EP0148806B1 - Procédé de laminage de tube permettant d'accroître les performances des laminoirs pèlerins à froid et dispositif pour la mise en oeuvre de ce procédé - Google Patents

Procédé de laminage de tube permettant d'accroître les performances des laminoirs pèlerins à froid et dispositif pour la mise en oeuvre de ce procédé Download PDF

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Publication number
EP0148806B1
EP0148806B1 EP85420002A EP85420002A EP0148806B1 EP 0148806 B1 EP0148806 B1 EP 0148806B1 EP 85420002 A EP85420002 A EP 85420002A EP 85420002 A EP85420002 A EP 85420002A EP 0148806 B1 EP0148806 B1 EP 0148806B1
Authority
EP
European Patent Office
Prior art keywords
mandrel
rolling
blank
movement
tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP85420002A
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German (de)
English (en)
French (fr)
Other versions
EP0148806A1 (fr
Inventor
Pierre Peytavin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vallourec SA
Original Assignee
Vallourec SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Vallourec SA filed Critical Vallourec SA
Priority to AT85420002T priority Critical patent/ATE31034T1/de
Publication of EP0148806A1 publication Critical patent/EP0148806A1/fr
Application granted granted Critical
Publication of EP0148806B1 publication Critical patent/EP0148806B1/fr
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B25/00—Mandrels for metal tube rolling mills, e.g. mandrels of the types used in the methods covered by group B21B17/00; Accessories or auxiliary means therefor ; Construction of, or alloys for, mandrels or plugs
    • B21B25/04—Cooling or lubricating mandrels during operation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B21/00—Pilgrim-step tube-rolling, i.e. pilger mills
    • B21B21/005—Pilgrim-step tube-rolling, i.e. pilger mills with reciprocating stand, e.g. driving the stand
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B21/00—Pilgrim-step tube-rolling, i.e. pilger mills
    • B21B21/04—Pilgrim-step feeding mechanisms
    • B21B21/045—Pilgrim-step feeding mechanisms for reciprocating stands
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B21/00—Pilgrim-step tube-rolling, i.e. pilger mills
    • B21B21/06—Devices for revolving work between the steps
    • B21B21/065—Devices for revolving work between the steps for reciprocating stands

