metal tubes. A stage or travelling support block mounted for movement transversely of the advancing tube carries a pair of scarfing blades, each of which may have a plurality of cutting edges moveable seriatim into operative position. Adjusting screws operatively connected to the stage permit the stage and the scarfing blades thereon to be manually adjusted both laterally and vertically relative to the tube, and to selectively position either one of the scarfing blades for bead removal. A piston rod is connected by suitable linkage to the stage for rapidly advancing and retracting the stage upon command to move the scarfing blade into and out of operative position.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates generally to the manufacture of continuous 
seam-welded metal tubes or pipes, and more particularly to a novel 
apparatus for scarfing or removing from the outer surface of the tube or 
pipe the raised bead or flash resulting from welding of the seam. 
2. Description of the Prior Art 
In accordance with a well-known process for producing seam-welded pipes and 
tubes, a continuous strip or skelp is advanced through forming apparatus 
and progressively deformed into a tubular form having an open, 
longitudinally extending seam. The tubular form then advances through a 
welding station wherein the adjacent longitudinal edges are urged together 
and joined by a suitable welding process. The particular welding process 
employed will generally be indicated by the material from which the tube 
or pipe is formed, for example, low carbon steel, stainless steel, 
aluminum, etc., and may include any of the well-known welding techniques 
conventionally employed with the different materials. In a preferred 
process the tube or pipe is heated by electrical induction so that the 
edges achieve fusion temperature, and the heated edges are forced together 
to produce a continuous monolithic weld of the seam. As a result of the 
pressure applied in forcing the heated edges together to achieve fusion, 
the material bulges both outwardly and inwardly to create a raised bead or 
flash extending along the longitudinal weld seam. In seams formed by other 
types of welding such as arc welding and gas welding, a similar raised 
bead or seam is generally formed along at least the outer surface of the 
tube. 
In order to produce a commercially acceptable product, it is generally 
necessary to remove the protruding portion of the weld bead or flash flush 
with the surface of the tube or pipe. Various devices have been proposed 
heretofore for removing both the internal bead and the external bead. 
Removing the internal bead is, of course, more difficult than removing the 
external bead due to the restricted access to the removal area. A scarfing 
tool particularly suited for removing the internal bead is disclosed in 
U.S. Pat. No. 4,600,180, issued Jul. 15, 1986. Removal of the external 
bead can be accomplished by any of a number of conventional processes 
including grinding and scarfing. One type of external surface scarfing 
apparatus is described in U.S. Pat. No. 3,249,349, issued May 3, 1966. 
While a number of devices have been employed heretofore in removing or 
scarfing the external weld bead from seam welded pipe or tubing, those 
prior art devices have not proved entirely satisfactory for the present 
day high speed production of continuously formed seam welded pipe or 
tubing. It is highly desirable to remove the weld bead immediately 
following the welding procedure, while the bead and pipe retain sufficient 
heat from the welding process and remain at the proper temperature for 
scarfing. The apparatus should also be able to evenly and accurately 
remove the bead or flash for extended periods of time without requiring 
interruption of operation of the line for the continuous production of the 
seam welded tubes or pipes. The devices heretofore available have lacked 
the capability to quickly and readily adapt to changes in operation while 
permitting continuous operation of the tube forming apparatus. 
SUMMARY OF THE INVENTION 
In accordance with the present invention the aforementioned deficiencies of 
the prior art devices are overcome by providing a scarfing apparatus which 
can function as an individual unit in a tube forming apparatus, or which 
can be employed as one of a series of two or more such units disposed in 
tandem along a tube forming line and rapidly and selectively moved into 
and out of operation in conjunction with others of the units to provide 
continuous accurate removal of the weld bead or flash. A stage or 
travelling support block mounted for movement transversely of the 
advancing newly formed tube carries at least two replaceable scarfing 
tools adapted for selective positioning of a selected one of the scarfing 
tools in operative position relative to the advancing tube. Each tool may 
have a plurality of cutting surfaces for movement into scarfing position 
one after another as the cutting surfaces become worn. The apparatus 
includes mechanism for moving the scarfing tools toward and away from the 
tube to precisely position the cutting surface of the tool relative to the 
tube surface from which the weld bead is to be removed, and linkage 
mechanism is provided for rapidly moving the scarfing tool between 
operative and retracted inoperative positions in response to an 
appropriate signal. The bead is removed as a continuous strip and wound 
upon a reel positioned above the advancing tube for disposal. 
