Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/12—Accessories for subsequent treating or working cast stock in situ
  • B22D11/126—Accessories for subsequent treating or working cast stock in situ for cutting
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/12—Accessories for subsequent treating or working cast stock in situ
  • B22D11/126—Accessories for subsequent treating or working cast stock in situ for cutting
  • B22D11/1265—Accessories for subsequent treating or working cast stock in situ for cutting having auxiliary devices for deburring

Definitions

• the present invention relates to a device for deburring steel slabs, or similar flat metal products, intended for removing existing burrs on the ends of the slabs, in particular before they are rolled.
• a conventional method of manufacturing flat steel products is to continuously pour liquid steel into continuous casting molds. At the outlet of the casting installation, the steel strip which is still hot is cut into pieces of variable length as required, called slabs.
• This cutting is conventionally carried out on the fly, that is to say when the said strip passes, perpendicular to the direction of travel, and using oxy-cutting torches.
• This cutting causes oxycutting burrs on the two ends, called respectively head and tail, of the slab thus cut, these burrs being particularly important on the underside, that is to say on the side where the flame of the torch opens.
• These burrs which extend over the entire width of the slab, typically have a width of 20 to 50 mm and a thickness of 10 to 15 mm.
• burrs due to oxycutting, the metal constituting these burrs has a different chemical composition and mechanical characteristics from the steel of the slab. These burrs must therefore be removed before hot rolling to avoid any defect on the rolled product but also to avoid that the burrs damage the rolling rolls in the long run or come off randomly during rolling and accumulate in various places. of the rolling tool, with the risk of causing it to malfunction after a certain time.
• a first method consists in removing the burrs on the still hot slab, just after the cutting at the end of the continuous casting, by slicing by cutting discs or by hammering, but it is then necessary as much deburring equipment as lines continuous casting.
• document FR-A-2 553 318 describes a deburring machine comprising a double-edged blade mounted on an oscillating arm and extending transversely to the longitudinal direction of the slab.
• the swinging arm can move between two neighboring rollers of a roller path for transporting the slab, around an axis of oscillation oriented parallel to the axes of the rollers, and therefore parallel to the edge of the slab to be deburred.
• a pivoting of the latter in the direction of the advance of the slab makes it possible to remove the burr at the head of the slab, by a cutting edge of the moving blade substantially tangentially to the bottom surface of the slab.
• a blade holder oriented parallel to the edge of the slab to be deburred carries several knives oriented transversely to this edge. After having made these knives penetrate the burr to the lower surface of the slab, the blade holder is moved parallel to said edge, each knife removing part of the burr over a length equal to the displacement of the blade holder.
• Such devices make it possible to avoid positioning the slab as precisely as in the system described above. By cons, they require means of vertical displacement of the blade holder and the use of movable stops s' applying on the upper face of the slab to prevent its lifting when the knives enter the burr.
• the present invention aims to solve these various problems and aims in particular to ensure effective deburring, making it possible to remove practically all of the burrs. It also aims to completely remove these burrs without however risking injuring the slab by the knives. It also aims to provide a device of simple design, compact, and not requiring control means or actuators consuming electrical energy. It also aims to provide a device having a reduced cost both in terms of investment and maintenance. Finally, it aims to reduce the number of deburring devices required in a production installation grouping continuous casting and rolling installations, and to eliminate the passage of slabs by an additional work station between casting and rolling.
• the present invention relates to a slab deburring device comprising at least one blade extending transversely to a direction of movement of the slab and movable in this direction, substantially tangentially to the lower surface of the slab, characterized in that it comprises a movable feeler which can be placed on the trajectory of the slab so as to be actuated by a front end face before the slab during the displacement of the latter, and displacement means blades for moving said blades from a position upstream of the probe in the direction of movement of the slab and at a speed greater than that of the slab, when the slab comes into contact with said probe and moves it this.
• the device according to the invention makes it possible to remove the burr from the front face situated towards the front of the slab relative to its direction of movement, during the movement of the latter, and therefore without it being necessary. to immobilize or position it.
• the device according to the invention uses the kinetic energy of the slab in movement to drive the blades and carry out deburring on the fly during said movement.
• the device is placed at the outlet of the reheating furnace, on a table for feeding the slabs to a roughing stand of the hot rolling mill.
