Classifications

• • 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
  • B21C37/15—Making tubes of special shape; Making tube fittings
  • B21C37/154—Making multi-wall 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
• • 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
  • B21C37/09—Making tubes with welded or soldered seams of coated strip material ; Making multi-wall tubes
• • 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
• • 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
  • B21D5/12—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 making use of forming-rollers

Definitions

• the present invention relates to a production-optimized method for producing a multilayer pipe.
• Multilayer pipes are preferably used in case of high requirements against corrosion or abrasion.
• Corrosion-resistant pressure vessels or pressure lines can be produced more cost-effectively by using multilayer pipes than solid versions made of appropriate materials. This is achieved by the load sharing on a thin, corrosion resistant inner layer (e.g., stainless and acid resistant steel) and a high strength, pressure resistant outer layer (e.g., fine grain structural steel). As a result, overall steel consumption can be significantly reduced and much of the remaining steel consumption can be shifted to low-cost materials.
• a thin, corrosion resistant inner layer e.g., stainless and acid resistant steel
• a high strength, pressure resistant outer layer e.g., fine grain structural steel
• Abrasion-resistant pipes are made possible by the design as a multilayer pipe (such as mechanical bond, see below) in certain grades in the first place, because materials (eg high-strength steels with high hardness) can be used as an inner layer, which alone or only very difficult can be processed into tubes.
• steel sheets - is used as a starting semi-finished a clad composite sheet of two different (steel) materials use.
• the inner tube is pressed with elastic expansion of the outer tube into the outer tube. After elimination of the expansion forces, the outer tube sets because of the higher elastic resilience frictionally around the inner tube.
• the multilayer material thus formed is formed into a multilayer pipe with the aid of the bending roll, wherein in the final phase of pipe forming in the bending roll, a respective material layer functioning as an inner pipe is pressed non-positively into a material layer acting as an outer pipe.
• the use of rolled and / or blast-plated semifinished product is avoided by first creating a first joint between the layers of material, such as a weld, and thereafter the respective layer of material acting as an inner tube during tube forming in the bending roll by attaching it after a certain deformation progress - Pressed further connection between the material layers frictionally in each functioning as an outer tube material layer and is frictionally held in the respective outer tube and without having to expand the multilayer tube and thus to address the above-mentioned expansion method disadvantages. Nevertheless, this method has the technical production disadvantage that it is necessary to create a further connection between the material layers during the tube forming in the bending roll after a certain deformation progress, which is usually done by welding.
• the still unfinished pipe must be removed from the bending roll and then created the connection, so in general, the weld can be applied.
• it can also be welded in the bending roll, which however blocks it during this time.
• the tube blank also called slot tube
• Such a procedure is extremely time-consuming and therefore represents a significant production cost disadvantage.
• WO 2006/066814 Al also teaches a method in the
• a material layer acting as a respective outer tube forms a base plate, which has a stop edge preferably approximately along its two longitudinal edges or approximately parallel thereto, and the resting material layer lies loosely between these stop edges comes, and
• the multilayer material thus formed is formed with the aid of the bending roll to form a multilayer pipe, wherein the respective material layer functioning as an inner tube is clamped between the abutment edges and in the final phase of tube forming in the bending roll the respective material layer functioning as inner tube thereby frictionally locking into the respective outer tube Material layer is pressed.
• the respective inner layer it is thus also possible to use those materials, such as particularly high-strength steels, which are difficult or impossible to weld.
• the material layer acting as an inner tube is already pressed into the bending roll in the bending roll in a force-fitting manner into the respective material layer functioning as an outer tube and thus held frictionally in the respective outer tube, without a connection, such as a weld to be created. suture needs. Therefore, a time- and cost-intensive interruption of the tube forming process in the bending roll is also not required here.
• this manufacturing process in turn has the disadvantage that in this case the pipe inner layer is not completely closed inwardly, since a part of the pipe inner circumference is formed by the on the respective base plate, so the respective outer material layer, attached stop edges, which leads to here the beneficial effects of the tube inner layer, such as corrosion or abrasion resistance can not occur.
• This disadvantage can not be solved simply by a build-up welding in this area, as a weld between the material of the stop edge and the inner layer in this process, which wants to avoid welding between outer and inner layer just not i ⁇ frage comes.