Definitions

  • the method and the device which are the subject of the invention relate in the most general way to the operation of rolling mills with cold crawl steps for the rolling of tubes. It relates more particularly to rolling mills of this type used for the rolling of tubes in particular of large diameter steel with high reduction rates.
  • Such rolling mills in known manner have grooved cylinders mounted in a cylinder cage which performs a reciprocating movement along the rolling axis, the blank of tube to be laminated being periodically advanced along the axis of rolling downstream.
  • a mandrel is placed inside the blank along the rolling axis and in a fixed axial position relative to the latter.
  • Such a rolling mill is for example described in FR-A-1 555 869 which is concerned only with the carrying out of the back and forth movement along the rolling axis of the roll holder cage.
  • the tube rolling process which is the subject of the invention uses a cold crawl rolling mill comprising cylinders mounted in a cylinder cage which performs a back and forth movement along the rolling axis of said rolling cylinders the tube blank, which is periodically advanced, on a mandrel disposed inside the blank and held in the axial position.
  • the mandrel has a rolling range of decreasing diameter from upstream to downstream.
  • one or more fluids under pressure are circulated, successively or simultaneously, in the annular space between the mandrel and the tube blank .
  • This recoil movement and then the return movement of the mandrel can be carried out in the vicinity of the upstream dead center and / or downstream dead center of the cylinder holder cage.
  • the amplitude of the recoil of the mandrel is preferably between 2 and 10 times the amplitude of the advance given to the blank before each rolling pass.
  • the fluids injected can be gaseous or liquid fluids, the latter preferably being lubricants. These fluids are preferably injected under a pressure of 2 to 20 bar relative.
  • the fluid is introduced in a particularly efficient manner into the annular space between the connecting piece which connects the mandrel to the mandrel holder rod and the tube blank, upstream of the rolling surface of the mandrel and in downstream of a first annular sealing means which ensures dynamic sealing between the connecting piece and the tube and forces the fluid to flow downstream between the rolling surface of the mandrel and the tube blank.
  • a second annular sealing means is advantageously disposed downstream of the rolling surface, it provides dynamic sealing between the mandrel and the tube blank and forces the fluid (s) to return upstream through a passage formed in the mandrel.
  • These dynamic seals can be of any known type, such as lip seals, or O-rings; it is also possible to use metallic seals such as segments or toroids with metallic envelopes or the like.
  • the invention also relates to a rolling mill for implementing the method described above making it possible to carry out the retraction and then the return of the mandrel of a rolling mill with vocational steps when cold.
  • This cold vocational rolling mill for tubes comprises rolls mounted in a roll-carrying cage which moves back and forth along the rolling axis as well as means for holding and periodically advancing the blank of tube and a mandrel which has a rolling bearing of decreasing diameter from upstream to downstream and which is mounted on a mandrel holder rod, said mandrel being disposed inside the blank and held in axial position by a clamp -stem mounted in the vicinity of the rear end of the rod.
  • the rod clamp is mounted on a fixed support by means of a connecting means allowing sliding in a direction parallel to the rolling axis.
  • An alternative drive means controlled by the rolling cycle, causes, at instants determined with respect to this cycle corresponding to times when the preform is released from the grip of the rolls taking place during the rolling phase (s) , the retraction of the pliers in the upstream direction then its return to the initial position with the desired amplitude and speed.
  • a means for introducing pressurized fluid makes it possible to circulate a fluid in the annular space between the mandrel and the blank tube, at least during the period during which the mandrel is set back from its rolling position.
  • the reciprocating drive of the pliers is preferably carried out by means of a cam. Between the end of the recoil of the rod clamp and its return to its initial position, it is possible to provide a time for holding in the withdrawal position.
  • An advantageous application of the method and the device according to the invention relates to the case where it is proposed to carry out a double advance of the blank at the upstream and downstream dead centers. We can then perform simultaneously, in the vicinity of each of these two dead centers, a movement of withdrawal and then return of the mandrel which allows effective lubrication and cooling. We can then perform two rolling passes in each cycle.