• This location makes it possible to use a single device for all the slabs which must be rolled on the hot train and, by ensuring deburring on the fly on the normal slab path between the reheating furnace and the roughener, avoids transport additional slabs that would be necessary to pass them through an independent deburring station. Furthermore, deburring is carried out automatically, and therefore with certainty, before any rolling operation.
• the high temperature of the slab leaving the reheating oven typically from 1100 to 1250 ° C., facilitates the removal of the burr, because at this temperature the attachment of the burr to the slab is relatively fragile, the the energy required to remove the burr is reduced, and the mechanical stress on the various elements of the device is low.
• the flatness of the slabs is better, because at this location, they are not bent as can be hot slabs stacked before loading.
• the blade displacement means comprise pivoting blade arms around a first fixed axis perpendicular to the direction of movement, said first axis being located in an area located substantially perpendicular to the probe in said waiting position , and the probe is mounted on probe arms pivoting around a second fixed axis parallel to the first axis, the probe arms being connected to the blade-holder arms by connecting rods, in a configuration such that a displacement of the probe in the direction of movement of the slab causes a displacement of the blades in the same direction and with an amplitude greater than that of said movement of the probe.
• the arm and link system constitutes a speed amplifier thanks to which the blades, the displacement of which is caused by the displacement of the probe, itself pushed by the slab, are driven faster than the slab itself.
• Said distance is determined so that the blades can grasp all the burrs, and can for example be typically of the order of 10 cm, which is generally sufficient to be able to remove all forms of burrs while not flush with the slab over a short length, thus avoiding any risk of marking its lower surface over a longer length.
• the blades are mounted on a pivoting arm whose axis is substantially perpendicular to the face before the slab during deburring, the blades are found, after the removal of the burrs, cleared sufficiently below the underside of the slab, thus eliminating any risk of marking the slab when it continues to move at - above the device.
• the device comprises return means which may be constituted simply by a counterweight or preferably, in addition to or in place of the counterweight, by a jack acting for example on a rod linked in rotation to the blade arms.
• This cylinder for example a pneumatic cylinder, is controlled to return the device to its standby position after the slab has passed completely over the deburring device, for example simultaneously with the command to feed the next slab.
• This cylinder put in free or controlled exhaust as soon as the device has been returned to its standby position, can also serve as a shock absorber during deburring, to avoid too rapid pivoting of the blade-holder arms, due to impact upon arrival of the slab in contact with the probe.
• the blade movement control is completely mechanical, the position of the blades relative to the front face of the slab during deburring being determined by the geometry of the system, in particular by the relative positioning of the axes of the arms blade holders and probe arms, and the length of these and connecting rods.
• the detection accuracy of the position of the face to be deburred is therefore guaranteed and there can therefore be no drift or disturbance which would be due to means of position detection separate from the deburring tools.
• the relative speed of the blades relative to the slab can remain sufficiently low, depending solely on the geometry of the system, for example of the order of 20% of the speed of the slab, which ensures smooth deburring, without shock liable to damage the cutting edge of the blades.
• the estimated service life of the blades can reach two years, i.e. around 250,000 deburring. Furthermore, the mechanism is of low inertia and only creates a soft impact of the slab on the feeler when it comes into contact, which ensures reduced stresses on the various organs of the device and therefore a greater longevity and reduced maintenance.
• the blades are mounted on one end of blade-holder links articulated by their other end on an upper end of the blade-holder arms and connected moreover to said blade-holder arms by means of elastically deformable connections, these means comprising for example a connecting rod provided with a compression spring acting to move the blades away from the first articulation axis and with an adjustable stop to limit the pivoting of the blade-holder links.
• these means comprising for example a connecting rod provided with a compression spring acting to move the blades away from the first articulation axis and with an adjustable stop to limit the pivoting of the blade-holder links.
• the device comprises several blade-holder links articulated independently of one another on said blade-holder arms and each of said blade-holder links having its own elastic connection means with said blade-holder arms. All the blades thus arranged side by side in the direction of the width of the slab, can thus perfectly match the lower surface of the slab over the entire width thereof, despite the possible flatness defects of the slab, each blade-holder rod pivoting more or less, thanks to the elastic deformation of the said connecting means, as a function of the exact position in height of the zone of the slab located directly above each blade .
