Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D5/00—Bending sheet metal along straight lines, e.g. to form simple curves
  • B21D5/06—Bending sheet metal along straight lines, e.g. to form simple curves by drawing procedure making use of dies or forming-rollers, e.g. making profiles
  • B21D5/10—Bending sheet metal along straight lines, e.g. to form simple curves by drawing procedure making use of dies or forming-rollers, e.g. making profiles for making tubes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
  • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
  • B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
  • B21C37/08—Making tubes with welded or soldered seams
  • B21C37/0815—Making tubes with welded or soldered seams without continuous longitudinal movement of the sheet during the bending operation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
  • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
  • B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
  • B21C37/08—Making tubes with welded or soldered seams
  • B21C37/0822—Guiding or aligning the edges of the bent sheet
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D5/00—Bending sheet metal along straight lines, e.g. to form simple curves
  • B21D5/01—Bending sheet metal along straight lines, e.g. to form simple curves between rams and anvils or abutments
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D5/00—Bending sheet metal along straight lines, e.g. to form simple curves
  • B21D5/01—Bending sheet metal along straight lines, e.g. to form simple curves between rams and anvils or abutments
  • B21D5/015—Bending sheet metal along straight lines, e.g. to form simple curves between rams and anvils or abutments for making tubes

Definitions

• the invention relates to a method for producing slotted tubes from metal sheets, in particular thick metal sheets, wherein a metal sheet is one
• Tube form press is supplied, in which it is formed on a lower tool lying on a lifting and lowering upper tool by applying a bending force progressively to the laterally welded slot tube having a gap opposite longitudinal edges. Furthermore, the invention relates to a device for performing the method.
• a tube forming or tube bending press usually has in a base frame a lower tool consisting of two supporting or bending bodies arranged next to one another at a lateral spacing, and a vertical tool that can be adjusted against the lower tool from above and is supported over the entire length by a lifting and lowering bending bar the metal sheet extending upper tool with which a bending force can be applied to the metal sheet resting on the lower tool.
• the metal sheet is pre-bent on the longitudinal edges, usually in a separate edge bending press.
• the longitudinal edges are pre-bent so that the tube radius is evenly shaped when it is deformed into a slotted tube in the area of the subsequent seam, where the longitudinal edges of the sheet metal sheet bent over to the tube lie opposite one another for longitudinal seam welding with a gap.
• the sheet metal sheet pre-bent in this way is then pushed into the tube molding press and subjected to the actual bending process there.
• a very problematic in the advancing molding process has been a large residual gap of the slot of about 130 to 170 mm, which is significantly influenced by the width of the blade, particularly in the case of thick-walled tubes of, for example, 40 mm, and also stresses in the slot tube.
• a large slot width requires high closing forces in the braze welder, and because of the high tensions in the tacked as well as residual tensions in the finished welded tube, there is a risk of a tearing tack or weld seam. If slot widths that are too large are detected, remedial measures are taken to ensure that experienced machine operators have closed the slot as far as possible by repeatedly operating the tube forming press manually.
• a lower tool designed with reversible means in its direction of rotation and a stamp which can be acted upon from outside against the positioned preform are provided for forming the sheet metal sheet into a non-circular preform and then forming it into the slotted tube.
• Slotted pipes sometimes have larger or smaller radii, which is noticeable in different slot widths.
• the radii can also be of different sizes on the left and right, which is problematic in that optimal operation of the closing press requires modified parameters both from tube to tube and from left to right.
• the invention is therefore based on the object of creating a method and a system of the type mentioned at the outset without the disadvantages mentioned, in particular also in the case of thick-walled and small-diameter tubes, for example about 800 mm, to produce circular-cylindrical slotted tubes with reproducible quality create.
• Two bending steps or two squeezing processes can be sufficient both for area-wise non-circular preforming and for the final or finished molding, even in the final shaping with the squeezing force applied to the left and right of the gap or slot.
• individual turning and pressing parameters are determined for each individual tube and for the two sides of the sheet metal to be molded.