It is therefore an object of the invention to provide an improved apparatus 
for scarfing the raised weld bead or flash from the outer surface of a 
longitudinal seam welded tube. 
Another object of the invention is to provide such an apparatus capable of 
producing an improved scarfed seam on seam welded tube. 
Still another object of the invention is to provide an apparatus for 
precisely removing the raised weld bead from continuously produced 
longitudinal seam welded tubing for extended periods of time without 
significant interruption of the production process. 
Other objects and advantages of the invention will become more apparent 
during the course of the following description, when taken in connection 
with the accompanying drawings

DESCRIPTION OF THE PREFERRED EMBODIMENT 
There is shown schematically at 10 in FIG. 1 a portion of a conventional 
tube forming mill for continuously producing a cylindrical seam-welded 
metal tubing 11. In such mills a metal strip or skelp is continuously 
withdrawn from a supply (not shown) and advanced through a series of 
opposed forming rolls 12 and side closing rolls 13 whereby it is 
progressively bent into tubular form. The formed blank then advances 
through a welding station 14 wherein the seam is suitably welded to 
produce a continuous seam-welded tube having, incident to the welding, a 
raised bead or flash 15 extending longitudinally along its outer surface. 
The tube then passes through a scarfing unit 17 for removal of the raised 
bead. As indicated hereinabove and as illustrated in FIG. 1, two or more 
of the scarfing units 17 may be located in tandem along the production 
line to permit alternate use of the units. Thereafter, the tube may be 
advanced through additional traction and working roll units 18 (only one 
shown) for final working prior to being cut into units of desired length 
or otherwise prepared for shipment to customers. 
As indicated above, it is contemplated that the seam of the tube can be 
welded by any of the well-known welding processes suitable for the 
particular material from which the tube is formed. According to a widely 
used procedure as illustrated in FIGS. 1 and 2, the tube is heated by 
induction and the edges of the tube are urged against one another while 
the material is at a sufficiently high temperature to cause them to fuse 
together. To that end, at the welding station 14 as will be seen in FIG. 
1, the formed tube 11 passes through an induction coil 19 of an induction 
heating unit 20. The heated tube immediately enters a roller press 22 
where it passes between opposed side rolls 23 and beneath angularly 
disposed press rolls 24 which force the edges of the confined tube 
together. As a result of the temperature of the tube material and the 
pressure applied by the rolls 23 and 24, the edges of the formed tube fuse 
together at their interface and the material bulges outwardly along the 
seam to create the continuous raised bead 15. The material also may bulge 
inwardly to create an interior bead 25 (FIG. 2). 
Immediately following welding and formation of the bead 15, and while 
remaining at nearly the fusion temperature, the tube enters the scarfing 
unit 17. As illustrated generally in FIG. 3, the novel scarfing unit of 
the invention includes a base plate 27 anchored as by bolts 28 to a base 
structure 29. In order to support and guide the tube through the scarfing 
units, a support roll 30 is positioned beneath the tube opposite the point 
at which the bead 15 is removed. The tube passes between cooperating, 
opposed upper and lower guide rolls 32 and 33, respectively, disposed 
adjacent the support roll. Each of the support and guide rolls is 
configured with a curved circumferential peripheral surface 34 (FIGS. 6 
and 7) particularly adapted to accommodate substantially one-half the 
circumferential surface of the tube 11, and to thus guide the pipe along a 
precise predetermined path through the unit. 