• the simplicity of operation of the mechanism is also noted, which is a guarantee of reliability, any malfunction which can moreover be quickly detected, in particular because the location of the device on the normal course of the slab before the roughener makes it easily visible and accessible by the personnel supervising the rolling mill, as well as a purely mechanical construction and inexpensive compared to the devices according to the prior art.
• FIG. 1 to 3 schematically represent the principle of the device, in the three successive phases of waiting, deburring, and clearing after deburring
• - Figures 4 to 6 represent, in the same three phases, an embodiment preferential of the device
• FIG. 7 shows the means for returning the device to the standby position
• FIG. 8 is a simplified representation of the device in the deburring position, in front view according to arrow F in FIG. 5.
• a slab 1 is shown diagrammatically, the front face 2 of which, commonly called the slab head, has a burr oxycutting 3, extending from this front face downwards, below the lower face 4 of the slab.
• Slab 1 is moving in the direction of arrow FI on a conventional roller table.
• the deburring device 5, arranged between two rollers 6 of this table, has been shown diagrammatically therein to facilitate understanding of its operation during deburring.
• the deburring device comprises blades 11 mounted on an upper end of a blade-carrying arm 12 articulated around a first horizontal axis A and perpendicular to the direction of movement of the slab, and therefore parallel to the axes of the rollers 6 It also comprises a probe 13 carried by an upper end of a probe arm 14 articulated around a second axis B parallel to the first axis A.
• the blades 11 are mounted articulated around an axis C on the support arm blade 12, and a compression spring 16 is placed between said blades and the arm 12.
• the lower ends of the arms 12 and 14, respectively opposite the blades and the probe relative to their axes of articulation, are connected by a connecting rod 15.
• the position of the axes A and B as well as the dimensions of the arms 12 and 14 are such that, in the standby position shown in FIG. 1, the probe 13 is located above the rolling plane PR of the roller table, in the trajectory of the slab 1 and opposite its front surface 2. In this standby position, the blades 11 are located below this plane PR, the cutting edge 111 of the blades being moreover located upstream of the feeler FI of slab displacement.
• the distance between the plane PR and the axis A of articulation of the blade support arm 12 is slightly less than the distance between said axis A and the cutting edge 111 of the blades.
• the cutting edge 111 of the blades 11 can follow the rectilinear movement of the slab by virtue of the articulation of the blades on the blade-carrying arm, around the axis C, and by virtue of the springs 16 which compress from the moment of the cutting edge coming into contact with the lower face 4, allowing the blades to pivot down while keeping their cutting edge 111 pressed against the slab.
• the device is shown in a position in which the cutting edge 11 of the blades has joined the front face 2 of the slab, after removing the burr 3. It will be noted that in this position, the cutting edge 111 of the blades s' is close to the probe 13, since the blades have moved faster than the said probe.
• the slab continued its movement while continuing to push back the probe 13.
• the probe arm 14 continued its pivoting around the axis B, likewise causing the blade-holder arm 12 to pivot with a greater angle to that performed by the probe arm.
• the probe is found below the plane PR, as are the blades 11, and thus authorizes the continuation of the movement of the slab, without interfering with it.
• the speed increase of the blades 11 relative to the probe 13 is caused by the particular arrangement of the axes A and B and by the length of the arms 12 and 14.
• the axis A is located at a level in below axis B, the length of the arms respectively between the blades and axis A on the one hand and the probe and axis B on the other hand, being substantially equal.
• the AT / AE ratio is greater than the BP / BD ratio.
• FIGS. 4 to 8 After having explained the principle of the kinematics of the device according to the invention, a description will now be given in relation to FIGS. 4 to 8 of a practical embodiment of this device, used for deburring slab heads, and arranged on the slab routing table between the outlet of a reheating furnace and a roughing cage of a belt train.
• the device is placed between two rollers 6 of the roller table.
• the probe 13 is constituted by a central boss of a beam 17 extending transversely to the roller table and having a length greater than the width of the slabs 1 to be deburred.
• the beam 17 is fixed at its ends to the upper ends of the probe arms 14, which are pivotally mounted about the axis B by means of pins 18, integral with the probe arms 14 and guided in bearings 19 of a frame fixed 20, shown only partially.
• the device comprises a plurality of blades 11 juxtaposed transversely to the direction of movement of the slab 1, with minimal functional clearance between two adjacent blades, so as to be able to act over the entire length of the burr 3.
• Each blade is mounted on blade-holder links 21 pivotally mounted around of the axis C on the upper end of the blade-holder arms 12.
• Each blade-holder arm 12 consists of two flanges 22 welded to a ring 23, and all the arms 12 are joined together in rotation, for example by keying of the rings 23 on a main shaft 24 of axis A.
• the main shaft is journalled at its two ends in bearings of the frame 20, the assembly of the blade-holder arms being entirely located between the two probe arms 14
