FR2525511A1 - Removing burrs in butt resistance welding of pipes - using clamp body having jaws mounting deburring cutters whichconform to cross=section of pipes - Google Patents

Abstract

Appts. for removing burrs in butt resistance welding of workpieces comprises a clamping body having jaws for gripping the workpiece and a clamping cylinder for actuating the jaws. Deburring cutters are mounted on the jaws and are pivotally interconnected. Hydraulic actuators are used for pressing the cutters against the workpiece and are mounted on the jaws symmetrically relative to the workpiece. Used for removing burrs in butt resistance welding of pipes when laying main pipelines. (First major country equivalent to AT8201510-A) (Previously notifed in Week 8345).

Description

 The present invention relates to welding and in particular relates to a device for deburring parts welded by resistance with the help of welding machines of the clamp type.

 The invention has the most advantage for the resistance butt welding of tubes when laying pipelines.

 The devices used to remove burrs when welding end pieces by resistance have been known for a relatively long time, but no device of this kind has been created up to now ensuring quality deburring without this affecting the yield of the welding process of different profiles, in particular that of resistance butt welding of tubes.

 There are known devices for deburring welded joints of rails, tubes, steel profiles and the like (see, for example, United States patents of invention No. 3081673, 3336839, French patent NO 1417444, Japanese loebrevets NO.NO. 46-8568 and 45-29092).

The devices in question include a group of burr cutting tools, the cutting edges of which form the cross-sectional profile of the part. These cutting tools are kinematically connected to a mechanism for clamping the tools against the surface of the workpiece and to a control for their movement along said workpiece.

 However, these devices are mounted separately from the welding machine and cut the already cooled burr, which considerably affects the efficiency of the process.

This drawback is largely eliminated in a device used for deburring end-welded rails (see author's certificate)
USSR NO 697275). This device is mounted on one of the movable bodies of the clamp type welding machine, which body simultaneously constitutes the frame of said device. This frame consists of two parts which can deviate from each other from the vertical axis of the part and is in the form of a clamp with two macho ires connected together at their upper part by a clamping cylinder on the rod of which is fixed a crosspiece. In the lower part of said jaws are mounted an upper cutting tool and two lateral ones, the cutting edges of which form the cross-sectional profile of the part (rail). The two lateral tools are articulated on axes which are rigidly fixed to said jaws.

The cutting tools mentioned are arranged symmetrically with respect to the vertical axis of the rail.

 The device is provided with a mechanism for clamping the cutting tools against the surface of the rail. This mechanism is in the form of a stop which is fixed on said cross member and kinematically connected to the upper cutting tool, the latter being in turn articulated with the lateral cutting tools.

 The device which has just been described makes it possible to deburr the welded joint along the entire perimeter of the rail immediately after the welding operation. However, such a device ensures high quality deburring and high efficiency only in the case of deburring of rails. For tubes or box parts, as well as for U-shaped sections, changing the position of the cutting tools in order to adapt it to the profile of said parts cannot ensure high quality deburring.

 This is explained by the deformation of said parts during their tightening in the body of the welding machine.

As a result, the edges of the cutting tools do not closely embrace the part along its perimeter, hence the absence of the essential clearance between the cutting edges and said surface of the part being treated. In turn, the decline in the quality of deburring results in a decrease in the efficiency of the entire welding process. This is explained by the fact that it is necessary to carry out additional treatment of the welded joint.

 On the other hand, during the deformation of the workpiece surface (during its tightening), the deformation forces act on the cutting tools and, as a result, are transmitted to the axes which are rigidly fixed to the jaws of the device. This results in a reduction in the reliability of said device, due to the risk of rupture of said axes.

 Thus, the device described is only effective when welding rails, which significantly reduces its field of application.

 It has therefore been proposed to develop a device for deburring end-welded parts by resistance, the mechanism for clamping the cutting tools against the surface of the part would significantly expand the technical possibilities of said device without affecting the quality of deburring and the efficiency of the welding process.