• This object is achieved by a method for producing a multilayer pipe using a Blechumformmachine in which
• the multilayer material formed in this way is formed into a tube, and during the deformation, the edges of the elements of the resting factory sheet still freely displaceable relative to one another move freely towards each other due to the different circumferential lengths of inner tube and outer tube according to the deformation progress. then these mutually moving edges of the elements of the overlying material layer abut each other after a certain deformation progress, and
• the multi-layer pipe is formed with the help of Blechumformmaschine to the end, which now can not move freely towards each other during this final molding, the edges of the elements of the overlying material layer, whereby the respective acting as an inner tube material layer non-positively pressed into each acting as an outer tube material layer becomes.
• the interruption of the tube forming process in the sheet metal forming machine - ie in the bending roll - thereby avoided that at least two elements that later form the inner layer, initially, ie before the tube forming process, edge side with the later forming the outer layer Material layer connected, so usually welded to this, be.
• the free ends of these elements then move towards each other due to the different bending radii (or circumferential lengths, which means the same) of the inner and outer tubes and eventually hit one another.
• the edges of the abutting layers do not jump from each other, but remain abutting, but they - assuming a smooth edge shaped - a, with increasing deformation progress increasing strength exert on the material inner layer, with which this is pressed against the outer layer.
• the method according to the invention is designed so that it ensures that from the moment in which the initially still freely mutually displaceable edges of the inner layer sheets abut, the tube to be formed at each point, on the inner and outer layer on each other, already arched. That is, the tube to be formed at each point, on the inner and outer layer on each other has a finite radius (ie nowhere there has an infinite radius).
• This can be achieved, for example with respect to the majority of the tubular body, preferably by sufficient bending before abutting the displaceable edges of the inner layer elements, which can be done for example by suitable dimensioning and / or positioning of the elements of the inner layer. Also, this (possibly also in addition) - preferably in the edge region, so the area of the later to be closed pipe longitudinal seam comes close - means a previously made bending of the pipe to be formed material layers can be achieved.
• the method for producing a multi-layer pipe according to the present invention is characterized in that the first connection between the material layers is provided by approximately along one of the longitudinal or transverse edges of the overlying material layer or approximately along a line parallel thereto but along the future pipe joint seam are connected to each other.
• the applied elements can thus lie with their longitudinal edge parallel to the longitudinal edge of the underlying material layer, but need not. So it is also possible that they come to rest with their longitudinal edge transverse thereto.
• the connection with the material layer below is always along or parallel to the future pipe longitudinal seam.
• connection along an edge or along a (preferably imaginary) line means any type of connection along the edge or line, whether or not it is Connection along the entire edge or line or only in sections along the edge or line or even in single points (such as spot welds), for instance at two points - preferably at the end points of the edge or line - or even at a single point at the point Edge or on the line.
• the material layer functioning as an inner tube can also form a partial circle in the finished multilayer tube, which can be achieved by covering the elements of the overlying material layer, which later form the inner tube layer, only a part of the surface of the material layer which later forms the outer layer. while it is nevertheless important to ensure that they still encounter each other in the course of the tube forming process with their then free ends and so the inner is pressed into the outer layer.
• the material layer functioning as an inner tube and forming a partial circle in cross-section in the finished multilayer tube forms a groove at the foot of the multilayer tube.
• a further connection preferably welding between the material layers and / or the abutting edges of the elements of the overlying material layer done, in particular here this jaw tightly shut down.
• An interruption of the actual molding process is not required for this purpose. Rather, such a step takes place only after completion of the actual tube forming process.
• Al ratios are - depending on the desired pressing force - the size of the elements of the overlying material layer (ie the later inner layer) and the position of the first connections between the elements of the overlying material layer and the adjacent material layer (ie the material layer, which usually forms the outer layer later).