• Two of the flanges 22, for example the flanges 22 ′, located inwards, of the blade-carrying arms located most outwards, extend on the side opposite to the blades and carry a counterweight 25.
• the other flanges 22 "of these arms have an extension 26 also extending opposite the blades and carrying a pin 27 of axis E.
• a link 15 connects a lower end 28 of the feeler arms 14 to said extension 26 while being articulated with on the one hand on said end 28 by an articulation 29 of axis D and on the other hand on the pin 27.
• the pin 27 is pivotally mounted on a yoke 30 sliding on the link 15 and adjustable in position by a system 31 with screw and nut.
• Each blade-holder arm 12 has tabs 32 extending substantially perpendicular to the arm 12 and on which is pivotally mounted a ring 33 crossed by a threaded rod 34 carrying a yoke 35 articulated on the blade-holder link 21, at a distance from the 'axis C.
• a compression spring 16 is placed around the threaded rod 34, between the ring 33 and a thrust washer 36, and tends to pivot the blade holder rod 97/36705 PC ⁇ 7FR97 / 00482
• a nut 37 screwed onto the rod 34 and abutting on the ring 33 on the other side of the spring 16, limits the pivoting of the connecting rod blade 21 and allows the blade 11 position to be adjusted.
• the articulation system of the blade-carrying links 21 on the blade-carrying arms 12, in combination with the elastic thrust system of these links not only makes it possible to transform the circular movement of the blade-carrying arms into a movement straight edges of the blades, allowing to follow precisely tangentially the lower surface of the slab during its movement for the duration of deburring, but it also makes it possible to automatically adapt the position of the blades to the geometry of the slab.
• the higher the number of blades that can pivot independently of each other the more the device will be able to adapt to the shape, hollow or curved, of the underside of the slab, and therefore to perform optimal deburring over the entire width of the slab.
• four blades and blade holders mounted on the same shaft constitute a good compromise, for a total width of the order of 2000 mm, between too great a complexity of the device and satisfactory efficiency.
• the return to the standby position can be effected only by the counterweight 25, then having sufficient mass for this end, and a rotary roller can then be provided on the probe arms or on the beam to avoid contact of the probe with the underside of the slab during its movement after deburring, as long as the slab is above the device.
• the acceleration of the blades relative to the slab head can be obtained other than by the mechanical speed amplification system using the arm and link system described above.
• the blade-carrying arm may be mechanically armed in the standby position, that is to say subject to a certain stress, for example by a pressurized jack or springs and kept under this stress by a linked locking member. to the probe, and the release of this constraint being effected when the slab head approaches the probe and moves the said locking member.
• the thrust force provided by the jack or spring must be sufficient to accelerate the blades so that they manage to catch up with the slab head over a short distance.
• the device described above is particularly intended for deburring the heads of slabs in the process, during their direct movement from the reheating furnace to the roughener.
• a similar device could also be used for deburring the slabs of the slab, that is to say to remove the burr formed on the rear end of the slab considered in its direction of movement towards the rougher, by means of placing this device in opposite direction and to consent to a return back of the slab after it has passed over the device.
• this way of doing things would be penalizing both in terms of space required and in time to deburr the two ends of the slab.
• another device will be used which is particularly suitable for deburring the slab tail, such as that described in the French patent application in the name of the applicant of the present application and filed on the same day as the latter, on which can refer.
• the head deburring device and the tail deburring device may be placed close enough to each other on the slab transport path, so that during the slowdown caused by deburring from the head, the tail is located near the tail deburring device. This assumes that, in the direction of travel of the slab towards the rougher, the head deburring device is after that of the tail deburring, so that the two operations are take place almost simultaneously.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Milling, Broaching, Filing, Reaming, And Others (AREA)
• Milling Processes (AREA)
• Metal Rolling (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=9490834

Family Applications (1)

Country Status (8)

Family Cites Families (1)

• 1996
  • 1996-03-29 FR FR9604138A patent/FR2746684B1/fr not_active Expired - Fee Related
• 1997
  • 1997-03-19 JP JP9534964A patent/JP2000507506A/ja active Pending
  • 1997-03-19 AU AU22965/97A patent/AU2296597A/en not_active Abandoned
  • 1997-03-19 EP EP97915515A patent/EP0889764A1/de not_active Ceased
  • 1997-03-19 KR KR1019980707690A patent/KR20000005063A/ko not_active Withdrawn
  • 1997-03-19 WO PCT/FR1997/000482 patent/WO1997036705A1/fr not_active Ceased
  • 1997-03-19 BR BR9708384A patent/BR9708384A/pt not_active Application Discontinuation
  • 1997-03-19 CA CA002250762A patent/CA2250762A1/fr not_active Abandoned

Non-Patent Citations (1)

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