 This problem is solved with the aid of a device for deburring resistance welded parts, of the type comprising a frame which, being composed of two parts which can deviate from one another from the vertical axis of the workpiece, is in the form of a clamp having two jaws connected to each other, at their upper part, by a clamp cylinder # ge, while in the lower part of said jaws are fitted with cutting tools for removing burrs, the cutting edges of which form the cross-sectional profile of the part, as well as a mechanism for clamping said tools against the surface of the part, characterized, according to the invention, in that that the mechanism for clamping the cutting tools against the surface of the workpiece is in the form of a system of hydraulic cylinders mounted on said jaws in a symmetrical manner with respect to the vertical axis of the collet, the rods said hydraulic cylinders being connected kinematically only to the respective cutting tools and the cutting tools mounted on the same jaw being hinged together.

 Such a design of the mechanism for clamping cutting tools against the surface of the workpiece makes it possible to apply these tools tightly against the deformed surface of the workpiece so that there is a minimum clearance between them. Under these conditions, the hydraulic cylinders withstand the considerable efforts of removing the part when it is tightened. These #vantages allow the claimed device to be used efficiently with a view to devising parts of different cross section, especially parts such as tubes, products in boxes, etc. This considerably widens the technical possibilities of the device, while ensuring high quality deburring and high efficiency of the welding process and good reliability of the dispostft itself.

 When welding in the factory or in a tube welding workshop, it is rational that the mechanism for clamping the cutting tools against the workpiece surface is in the form of two cylinders, each of which is fixed to the jaw corresponding, the rod of each of said hydraulic cylinders being rigidly connected to the midpoint of a lever with two arms, the arms of which are articulated to the corresponding cutting tools.

 Under these conditions, the increase in the size of the welding machine has no effect on its reliability and on its convenience of use. The use of only two hydraulic cylinders considerably simplifies the structure of the device.

On the contrary, in the case of a traveling welding machine, when the size of the welding machine is of great importance, it is rational that the mechanism for clamping the cutting tools against the workpiece surface is achieved bare form of four hydraulic cylinders articulated at the rate of two on each of the jaws, and that the rods of said hydraulic cylinders are articulated with the corresponding cutting tools, the
tools for cutting each pair of cylinders being
articulated among themselves.

The invention will be better understood and other aims,
advantages and details of it will appear better at
in the light of the explanatory description which will follow from
several embodiments given only as
of nonlimiting examples with references to the drawings not
annexed limitative in which
- Figure 1 is an overview of a machi
pliers type weld with deburring device
rabies according to the invention;
- Figure 2 shows an embodiment
of the device according to the invention comprising two cylinders
hydraulic, shown in the position where the tools
of cutting enclose the part (cutting along Il-Il of the fi
gure 1);
- Figure 3 shows the device of the fi
gure 2, but in position separated from the jaws ;;
- Figure 4 shows the embodiment
in # L # The device has four hydraulic cylinders,
in the position where the cutting tools grip the work
(section along line IV-IV of Figure 1);
- Figure 5 shows the device of the
Figure 4, but in the separated position of the jaws.

The device for deburring resistance welded parts is mounted on the movable body I
(see Figure 1) of a clamp type welding machine, said body ooEitantà turn the frame of the device itself. The clamp type welding machine has two
body 1 and 2 which are fixed on the same axis 3. The body 2
fixed on axis 3 is axially stationary, while the
body I is mounted on a socket (not shown) engaged
on said axis 3 so as to slide axially on this
latest. This axial movement is ensured by cylinders
hydraulics 4 whose rods 5 connect the two bodies of
the welding machine.

Each of the bodies 1 and 5 of the machine is in the form of a collet consisting of two parts which can deviate from each other from the vertical axis of the part (for example of # n tube 6) and have two jaws 7 and 8 (see Figures 2 and 55) connected to each other at their upper part by a hydraulic clamping cylinder 9. On the rod 10 of the clamping cylinder
9 is fixed a cross member II to which are articulated rods 12 and 13 articulated to the jaws 7 and 8, respectively.

 Each of the jaws 7 and 8 is provided with a jaw 14 having, in the case considered here by way of example, a cylindrical working surface whose radius is equal to that of the part (tube 6) to be welded.

 Welding transformers 15 are electrically connected to the jaws 14 in the jaws 7 and 8 of the body 2 (see FIG. 1 of the drawings).