In order to permit the scarfing units to be readily changed to accommodate 
tubes of different diameters, provision is made for quickly and simply 
removing and replacing the rolls 30, 32 and 33. To that end, the roll 30 
is conventionally journalled for rotation within a clevis 35 which, in 
turn, is removably received within a recessed portion 37 of an upstanding 
bracket 38 affixed to the base plate 27. At its closed and the clevis is 
adapted to be supported upon shims 39 resting upon the base plate and of 
suitable thickness to support the roll at the proper elevation. The clevis 
is held within the recess 37 by retainer plates 40 adjustably secured to 
the legs of the bracket 38 by bolts 42 extending through elongated 
openings 43 in the plates. Thus, the support roll 30 can be exchanged by 
merely loosening the bolts 42, sliding the retainer plates 40 outwardly 
and removing the clevis 35 carrying the support roll. Another clevis 
having the appropriate support roll journalled therein is inserted into 
the recess 37, and suitable shims 39 are positioned beneath the clevis to 
position the roll at the desired height. The retainer plates are then 
moved inwardly and the bolts are tightened to complete the exchange. 
The guide rolls 32 and 33 are similarly journalled for rotation within 
mounting frames or clevises 44 removably carried within a recess 45 of a 
support bracket 47 affixed to the base plate 27. The mounting frames 
carrying the rolls 32 and 33 are secured within the recess by retainer 
plates 48 adjustably secured to the legs of the support bracket 47 by 
bolts 49 extending through horizontally elongated openings (not shown) in 
the plates. In order to provide for proper vertical positioning of the 
rolls 32 and 33, the lower mounting frame 44 is supported upon shims (not 
shown) in a manner similar to the clevis 35, and the upper mounting frame 
44 is adapted for vertical sliding movement within the recess 45. An 
adjusting screw 50 is connected to the top of the upper mounting frame 44 
as by a swivel connector 52 threaded into or otherwise removably coupled 
to the mounting frame. The adjusting screw extends through and is in 
threaded engagement with a block 53 affixed atop the support bracket 47, 
and is provided at its upper end with a rotary hand wheel 54. Thus, by 
suitably turning the hand wheel the mounting frame 44, and hence the guide 
roll 32 carried thereby, can be vertically adjusted relative to the guide 
roll 33 for accommodating the tube 11 passing therebetween. The rolls 32 
and 33, as with the roll 30, can be readily removed and replaced by 
disconnecting the swivel connector 52, loosening the bolts 49, and 
retracting the retaining plates 48 to remove the clevises 44. Replacement 
rolls can then be installed by reversing the procedure. 
The scarfing or bead removal mechanism of the invention, identified 
generally at 55, is carried by a pair of side plates 57 disposed on 
opposite sides of the path of the tube 11 The side plates are positioned 
between the brackets 38 and 47 and affixed at their lower end to the base 
plate 27, and are interconnected at their upper end by a cross bar 58. As 
will be hereinafter described, the novel scarfing units include provision 
for precisely adjusting the cutting blade both vertically and laterally 
relative to the tube 11, quickly advancing and retracting the cutting 
blade into and out of operative position, and moving alternate blades into 
and out of operative position for replacement of the cutting edge with a 
minimum interruption in production. 
To that end, there is affixed to each of the side plates 57 a vertically 
extending side rail 59 having a slideway 60 formed therein. A lower 
mounting block 62 includes oppositely disposed wings 63 configured for 
reception within the slideways whereby the mounting block is adapted for 
movement vertically along the side rails 59. A U-shaped carrier 64 
positioned above the mounting block 62 likewise includes oppositely 
disposed wings 65 configured for reception within the slideways so that 
the carrier can be readily moved to selected vertical positions along the 
side rails 59. 
As will be hereinafter explained, the mounting block 62 is coupled to the 
carrier 64 and the carrier serves to both precisely position the mounting 
block, upon which the cutting tools are carried, in operative position 
relative to the tube and bead or seam 15, and to quickly move the cutting 
tool into and out of operative position. More particularly, a boss 67 
extending rearwardly from the carrier 64 has connected thereto a threaded 
shaft 68 of a screw jack 69. The screw jack is secured as by bolts 70 
(FIG. 6) to a mounting plate 72 extending between and affixed to the side 
plates 57. An operating shaft 73 conventionally coupled to the screw jack 
extends through a bearing 74 in the side plate 57 and has a hand adjusting 
wheel 75 at its end. Thus, by appropriately manipulating the hand wheel 75 
the screw jack 69 is operated to advance the threaded shaft 68 
therethrough and correspondingly raise or lower the carrier 64. 