• the length of the neutral fiber of the outer tube - here L 1 , called - is:
• L ⁇ (DA - SA) - ⁇
• L ⁇ (DA - SA) - ⁇
• F - The deformation progress - here called F - called, in which the free sheet edges of the elements of the resting material layer to abut - so you want to reach a maximum pressing force - is then (as value between 0 and 1) about:
• DA as the outer diameter of the outer tube in mm
• SA as the wall thickness of the outer tube in mm
• IO IO
• the compression allowance takes into account the manufacturing inaccuracy in the fixation of at least one other material layer connection, and compensates for this so that the desired pressing force of the inner tube is at least achieved against the outer tube.
• the resting elements along first weld the longitudinal edges of the later forming the outer layer material layer and select these (the later inner layer forming) elements of their size and geometry forth so that between their free edges a gap remains, which closes in the course of the tube forming process and then the two then abutting Edges are encountered by the yet to be completed further tube forming process only insofar as it allows the compression limit of the material of the future inner layer.
• the multilayer pipe is closed by welding the outer pipe along the pipe seam and build-up welding of the inner pipe so as to complete the multilayer pipe body.
• the material layers can be connected to the front sides of the tube, such as there to prevent the ingress of moisture between the metallurgically yes not fully connected material layers.
• a preferred application of the method according to the present invention is the production of double-layer tubes according to the invention, however, the invention is not limited thereto, also three-, four- and more multi-layer pipes according to the invention are hereby basically produced.
• sheets preferably metal sheets and more preferably steel sheets, as a material layer or elements of the material layer use.
• At least one of the joints of the material layers is preferably used as a weld, which is particularly suitable for the aforementioned metal sheets, preferably steel sheets.
• Blechumformmaschine is about a bending roll, ie, for example, a three-roll bending machine, but also a press / die assembly, such as in the context of known from the prior art UOE (U-shapes, O-forms, expanding) - tube forming process (see for UOE method, for example: Hiersig, Heinz M., Encyclopedia Mechanical Engineering, Heidelberg 1997, p 704 f., To keyword "lJingsnaht-Großrohrherstellun £ c ) or the so-called JCO-Rohrverforrnungsvons is used suitable.
• UOE U-shapes, O-forms, expanding
• the pipe is formed by first placing the sheet in a press by means of a sword in the shape of a horizontal J 'and then in that of a horizontal C'. After that, it then - as in the case of the UOE procedure - is bent into the 'O'-shape'.
• the inventive method can now also be operated as a continuous production process in which the material layers to be combined or their elements (each unwound from a wound tape and then continuously superimposed, preferably continuously welded, wherein the subsequent tube forming process also takes place continuously by an Einform No, which forms a slit tube from the continuously superimposed material layers, serves as Blechumformmaschine for tube forming are known, for example from the prior art, as described in US 3,327,383 and hereby incorporated in the disclosure of the present document w ill.
• Fig. 2 is a perspective sketch outlined in a - not yet completed -Multlagen tube from one end face during the manufacturing process according to the invention, namely in the process step, where the thus formed Mehrlagen- material is formed using the Blechumformmaschine to the tube, the edges of the two resting Elements are still freely movable against each other,
• FIG. 3 is a perspective view sketched in a - also not yet finished - multilayer pipe from one end face during the manufacturing process according to the invention, namely in the process step, where after a certain deformation progress, the two free abutting edges of the overlying elements now abut each other,
• FIG. 4 shows a perspective cross section through a finished multilayer pipe with inner and outer layer
• 5 shows a perspective cross section through a multilayer pipe with inner and outer layer in a detailed view in the region of the weld
• FIG. 6 shows a continuous tube forming process according to the present invention in a schematic representation, in which the material layers to be combined or their elements are each in the form of wound-up strip (also called a coil), from which they are unwound and thereafter placed continuously over one another,
• wound-up strip also called a coil
• FIG. 8 shows the forming step which forms a 'U' by means of a press (not shown here) which drives a correspondingly shaped punch downwards, where the material layers are thereby jointly driven into a die (not shown here as well) , and
• Fig. 9 shows the forming step of an 'O', ie a slot tube ausformungt by means of a press (not shown here), which drives two shaped as a half-round punch from below and above against the tubular body to be formed, where the material layers in turn together to one - seen in cross section - round shaped.