  • Figure 1 is a schematic perspective view of a cold crawl pitch rolling mill operated by the method according to the invention.
  • the tube blank 1 slides around a mandrel holder rod 2 along the rolling axis XoX1.
  • the rear end 3 of the rod 2 is held by a rod clamp 4 which can cause the rod 2 to rotate about its axis, and also move it alternately along its axis along the double arrow F.
  • a pushing means 5 of a known type advances the blank discontinuously downstream, at time intervals synchronized with the successive rolling cycles of the cylinder holder cage 6.
  • Each cycle includes a back and forth movement of the stand 6 along the rolling axis.
  • the rolling rolls 7 and 8 are rotated sometimes in one direction sometimes in the other. They laminate the tube blank 1 by means of their grooves 9 and 10 which cooperate with the mandrel, not shown, to lengthen the blank and to thin its walls.
  • the tube clamps 11 and 12 rotate the blank 1 upstream in its laminated part 13 downstream of the cage 6, during the periods when it is released from the grip of the cylinders, without obstructing the movements of the tube along of the rolling axis.
  • the rod clamp 4 rotates the mandrel carrier rod 2 in synchronism with the blank 1 and moves it along the arrow F in the manner which will be specified.
  • FIGS 2, 3 and 4 schematically show the operation of the mandrel used on the rolling mill of Figure 1.
  • FIG. 2 shows the mandrel 14 mounted at the end of the carrier rod 2 in the normal rolling position inside the blank 1.
  • the process described comprises a single rolling pass during the outward stroke of the carrier cage cylinders 6 downstream.
  • FIG. 2 corresponds to the moment when the cylinder holder cage 6 completes its stroke back upstream, and releases the blank 1 from its grip in the partially laminated zone 15.
  • the amplitude of the recoil "1" is determined so as to provide, between the rolling surface 16 of the mandrel and the wall of the tube in the zone 15, an annular passage 17 of relatively large section.
  • the only advance in amplitude "1" of the tube blank 1 causes only a very narrow annular passage to be formed, as can be seen in FIG. 4, after the mandrel has returned to its rolling position. .
  • This passage is all the narrower that the actual slope of the rolling range of a mandrel is much lower than that shown in these three diagrams.
  • the amplitude "1" of the recoil of the mandrel is preferably adjusted a value between 2 and 10 times the amplitude "1" of the advance given to the blank.
  • One of the most important is the injection of one or more liquid or gaseous fluids simultaneously or successively into the space between the rolling surface 15 of the mandrel and the wall of the tube in the partially laminated area 16. It it is possible as will be seen to direct the flow of the fluid or fluids, it is also possible, in the most frequent case where each round trip of the cylinder carrier cage 6 has only one rolling pass, most often during the forward stroke of the cage in the downstream direction, to put the mandrel in the recoil position from the downstream dead center and thus maintain it until the upstream dead center. The circulation of the fluid (s) is then allowed for approximately 50% of the operating time.
  • FIGS 5 and 6 describe two types of mandrel particularly suitable for operating the method according to the invention.
  • FIG. 5 shows a mandrel 19 inside a blank of tube 20 during rolling.
  • a connecting piece 22 assembled by a threaded junction 29 with the mandrel, connects the latter to the hollow rod carrying the mandrel 21.
  • a passage 23 places the interior 24 of the rod 21 in communication with the annular space 25 between the part 22 and the tube blank 20 upstream of the rolling surface 26 of the mandrel.
  • a first annular sealing means is constituted by a dynamic lip seal 27 placed in a groove 28 formed around the connecting piece 22.
  • the lip seal can be replaced by another type of seal such as an O-ring.
  • One can also use a metal joint such as a segment.
  • the assembly between the connecting piece 22 and the mandrel 19 can be carried out by any means such as welding, soldering or the like. These two parts can also be produced in a single monobloc assembly; similarly the junction between the connecting piece 22 and the mandrel holder rod 21 can be achieved by any suitable means such as screwing, welding, brazing or other.
  • Figure 6 a second type of mandrel 30 comprising like that of Figure 5 a rolling surface 31. It is housed inside a tube blank 32 during rolling. A connecting piece 34 is connected on the one hand to the mandrel 30 by the threaded junction 35 and on the other hand to the hollow mandrel-holding rod 33.
  • a first passage means 36 places the interior 37 of the rod 33 in communication with the annular space 38, comprised between the connecting piece 34 and the tube blank 32 upstream of the rolling surface 31.
  • This space is closed upstream by the dynamic lip seal 39 housed in the groove 40.
  • a second annular sealing means is constituted by the dynamic seal 42 housed in the groove 43.