In order that the lower mounting block 62 may move up and down with the 
carrier 64 and, as well, be raised and lowered relative to the carrier, 
the block and carrier are interconnected as by linkage identified 
generally at 77. More particularly, the mounting block 62 includes a boss 
78 to which a pair of links 79 are pivotally connected by a pin 80. At 
their opposite end the links are pivotally connected by a pin 82 to an arm 
83. The arm is keyed to a shaft 84 rotatably mounted in bearings 85 
carried within each of a spaced pair of walls 87 comprising the flanges of 
the U-shaped carrier 64. A bracket 88 is affixed to the appropriate one of 
the walls 87 of the U-shaped carrier as by stud bolts 89. A flange 90 
projecting upward at the outer end of the bracket carries a bearing 92 
within which the end of the shaft 84 is rotatably journalled. There is 
also affixed to the bracket 88 as by stud bolts 93 a conventional fluid or 
electromechanically activated cylinder assembly 94 having a reciprocable 
piston rod 95. Suitable means (not shown) is provided for actuating the 
cylinder to selectively extend and retract the piston rod in the 
conventional manner. At its distal end the piston rod is pivotally 
connected by a pin 97 to spaced arms 98 of a crank member 99 keyed to the 
shaft 84 so as to rotate the shaft in response to extension and/or 
retraction of the piston rod. 
Thus, as will be seen in FIG. 3, with the piston rod extended the crank 
member 99 will rotate the shaft 84 to a position where the arm 83, links 
79 and lower mounting block 62 will be in the positions shown in solid 
lines. When the piston rod is retracted the crank member 99 will be 
rotated clockwise as viewed in FIG. 3, swinging the arm 83 and links 79 to 
the position shown in broken lines and consequently raising the lower 
mounting block 62 and cutting tools carried thereby to the position 
partially shown in broken lines. 
The bead 15 is removed from the tube by a cutting assembly shown generally 
at 100 affixed to the lower mounting block 62. As heretofore indicated, an 
important feature of the invention is that the blade which removes the 
bead can be precisely positioned both laterally and vertically relative to 
the tube, and an alternate blade can be quickly moved into operative 
position to permit replacement of worn cutting surfaces with a minimum 
inconvenience to the continuing operation of the tube facility. To that 
end, the cutting assembly comprises a bed plate 102 affixed to the lower 
mounting block 62 and including a raised flange 103 extending transversely 
of the tube 11 and having oppositely disposed undercut side walls 104. A 
travelling support block 105 is provided in its rear surface with a mating 
recess 107 for receiving the raised flange and providing for sliding 
movement of the travelling support block along the bed plate. As best seen 
in FIG. 4, in order to provide for sliding movement of the support block 
to selected positions relative to the bed plate 102, a lead screw 108 is 
threadably received within a threaded opening 109 extending longitudinally 
through the bed plate. The lead screw is rotatably mounted within a 
bushing 110 carried by a plate 112 extending along an edge of the 
travelling support block, and a hand wheel 113 is affixed to the end of 
the lead screw adjacent the bushing. Thus, by appropriately manipulating 
the hand wheel 113, the lead screw can be advanced and retracted through 
the mounting block 62 to move the travelling support block 105 to selected 
lateral positions. 
The blade which separates the bead 15 from the tube 11 is preferably 
inclined downwardly and forwardly toward the advancing tube as illustrated 
in FIG. 3 so that the cutting edge cleanly severs the bead material from 
the tube. In order to achieve the desired angle of inclination, there is 
affixed to the travelling support block 105 a wedge block 114 having an 
inclined bearing surface 115. One or more scarfing blade holders 117 are 
affixed to the wedge block and along the bearing surface as by a cover 
plate 118 secured by stud bolts 119 extending through the blade holders 
and threaded into the wedge block. In order to enable alternate scarfing 
blades to be moved into operative position, at least two such blade 
holders are preferably mounted at laterally spaced positions along the 
wedge. 
