EP0148806A1 - Verfahren zum Rohrwalzen, welches es ermöglicht, die Leistung eines Kaltpilgerschrittwalzwerkes zu erhöhen, und Vorrichtung zur Bewerkstelligung des Verfahrens - Google Patents

Verfahren zum Rohrwalzen, welches es ermöglicht, die Leistung eines Kaltpilgerschrittwalzwerkes zu erhöhen, und Vorrichtung zur Bewerkstelligung des Verfahrens Download PDF

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Publication number
EP0148806A1
EP0148806A1 EP85420002A EP85420002A EP0148806A1 EP 0148806 A1 EP0148806 A1 EP 0148806A1 EP 85420002 A EP85420002 A EP 85420002A EP 85420002 A EP85420002 A EP 85420002A EP 0148806 A1 EP0148806 A1 EP 0148806A1
Authority
EP
European Patent Office
Prior art keywords
mandrel
rolling
upstream
blank
return
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.)
Granted
Application number
EP85420002A
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English (en)
French (fr)
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EP0148806B1 (de
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
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Vallourec SA
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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/de
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Publication of EP0148806B1 publication Critical patent/EP0148806B1/de
Expired legal-status Critical Current

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    • 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

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.
  • the process which is the subject of the invention relates to rolling mills with cold-arri steps which comprise a mandrel whose rolling range has a decreasing diameter from upstream to downstream. It consists of perform, at least once per rolling cycle, corresponding to a back and forth movement of the roll cage, a recoil movement of the mandrel along the rolling axis upstream, then back to its position initial.
  • This recoil and return movement of the mandrel can be carried out during the time when the blank is released from the grip of the cylinders in the vicinity of the upstream dead center and / or the 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 fluid is introduced in a particularly efficient way in 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 downstream of a first annular sealing means which provides 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 to the amomt through a passage formed in the mandrel.
  • 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 device making it possible to carry out the retraction then the return of the mandrel of a rolling mill with a cold crawl's step.
  • This device comprises a chuck rod clamp of known type which grips this rod in the vicinity of its rear end so as to keep it in a fixed position along the rolling axis; this rod clamp is mounted on a fixed support by means of a connecting means which allows the rod clamp to slide in a direction parallel to the rolling axis; an alternative drive means, controlled by the rolling cycle, causes the rod clamp to recoil at specified times with respect to this cycle, then return to its initial position with the desired amplitude and speed.
  • 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 XoX1 rolling axis.
  • 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 known type advances the blank downstream discontinuously, 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 movement of the tube along the rolling axis.
  • the pliers (4) rotates the chuck (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.
  • Figure 2 shows the mandrel (14) mounted at the end of the mandrel holder rod (2) in the normal rolling position inside the blank (1).
  • the method described comprises a single rolling pass during the outward stroke from the cylinder holder cage (6) downstream.
  • Figure 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 zone (15) partially laminated.
  • the amplitude of the recoil "L" 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 of amplitude "1" of the tube blank (1) causes the formation only of a very narrow annular passage, as seen in (18) Figure 4, after the return of the mandrel 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 "L” of the recoil of the mandrel is preferably adjusted to 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 (16) of the mandrel and the wall of the tube in the partially laminated area ( 15). It is possible as we will see to direct the flow of the fluid (s), it is also possible, in the most frequent case where each round trip of the cylinder carrier cage (6) has only one pass .of rolling, most often during the outward 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 50X 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 mandrel holder rod (21).
  • a passage (23) communicates the interior (24) of the rod (21) with the annular space (25) between the part (22) and the tube blank (20) upstream of the range of rolling (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).
  • 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) communicates the interior (37) of the rod (33) with the annular space (38), between the connecting piece (34) and the tube blank (32) upstream of the rolling range (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 as 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 joint (42) with the annular space (48) in upstream of the seal (39).
  • one or more fluids can be circulated under pressure originating 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).
  • 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 was 88.9 mm in outside diameter and 13.4 mm thick.
  • 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 holder 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 previous axes.
  • This pusher It actuates a pusher (62) via 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 end. downstream.
  • the recoil is carried out at the desired times. from the mandrel upstream, 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).

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  • 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)
  • Thermal Insulation (AREA)
  • Laminated Bodies (AREA)
  • Making Paper Articles (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 Verfahren zum Rohrwalzen, welches es ermöglicht, die Leistung eines Kaltpilgerschrittwalzwerkes zu erhöhen, und Vorrichtung zur Bewerkstelligung des Verfahrens Expired EP0148806B1 (de)

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 true EP0148806A1 (de) 1985-07-17
EP0148806B1 EP0148806B1 (de) 1987-11-25

Family

ID=9300211

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85420002A Expired EP0148806B1 (de) 1984-01-05 1985-01-03 Verfahren zum Rohrwalzen, welches es ermöglicht, die Leistung eines Kaltpilgerschrittwalzwerkes zu erhöhen, und Vorrichtung zur Bewerkstelligung des Verfahrens

Country Status (9)

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

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2640892A1 (de) * 1988-12-23 1990-06-29 Mannesmann Ag

Families Citing this family (10)

* 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
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
EP1884296B1 (de) * 2005-05-27 2011-09-21 Sumitomo Metal Industries, Ltd. Verfahren zur herstellung eines metallrohrs mit ultradünnen wänden durch ein kaltverarbeitungsverfahren
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

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1555869A (de) * 1967-12-20 1969-01-31
FR2234052A1 (de) * 1973-06-20 1975-01-17 Mannesmann Meer Ag

Family Cites Families (7)

* 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
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
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

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1555869A (de) * 1967-12-20 1969-01-31
FR2234052A1 (de) * 1973-06-20 1975-01-17 Mannesmann Meer Ag

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2640892A1 (de) * 1988-12-23 1990-06-29 Mannesmann Ag

Also Published As

Publication number Publication date
ES539330A0 (es) 1987-02-16
US4713955A (en) 1987-12-22
DE3561043D1 (en) 1988-01-07
FR2557819A1 (fr) 1985-07-12
JPS60158905A (ja) 1985-08-20
US4658617A (en) 1987-04-21
ES8703309A1 (es) 1987-02-16
BR8500017A (pt) 1985-08-13
EP0148806B1 (de) 1987-11-25
ATE31034T1 (de) 1987-12-15
CA1259828A (fr) 1989-09-26
FR2557819B1 (fr) 1986-05-02
JPH0261842B2 (de) 1990-12-21

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