• the individual contour should be determined in order to determine tailored parameters for slot tube positioning, in particular the angle of rotation or the turning length, based on the respective current tube position using a corresponding geometry model for the right and left side of the slot tube.
• measuring devices for determining the current geometry are required, which can preferably be arranged in the form of measuring robots at the pipe end in the closing presses.
• the control is intended to provide real-time output of the values calculated for displacement and pressure in order to implement a stroke control that is dependent on the yield point.
• an even number of steps is selected in the molding press, so that the closing can possibly only be carried out by a single pressing step.
• the first side should be manufactured with reduced immersion depths in order to achieve out-of-roundness, but the second side is then preferably molded in like a conventional tube, in particular a round tube.
• the end gap should preferably not be chosen too small in order to avoid undesired contact between the shaping sword and the support tube section.
• an asymmetrical preform with an even number of steps can also be produced in the JCO molding press, which previously could only be done with odd forming steps.
• the last forming step is no longer in the middle of the slotted tube and a collision between the edges of the slotted tube and the shaping sword can be prevented.
• the advantage of the invention is that in the closing process, each individual tube can be reacted to individually, ie that tailor-made rotations and Press strokes are carried out in order to achieve the most uniform possible result when the sheet metal is formed into a slotted tube.
• As a result better quality is achieved overall, since slotted tubes enter the tack welding machine with a more uniform shape and correspondingly more uniform tubes are produced in the tacking process. Differences in the slotted tube contour, which could occur when using rigid machine parameters, are minimized as far as possible.
• An advantageous measure according to the invention provides that the non-round preform is positioned in the finishing step before the application of the compressive force by rotating clockwise or counterclockwise. Depending on the positioning, the compressive force is thus introduced into the non-round preform to the left or right of the slot or gap.
• the area which is less molded to the right of the center is rotated to an approximately 3 o'clock position and the area which is molded less to the left of the center to an approximately 9 o'clock position.
• the object underlying the invention is achieved with a device in that means for measuring the current geometry of the molded-in
• Sheet metal are provided, which with a device for control
• a lower tool which is designed with reversible means in its direction of rotation, and a punch which can be acted upon from the outside against the positioned preform is preferably provided.
• the finished slotted tube can thus be produced starting from the sheet metal on a single tube form press or machine.
• the reversal of the direction of rotation allows the non-circular preform to be positioned exactly so that the pushing force comes into effect at the location of the action, namely on both sides of the slot.
• the bending bar of the tubular molding press can also be used to apply the compressive force from the outside to the preform.
• the press can be converted with an additional stamp.
• a preferred embodiment of the invention to increase the production output provides that at least one tube forming press producing a non-round preform is followed by a squeezing press which has the lower tool designed with reversible means of rotation and, as the upper tool, the punch which can be acted upon from the outside against the positioned non-round preform ,
• the tube forming press from which the non-round shape is ejected, is followed by a squeezing press, in which the non-circular preform supplied is formed into the finished slot tube in at least two successive steps, in each case to the right and left of the slot or gap ,
• the non-circular preforming of the metal sheet can thus be carried out at a location that is independent of the final deformation to the slotted tube.
• the rotatable means of the lower tool are designed as two rotatably driven rollers arranged at a distance from one another.
• the reversal of the direction of rotation of the rollers allows the non-round preform to be positioned for the final shaping with optimized force application.
• the course of time on the one hand in the preforming in the tubular molding press and on the other hand in the completion in the squeezing press allows a downstream squeezing press to operate two tubular molding presses.
• An embodiment of the invention provides that the rotatable rollers are mounted with a suspension.
• the support of the non-circular preform on the lower tool of the compression press can be improved by a stationary support body provided between the rollers.