 The claimed device also comprises cutting tools 16, 17, 18 and 19 (see FIG. 2) used to remove the burrs and mounted in the lower part of said jaws 7 and 8 of the body I, and a mechanism 20 for clamping said tools cutting against the surface of the tube 6.

 The cutting tools 16, 17, 18 and 19 used to remove the burrs are mounted so that their cutting edges form the cross-sectional profile of the part (tube 6). The cutting tools 16 and 17 arranged on the jaw 7 and the tools 18 and 19 arranged on the jaw 8 are connected together by joints 21.

 The mechanism 20 for clamping the cutting tools 16, 17, 18 and 19 against the surface of the tube 6 is, according to the invention, in the form of a system of hydraulic cylinders which are mounted on the jaws 7 and 8 of symmetrically with respect to the vertical axis of the body 1 and which have their rods kinematically connected to the respective tools 16, 17, 18 and 19.

 Figures 2 and 3 show an embodiment in which the mechanism for clamping the cutting tools against the surface of the workpiece (tube 6) is produced in the form of two hydraulic cylinders 22 and 23. the hydraulic cylinder 22 is fixed on the jaw 7 and has a rod 24 rigidly connected to the midpoint of a lever 25 with two arms.

The arms 26 and 27 of this lever are articulated by means of rods, respectively 28 and 29, to the cutting tools 16 and 17, respectively.

 The hydraulic cylinder 23 is fixed on the jaw 8 and its rod 30 is rigidly linked to the midpoint of another lever with two arms, designated at 31. The arms 32 and 33 of the lever 31 are articulated by means of rods 34 and 35, respectively, to cutting tools 18 and 19, respectively.

 In Figure 2, the device according to this embodiment has its cutting tools 16, 17, 18 and 19 applied to the surface of the workpiece (tube 6). In FIG. 3, the jaws 7 and 8, as well as the cutting tools 16, 17, 18 and 19, are separated.

 FIGS. 4 and 5 represent another embodiment, # s leqSL the mechanism 20 for clamping the cutting tools 16, 17, 18 and 19 against the surface of the part (tube 6) is in the form of four hydraulic cylinders 36, 37, 38 and 39 mounted at a rate of two on each jaw 7 and 8. The hydraulic cylinders 36 and 37 are articulated to the mAchDire 7 and have their rods, respectively 40 and 41, perpendicular to the vertical axis of the body 1 and connected by articulations to the cutting tools, respectively 16 and 17, which are in turn articulated to one another by means of an articulation 21.

 The hydraulic cylinders 38 and 39 are articulated to the jaw 8 and have their rods, respectively 42 and 43, also perpendicular to the vertical axis of the body 1 and coaxial with the rods, respectively 40 and 41. Said rods 42 and 43 are connected by articulations to the cutting tools, respectively 18 and 19, which, in turn, are articulated to one another by means of another articulation 21.

 In FIG. X, the cutting tools 16, 17, 18 and 19 of the device according to this embodiment enclose the part (tube 6), while in FIG. 5, said cutting tools are in the separated position.

 The deburring device which has just been described operates in the following manner.

 In the starting position, under the effect of the clamping cylinder 9, the body (clamp) 1, as well as the body 2, are in the open position (see Figures 1, 3 and 5).

 After installing the welding machine on the workpiece (tube 6), the clamping cylinder 9 brings the jaws 7 and 8 closer to each other (see Figure 2). This operation concerns the body 1 as well as the body 2. Then the rod 10 of the jack 9 moves jointly downwards with the cross-member 11. The links 12 and 13 pivot in taking a position closer to the horizontal and, by there, move the upper parts of the jaws 7 and 8 away from the vertical axis of the body 1 by rotating them around the axis 3. At the same time, the lower parts of the jaws 7 and 8 approach one another and the jaws 14 enclose the part (tube 6). Due to the approximation of the lower parts of the jaws 7 and 8, the cutting tools 16, 17, 18 and 19 also come closer.

 Simultaneously with the clamping of the part (tube6) between the jaws 14, the rods 24 and 30 of the hydraulic cylinders, respectively 22 and 23, begin to move.