• Fig. 1 shows a perspective sketch outlined on two superimposed to multilayer pipe material layers to be combined Ia, Ib, 2, in which case one of the material layers, namely the applied material layer Ia, Ib, which will later form the inner layer of the multi-layer tube, launched from two in the tube longitudinal direction
• Elements Ia, Ib - preferably sheets - is made, which at the beginning of the process according to the invention along its longitudinal edges 3a, 3b with the adjacent material layer 2, which will later form the outer layer of the tube, for the first time - preferably by a weld - are connected.
• Fig. 2 shows a perspective sketched in perspective - not yet finished - multilayer pipe 5 from one end side during the manufacturing process according to the invention, namely in the process step, where the thus formed Mehrlagen- material using the Blechumformxnaschine, such as a bending roll (The Blechumformmaschine itself , so about the bending roll, is hidden here and therefore not visible!)
• the tube 5 is formed, wherein in the deformation, the not yet connected to the adjacent material layer 2 edges 4a, 4b of the elements Ia, Ib due to the different bending radii of inner tube 1, Ia, Ib and outer tube 2 move freely against each other according to the deformation progress.
• the first connection between the two material layers 1, 1a, 1b "2 has already taken place here at the edges 3a, 3b which runs along the longitudinal edge of the forming inner tube 1, 1a, 1b and which has already been created before the tube forming process, for instance by welding were.
• this first connection 3 a and 3 b of the material layers 1, 1 a, 1 b, 2 can not shift relative to each other due to their connection to one another, but instead remain fixed relative to one another.
• the tube is already rounded in the upper area of the representation (ie in the region which runs towards the still open tube slot) and where the inner and outer layers 1, 1a, 1b, 2 also rest on one another (the radius is therefore here nowhere is infinite). This circumstance may not be so well recognized in the perspective view of FIG. 2 here, so that this clearing explanation is made here.
• Fig. 3 shows a perspective sketched in perspective - also not yet finished - multilayer pipe 5 from one end side during the manufacturing process according to the invention, namely in the process step, where after a certain deformation progress, the two free abutting edges 4a, 4b of the overlying elements Ia, Ib now come together.
• the multi-layer tube 5 can be formed using the Blechumformmaschine to the end (no longer visible), now no longer move due to the abutment of the edges 4a and 4b now against each other during this final shaping, whereby the respective inner tube functioning material layer 1, Ia, Ib is non-positively pressed into the respectively acting as an outer tube material layer 2.
• ebenfalss as already noted in Fig.
• Fig. 4 shows a perspective cross-section through a finished multilayer pipe 5 with inner layer (also called inner tube, inner tube, inner plate, etc.) 1, Ia, Ib and Outer layer (also called outer tube, outer tube, base plate, etc.) 2, wherein the multilayer tube 5 was closed by a weld 7 of the outer tube 2 along a Rorhrnaht 8 and a build-up weld 9 of the inner tube 1, Ia, Ib.
• the first connections 3a, 3b between the layers 1, 1a, 1b, 2, which already took place before the actual tube-forming process, are also indicated; Likewise, the abutting edge of the two initially free edges 4a, 4b of the two inner layer elements Ia, Ib can be seen.
• FIG. 5 shows a perspective cross section through a multilayer pipe according to FIG. 4 with inner layer 1a, 1b and outer layer 2 in a detailed view in the region of the two weld seams 3a, 3b, 7, 9.
• Fig. 6 shows a continuous tube forming according to the present invention, in which the material layers to be combined Ia, Ib, 2 or their elements in each case as a wound strip (also called coil) are present, from which they are unwound and thereafter continuously superimposed. Thereafter, then also a continuous welding of the layers at the outer edge by means of a respective welding system 10, such as a laser or a roller seam welding machine or a NOTEnahtsch Strukturmaschine or the like. Arc welding is also conceivable here.
• the subsequent tube forming process then takes place continuously again by means of an injection molding line which forms a slot tube 5 by means of contour rollers 6 from the material layers 1a, 1b, 2, which are continuously superimposed and welded together at the edge, thus serving as a sheet metal forming machine.
• the present illustration is intended to clarify the process once more, however, by showing in its upper part the installation serving for this purpose from the side and in the lower part of the illustration at different stations marked by allocation arrows 11 in cross section and, in contrast, the feed direction 12.