As will be seen in FIGS. 5 and 7, the blade holders 117 are recessed at 
their lower end as at 120 for receiving a scarfing blade 122 and a 
retainer plate 123. While the scarfing blade itself may comprise any of a 
number of well-known such devices, in its preferred form the blade is a 
so-called star blade of hexagonal configuration and having six individual 
cutting edges 124 disposed around its perimeter. The blade is rotatably 
affixed to the holder 117 by a suitable fastener 125 so that a fresh 
cutting edge can be moved into operative position as necessary by rotating 
the blade until each of the edges has been used. The retainer plate 123, 
removably secured in place by stud bolts 125 extending therethrough and 
threaded into the blade holder, is configured so that its lower end 127 
engages the cutting edge 124 diametrically opposite the cutting edge in 
operative position to secure the scarfing blade against rotation. Thus, to 
bring a fresh cutting edge 124 into operative position, the bolts 125 are 
merely loosened or removed so that the retainer plate 123 can be 
disengaged from the adjacent cutting edge. The scarfing blade is then 
rotated to the desired position, and the retainer plate is tightened to 
affix the blade in this position. 
The scarfing blade severs the raised bead from the advancing tube 11 in the 
form of a continuous ribbon of material 128. In order to collect the 
ribbon with a minimum of inconvenience, there is mounted on a pedestal 129 
above the scarfing mechanism 55 a winding reel 130 suitably propelled by a 
drive unit 132 (FIG. 1). The ribbon 128 is directed upwardly as it is 
severed from the tube and over a guide roller 133 rotatably carried by a 
mounting bracket 134 affixed to the U-shaped carrier 64 for winding upon 
the reel 130. When the reel becomes filled the ribbon is severed and the 
accumulated material removed from the reel or the filled reel is replaced 
by an empty reel, and the severed end of the ribbon is attached to the 
reel to again begin accumulating thereon. 
Briefly reviewing a preferred manner of operating the novel scarfing unit, 
with the piston rod 95 retracted to move the cutting assembly 100 to its 
raised, inoperative position, a selected scarfing blade 122 is adjusted to 
bring a desired cutting edge 124 into operative position. The travelling 
support block 105 is moved laterally by manipulating the hand wheel 113 to 
approximately align the cutting edge with the bead 15 on the tube 11 as it 
advances through the mill. The elevation of the guide rolls 32 and 33 may 
be adjusted as necessary by manipulating the adjusting wheel 54 to insure 
that the tube is properly seated within the curved peripheral surface 34 
of the support roll 30. Anticipated vertical positioning for the cutting 
edge 124 may be approximated by suitably manipulating the hand wheel 75 to 
raise or lower the carrier 64 to a selected position. The cylinder may 
then be actuated to extend the piston rod 95 and lower the mounting block 
62, thereby moving the cutting edge 124 of the scarfing blade into 
operating position. The blade is then precisely positioned vertically and 
laterally relative to the bead and tube seam by means of the adjusting 
wheels 75 and 113, and the ribbon 128 is entrained over the guide roller 
132 and onto the winding reel 130. 
When the cutting edge 124 currently in use becomes dulled or otherwise 
requires replacement, the cylinder is actuated to quickly raise the 
cutting assembly out of operative position and the support block 105 is 
moved laterally by means of the wheel 113 to bring the other of the blade 
holders 117 having a scarfing blade 122 with a fresh cutting surface 124 
in operative position, into alignment with the seam of the tube. The 
cutting assembly is then lowered by actuating the cylinder 94, and the 
position of the scarfing blade 122 is adjusted as necessary by means of 
the wheels 75 and 113 to precisely locate the cutting edge 124. As will be 
readily apparent, the cutting edge may thus be replaced and precisely 
adjusted with very little interruption in production. Of course, if two of 
the scarfing units are located in tandem as illustrated in FIG. 1, 
replacement can be accomplished with no interruption in production. 
It is to be understood that the form of the invention herewith shown and 
described is to be taken as an illustrative embodiment only of the same, 
and that various changes in the shape, size and arrangement of parts may 
be resorted to without departing from the spirit of the invention.