The rods 24 and 30 act by means of the two-arm levers 25 and 31 on the cutting tools 16, 17, 18 and 19 which pivot around the joints while coming to be applied on the peripheral surface of the part.

 Once the welding operation is complete, the end part of the part (tube6) enclosed in the strokes I is released from the jaws 14 by removing the pressure in the clamping cylinder 9. Then the jaws 14 do not open completely , but so as to be able to slide on the face of the part (tube 6).

 Then the hydraulic cylinders 4 are started up, the rods 5 of which bring the body 1 closer to the body 2 of the machine. In doing so, the cutting tools 16, 17, 18 and 19 remove the burrs from the welded joint along the entire periphery of the part (tube 6).

 After deburring, the rods 24 and 30 of the hydraulic cylinders 22 and 23 begin to move away from the workpiece (tube 6) by rotating the cutting tools 16, 17, 18 and 19 around the joints 21, so that these tools also separate from the workpiece surface (tube 6) (see Figure 3). Simultaneously begins the loosening of the part by means of the jack 9 until the jaws 7 and 8 open completely. This operation being completed, the welding machine is removed.

 The device according to the embodiment shown in Figures 4 and 5 operates essentially in the same way.

 However, simultaneously with the tightening of the workpiece (tube 6) erlrelesmars 14> oe ## àsed # Sia # lestiges 40,41, 42and 43 hydraulic cylinders, respectively 36, 37, 38 and 39. These rods act on the tools section 16, 17, 18 and 19 which, by pivoting around the joints 21, are applied to the part (tube 6) along its perimeter.

 The deburring operation being completed, the rods 40, 41, 42 and 43 of the hydraulic cylinders 36, 37, 38 and 39 begin to move away from the workpiece (tube 6) by rotating the cutting tools 16, 17 , 18 and 19 around their joints 21, so that these tools separate from the surface of the part (tube 6).

Claims (3)

R E V E N D I C A T I O N S  1. Device for the cleaning of parts end-welded by resistance, of the type comprising a frame (1) comprising two parts which can deviate from one another from the vertical axis of the part to be treating, said frame being in the form of an earth clamp having two jaws (7) and (8) connected to each other at their upper part by a clamping cylinder (9), as well as cutting tools (16), (17), (18) and (19) for removing burrs, mounted in the lower parts of said jaws and whose cutting edges form the cross sectional profile of the part, and a mechanism (20) for clamping the tools cutting (16), 17), (18) and (19) against the surface of the workpiece, characterized in that the mechanism (20) for clamping the cutting tools and (17), (18) and (19 ) against the surface of the part to be treated is produced in the form of a system of hydraulic cylinders (22) and (23) mounted on the jaws (7) and (8) in a symmetrical manner with respect to the vertical axis of the frame (1), the rods (24) and (30) of said hydraulic cylinders (22) and (23) being kinematically connected to the cutting tools (16), (17), (18) and (19 ) corresponding #, the cutting tools (16) and (17), (via) and (19) mounted on the same jaw, respectively (7) and (8), being articulated to each other.  2. Device according to claim 1, characterized in that the mechanism (20) for clamping the cutting tools (16), (17), (18) and (19) against the surface of the part to be treated is in the form of two hydraulic cylinders (22) and (23) each of which is fixed to the corresponding jaw (7), (8), the rod (24), (30) of each of the hydraulic cylinders (22), (23) being rigidly connected at the midpoint of a lever with two arms (25), (31) whose arms (26) and (27), (32) and (33) are articulated with the corresponding cutting tools (16) and (17), (18) and (19).  3. Device according to claim 1, characterized in that the mechanism (20) for clamping the cutting tools (16), (17), (18) and (19) against the surface of the workpiece is in the form four hydraulic cylinders (36) (37) and (38), (39) articulated at the rate of two to each of the jaws (7) and (8) and whose rods (40), (41), and (42) , (43) are articulated to the cutting tools, respectively (i6), (17) and (18), (19), the cutting tools (16), (17) and (18), (19) of each of pairs of hydraulic cylinders (36), (37) and (38), (39) being articulated to one another.