  • This seal of design similar to those described above is advantageously metallic, for example in the form of a segment. It may include several successive elements, which may also be the case for the first sealing means.
  • a second passage means constituted by the radial channels 45 and 46 and the longitudinal channel 44, connects the annular space 47 upstream of the seal 42 with the annular space 48 upstream of the seal 39.
  • one or more fluids can be circulated under pressure coming from the hollow rod at 37 through the passage 36 then in the annular space 38 and then between the rolling surface 31 and the blank 32 downstream. This or these fluids then return upstream through the channels 45, 44 and 46 and through the annular space 48. It is also possible to envisage organizing the circulation of this or these fluids in the opposite direction.
  • the method according to the invention is applied by way of example, using this lubrication mode, and this type of mandrel shown in FIG. 5.
  • steel tube blanks of type AISI 321, having a outer diameter of 133 mm and a thickness of 20 mm.
  • the rate is 120 rolling cycles per minute with a single rolling pass and a single feed per cycle.
  • the tube obtained is 88.9 mm in outside diameter and 13.4 in thickness.
  • the blank is advanced by 9.4 mm and the mandrel moves back by 30 mm with return to its initial position.
  • a lubricant of known type in space 25 is injected under a pressure of about 10 relative bars.
  • This lubricant circulates, as has just been described, around the rolling surface 26 of the mandrel 19, at each retraction of this mandrel. This produces tubes rolled at a rate of about 150 meters per hour. It can be seen that the surface condition of the internal wall of these tubes is excellent.
  • the invention also relates to a device which makes it possible to carry out in a simple manner the movements of retraction then of return of the mandrel, in a synchronized manner with the outward and return cycles of the cylinder holder cage.
  • FIGS. 7 and 8 show, diagrammatically, an embodiment of a pliers-rod whose function is that of that represented in 4 FIG. 1.
  • This rod clamp 49 encloses a mandrel carrier rod 50 in the vicinity of its upstream end 51. It maintains the rod 50 in a fixed position along the axis X O X 1 during the rolling passes. It also rotates it around its axis by fraction of a turn as described above.
  • the sliding of the rod clamp 49 is controlled by a retaining part R, arranged in the extension of the slide.
  • This part consists of two similar elongated rigid elements 55 and 56, arranged end to end, and articulated relative to each other around the axis 57.
  • the free end of the element 55 is articulated around the axis 58, mounted on the fixed part 52.
  • the free end of the element 56 is articulated around the axis 59, mounted at the front end of the base plate 53.
  • the axes 57, 58 and 59 are mutually parallel and perpendicular to the plane of the figure.
  • a cam 60 rotates around an axis 61, parallel to the parent axes.
  • a pusher 62 It actuates a pusher 62 by means of a roller 63.
  • This pusher is articulated around the axis 57 and therefore makes it possible to separate this axis from the straight line which joins the axes 58 and 59.
  • the distance between the axes 58 and 59 is then reduced and the rod clamp 49 is then moved upstream by driving the mandrel holder rod 50 and therefore the mandrel which is fixed at its downstream end.
  • the recoil of the mandrel is carried upstream at the desired times. , then its return to its initial position, with the desired amplitude and in a strictly determined time interval.
  • roller 63 is held in abutment on the cam 60 by the arm 65, which is articulated around the axis 66 and which is pulled by the return spring 67.
  • arm 65 which is articulated around the axis 66 and which is pulled by the return spring 67.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Metal Rolling (AREA)
  • Control Of Metal Rolling (AREA)
  • Forging (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
  • Making Paper Articles (AREA)
  • Thermal Insulation (AREA)
  • Laminated Bodies (AREA)
  • Saccharide Compounds (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Apparatuses For Bulk Treatment Of Fruits And Vegetables And Apparatuses For Preparing Feeds (AREA)
EP85420002A 1984-01-05 1985-01-03 Procédé de laminage de tube permettant d'accroître les performances des laminoirs pèlerins à froid et dispositif pour la mise en oeuvre de ce procédé Expired EP0148806B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85420002T ATE31034T1 (de) 1984-01-05 1985-01-03 Verfahren zum rohrwalzen, welches es ermoeglicht, die leistung eines kaltpilgerschrittwalzwerkes zu erhoehen, und vorrichtung zur bewerkstelligung des verfahrens.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8400697 1984-01-05
FR8400697A FR2557819B1 (fr) 1984-01-05 1984-01-05 Procede permettant d'accroitre les performances des laminoirs a pas de pelerin a froid, et dispositif pour la mise en oeuvre de ce procede