• the factory sheet elements Ia, Ib which are continuously fed in as a strip from above, have a width which is suitable, after carrying out the invention. According to the manufacturing process to form the desired inner wall of the pipe to be produced and also in this case to be sufficiently upset by the resulting due to the tube forming pressing force.
• the supplied from below material layer 2 is later used as an outer layer and therefore has the width of the outer circumference of the tube to be produced 5 on.
• the two layers 1 a, 1 b, 2 face each other, they are each welded at the edge by means of a welding system 10, so that the elements 1 a, 1 b of the later inner layer are now each connected to the later outer layer 2 on the outer edge.
• the two elements 1a, 1b of the later pipe inner layer still loosely lie with their edges there.
• Fig. 7 shows the initial situation of the method according to the invention, when the sheet metal forming is carried out by means of a UO (E) -Pressen- / Gesenkanaku.
• the later outer material layer 2 is down here and the two, the subsequent inner layer 1 forming elements Ia, Ib are outside. They were already welded to the lower layer 2 at the edge and there rounded together with the lower layer 2. Possibly. can the marginal welding of the layers Ia, Ib, 2 but also after the rounding of the edge area done. In the middle of the two resting elements Ia, Ib are still spaced apart.
• Fig. 8 shows the forming step of a, U 'shaped by means of a press (not shown here), which drives a correspondingly shaped punch 13 down where the material layers Ia, Ib, 2 hereby together in a die (not here also not to be seen) are driven.
• the inner material layer elements Ia, Ib with their still freely movable sheet edges - due to the different radii of outer 2 and inner layer 1, Ia, Ib - are moved towards each other.
• Fig. 9 shows the forming step, which forms an 'O', ie a slot tube by means of a press (not shown here), the two shaped as a half round punch 14, 15 drives from below and above against the tubular body to be formed, where the material layers Ia, Ib, 2 hereby again together to one - seen in cross section - are formed round.
• the inner material layer elements Ia, Ib are still moved toward each other with their still movable sheet edges due to the different radii of outer and inner layer until they abut and thus forms a continuous inner layer 1, which now in the further tube forming in the Outer layer 2 is pressed, since the originally free edges of the inner layer elements Ia, Ib can no longer move towards each other. As a result of the curvature they do not jump from each other, but lie down against the outer wall 2.
• the method according to the invention can be carried out in a similar manner by means of a press / die arrangement designed for the so-called JCO 'method.
• JCO so-called JCO 'method.
• the overlying elements 1a, 1b are welded on the edge side to the material layer 2 forming the later outer layer, and then a slot tube is formed by the JCO method.
• the desired effect according to the invention occurs, in which the initially free sheet metal edges of the inner layer elements Ia, Ib abut each other, thereby forming a continuous inner layer 1 and then pressed against the outer layer 2 due to the different bending radii of outer and inner layer.
• the initially still freely movable abutting edges of the two inner layer elements Ia Ib can be welded to one another and / or to the outer layer 2 after they abut each other , which can be done for example by the still open slot of the slot tube, preferably by means of a laser welding device.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Bending Of Plates, Rods, And Pipes (AREA)
• Rigid Pipes And Flexible Pipes (AREA)
• Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
• Metal Extraction Processes (AREA)

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• 2009
  • 2009-06-19 AT AT09776794T patent/ATE520479T1/de active
  • 2009-06-19 WO PCT/EP2009/004467 patent/WO2010145680A1/de active Application Filing
  • 2009-06-19 BR BRPI0906446-0A patent/BRPI0906446A2/pt not_active IP Right Cessation
  • 2009-06-19 EP EP09776794A patent/EP2285508B1/de not_active Not-in-force
  • 2009-06-19 CN CN2009801055969A patent/CN101983109A/zh active Pending
  • 2009-06-19 JP JP2012515359A patent/JP2012529993A/ja not_active Withdrawn
  • 2009-06-19 KR KR1020107017116A patent/KR101205676B1/ko not_active IP Right Cessation
  • 2009-06-19 AU AU2009318922A patent/AU2009318922B2/en not_active Ceased
  • 2009-06-19 CA CA2706347A patent/CA2706347C/en not_active Expired - Fee Related
  • 2009-06-19 US US12/810,542 patent/US20110146366A1/en not_active Abandoned

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