• Fig. 1 shows schematically the manufacture of a slotted tube according to the
• Fig. 2 as a detail of Figure 1, the squeeze press with the non-circular preform introduced into it. 3A, 3B, the reforming or reshaping of the non-circular preform from the
• Pipe shape press in at least two stages of the Press-in, in a first bending step by applying force to the non-round preform to the right of the slot or gap (FIG. 3A) and after rotating the non-round preform in a second bending step by applying force to the left of the slot or gap (FIG. 3B), represented schematically; and
• 4A, 4B schematically show two alternatives for producing an asymmetrical preform by means of a method according to the invention, which uses an even number of steps in the forming steps.
• the non-circular preform 13 thus produced in a first stage in the tube forming press 1 is, after being conveyed out or pushed out of the tube forming press 1, fed to a pressing press 14 connected in the production process, as shown in FIG. 2b.
• the squeeze press 14 has a lower tool 15 which consists of two rollers 16a, 16b, which are provided at a distance from one another and are reversible in their direction of rotation, as indicated by the double arrows in FIG. 2b, and a stationary roller bridging the distance between the rollers 16a, 16b Support body 17 exists.
• the rotatable rollers 16a, 16b can be supported by a spring means 18 (cf. FIG. 3).
• the lower tool 15 An upper tool 20 formed with a stamp 19 is arranged opposite.
• the pressing force for producing the finished, largely circular slotted tube 104 is applied to the non-circular preform 13 from the outside via the stamp 19.
• the non-round preform 13 is positioned via the rotatable rollers 16a, 16b in such a way that the less molded area 12b to the right of the slot or gap 11 is in a 3 o'clock position, as in FIG. 3 by the dot-dash line , horizontal line indicated
• the second squeeze-bend step is illustrated in Fig. 3B in the same order as before.
• the preform 13 which is here non-circular in its left half, has been positioned in such a way that the area 12a less molded to the left of the slot or gap 11 assumes a 9 o'clock position.
• the pressing force F (middle figure) now applied by the stamp 19 on this side of the preform 13 then brings the non-round preform 13 into the final, largely circular shape of the finished slotted tube 104 with the significantly smaller slit or gap 111 achieved thereby (Fig right outside).
• FIGS. 4A and 4B show the production of asymmetrical preforms with an even number of steps (FIG. 4B) or an odd number of steps (FIG. 4A).
• a so-called potato shape is introduced onto the metal sheet 3 by means of the bending sword 7, a so-called potato shape on the side A and a round half-shape on the side B in the metal sheet 3. While the so-called potato shape on side A does not collide with the sheet metal plate 3 and the bending bar 7 causes, the sheet metal plate 3 abuts the bending bar 7 on side B, into which a substantially round shape has been introduced into the sheet metal plate 3.
• FIG. 4A with 21 steps, ie 21 forming processes, a so-called potato shape is introduced onto the metal sheet 3 by means of the bending sword 7, a so-called potato shape on the side A and a round half-shape on the side B in the metal sheet 3. While the so-called potato shape on side A does not collide with the sheet metal plate 3 and the bending bar
• 4B illustrates the advantage of having an asymmetrical preform with 20 steps, ie an even number of steps.
• side A in which a so-called potato shape was introduced into sheet metal 3, nor in side B, which was formed into a substantially round preform by means of shaping sword 7, does sheet metal 3 collide with shaping sword 7, because the last forming step along the dash-dotted line 21, thus laterally offset to the center of the tube, takes place.
• the last forming step is no longer in the middle of the slotted tube 4 and a collision between the edges of the slotted tube 4 and the sword 7 can be prevented.

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• 2018
  • 2018-07-09 DE DE102018211311.4A patent/DE102018211311B4/de active Active
• 2019
  • 2019-07-05 RU RU2019121067A patent/RU2729480C1/ru active
  • 2019-07-09 JP JP2021500293A patent/JP7185007B2/ja active Active
  • 2019-07-09 WO PCT/EP2019/068370 patent/WO2020011772A1/de unknown
  • 2019-07-09 EP EP19739552.8A patent/EP3820631A1/de active Pending
  • 2019-07-09 KR KR1020207037621A patent/KR102506358B1/ko active IP Right Grant
  • 2019-07-09 CN CN201980046232.1A patent/CN112399894B/zh active Active

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