Publications (2)

Publication Number Publication Date
EP0148806A1 EP0148806A1 (fr) 1985-07-17
EP0148806B1 true EP0148806B1 (fr) 1987-11-25

Family

ID=9300211

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85420002A Expired EP0148806B1 (fr) 1984-01-05 1985-01-03 Procédé de laminage de tube permettant d'accroître les performances des laminoirs pèlerins à froid et dispositif pour la mise en oeuvre de ce procédé

Country Status (9)

Country Link
US (2) US4658617A (enrdf_load_stackoverflow)
EP (1) EP0148806B1 (enrdf_load_stackoverflow)
JP (1) JPS60158905A (enrdf_load_stackoverflow)
AT (1) ATE31034T1 (enrdf_load_stackoverflow)
BR (1) BR8500017A (enrdf_load_stackoverflow)
CA (1) CA1259828A (enrdf_load_stackoverflow)
DE (1) DE3561043D1 (enrdf_load_stackoverflow)
ES (1) ES8703309A1 (enrdf_load_stackoverflow)
FR (1) FR2557819B1 (enrdf_load_stackoverflow)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3709008C1 (de) * 1987-03-19 1988-02-25 Mannesmann Ag Dreh- und Vorschubeinrichtung zum absatzweisen Walzen langgestreckter Werkstuecke auf einem Kaltpilgerwalzwerk
DE3717165C1 (en) * 1987-03-26 1988-03-31 Mannesmann Ag Method for the production of tubes by the cold reciprocating rolling method
DE3844163A1 (de) * 1988-12-23 1990-07-05 Mannesmann Ag Verfahren und vorrichtung zum schmieren des dornes beim herstellen nahtloser rohre nach dem kaltpilgerverfahren
US5016460A (en) * 1989-12-22 1991-05-21 Inco Alloys International, Inc. Durable method for producing finned tubing
FR2759483B1 (fr) * 1997-02-12 1999-04-30 Zircotube Procede de fabrication d'un tube-guide d'un assemblage de combustible d'un reacteur nucleaire, mandrin de formage d'un tube-guide et tube-guide obtenu
DE19911677C1 (de) * 1999-03-09 2000-05-04 Sms Demag Ag Kaltpilgerwerkzeug zum Herstellen von innenverrippten Rohren
JP3073981B1 (ja) * 1999-03-19 2000-08-07 核燃料サイクル開発機構 鉄基分散強化型合金管の製造方法
BRPI0610086A2 (pt) * 2005-05-27 2008-12-02 Sumitomo Metal Ind mÉtodo para produzir tubo metÁlico com parede ultra fina, com processo de trabalho a frio
ES2536183T3 (es) * 2007-12-05 2015-05-21 Nippon Steel & Sumitomo Metal Corporation Procedimiento de fabricación de tuberías de metal con pared extremadamente delgada mediante laminado en frío
US8161786B2 (en) * 2008-04-15 2012-04-24 Glen Stapleton Apparatus for feeding and turning tube products into a pilger mill machine
DE102009003175A1 (de) * 2009-05-15 2010-11-18 Sandvik Materials Technology Deutschland Gmbh Vorschubantrieb für eine Kaltpilgerwalzanlage

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1980186A (en) * 1931-02-19 1934-11-13 American Brass Co Tube reducing means
US2703999A (en) * 1953-11-24 1955-03-15 See Fabriks Aktiebolag Pilgrim rolling mills
FR1555869A (enrdf_load_stackoverflow) * 1967-12-20 1969-01-31
SU395128A1 (ru) * 1971-10-12 1973-08-28 Уральский политехнический институт С. М. Кирова Способ холодной прокатки труб
US3813911A (en) * 1972-10-18 1974-06-04 Superior Tube Co Tube rolling mill for producing tubing with various internal configurations
DE2331989A1 (de) * 1973-06-20 1975-01-23 Mannesmann Meer Ag Stopfenstange fuer kontinuierliche rohrwalzwerke
DE2749102A1 (de) * 1977-10-31 1979-05-03 Mannesmann Ag Warmpilgerwalzwerk
US4184352A (en) * 1978-06-08 1980-01-22 Moskovsky Institut Stali I Splavov Method for pilger rolling of tubes and mill for effecting same
JP3461422B2 (ja) * 1996-06-14 2003-10-27 株式会社リコー 画像形成装置

Also Published As

Publication number Publication date
ES539330A0 (es) 1987-02-16
ES8703309A1 (es) 1987-02-16
FR2557819B1 (fr) 1986-05-02
JPH0261842B2 (enrdf_load_stackoverflow) 1990-12-21
US4713955A (en) 1987-12-22
BR8500017A (pt) 1985-08-13
FR2557819A1 (fr) 1985-07-12
CA1259828A (fr) 1989-09-26
EP0148806A1 (fr) 1985-07-17
ATE31034T1 (de) 1987-12-15
US4658617A (en) 1987-04-21
JPS60158905A (ja) 1985-08-20
DE3561043D1 (en) 1988-01-07

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