US3719066A - Piercing rolling apparatus for producing rolled material free from surface torsion - Google Patents

Piercing rolling apparatus for producing rolled material free from surface torsion Download PDF

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Publication number
US3719066A
US3719066A US00084663A US8466370A US3719066A US 3719066 A US3719066 A US 3719066A US 00084663 A US00084663 A US 00084663A US 8466370 A US8466370 A US 8466370A US 3719066 A US3719066 A US 3719066A
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United States
Prior art keywords
angle
rolls
axis
billet
gamma
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Expired - Lifetime
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US00084663A
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English (en)
Inventor
T Okamoto
C Hayashi
M Nishiguchi
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Nippon Steel Corp
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Sumitomo Metal Industries Ltd
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Priority claimed from JP8893769A external-priority patent/JPS4923473B1/ja
Priority claimed from JP472970A external-priority patent/JPS4923756B1/ja
Application filed by Sumitomo Metal Industries Ltd filed Critical Sumitomo Metal Industries Ltd
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Publication of US3719066A publication Critical patent/US3719066A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B19/00—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work
    • B21B19/02—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work the axes of the rollers being arranged essentially diagonally to the axis of the work, e.g. "cross" tube-rolling ; Diescher mills, Stiefel disc piercers or Stiefel rotary piercers
    • B21B19/04—Rolling basic material of solid, i.e. non-hollow, structure; Piercing, e.g. rotary piercing mills

Definitions

  • ABSTRACT A piercing rolling apparatus utilizing the principle of the Stiefel Mannesmann type piercing mill and having two main rolls axes of which incline with each other vertically at the feed angle [3 with respect to the 1ongitudinal axis of the material to be rolled and cross with each other horizontally at the cross angle 7 with respect to the longitudinal axis of the material.
  • a seamless steel pipe free from surface torsion is obtained by adjusting these angles B and 'y.
  • SHEET 4 OF 6 CROSS ANGLE 2 4 is 8 lb :2 1'4 1'6 FEED ANGLE (B) PATENTEDHAR- 61975 5,719,066
  • the present invention relates to an improved piercing mill to prevent surface torsion of the rolled material in mass production of seamless steel pipe, particularly in a Stiefel Mannesmann type piercing mill.
  • the Stiefel Mannesmann type continuous process comprising in sequential arrangement a piercing mill, plug mill, reeling mill, reducing mill and sizing mill.
  • a round billet previously heated to a hot rolling temperature by a heating furnace is pierced by the shaping rolls of the piercing mill. Since the hollow piece obtained in this way is short and very thick, it is subsequently reduced in thickness and elongated in length by the plug mill, reeled on the inner and outer surfaces by the reeling mill to the specified thickness,
  • suc-' ceeding sizing mill into the desired.
  • it may be further heated in a reheating furnace, reduced to a tube of small diameter and then cut to the prescribed length of the product.
  • An object of this invention is to prevent surface twisting of the rolled material caused by torsional forces, to improve the surface condition of the produced pipe or tube and thus to promote products yield in the Stiefel Mannesmann type piercing mill employed in production of seamless steel pipe.
  • Another object of the present invention is to provide a mill construction having a piercing mill providing the foregoing object.
  • the objects of the present invention are attained by mounting the rolls to have a cross angle 7, adjusting the base of the main rolls on a fixed base of the piercing mill rotatably with respect to the longitudinal axis of the material to be rolled, mounting a supporting frame of the main rolls on the cross angle adjusting the base rotatably with respect to the longitudinal axis of the material and mounting a roll opening adjusting device on the cross angle adjusting base.
  • FIG. 1 is a top view showing an arrangement of main rolls of a conventional piercing mill.
  • FIG. 2 is a side view of the arrangement shown in FIG. 1.
  • FIG. 3 is a partial sectional view taken along the line III-III of FIG. 2.
  • FIGS. 4A to D are perspective views each showing a model billet comprising plasticine in two colors and model hollow pieces formed out of the model billets by various model piercing mills.
  • FIG. 5 is a top view of a main rolls arrangement of a piercing mill according to the present invention.
  • FIG. 6 is a side view of the arrangement shown in FIG. 5.
  • FIG. 7 is a partial sectional view taken along the line VII-VII of FIG. 6.
  • FIG. 8 is a graphical illustration of the relationship between the feed angle B and the cross angle y of the main rolls according to the present invention.
  • FIG. 9 is a front view showing a construction of a piercing apparatus embodying the present invention.
  • FIG. 10 is a sectional view taken along the line X-X of FIG. 9.
  • FIG. 11 is a sectional view taken along the line XI- XI of FIG. 10.
  • FIG. 12 is a partial side view showing the inclining relationship between the two main rolls.
  • main rolls 1, 1 have the largest diameters at their longitudinal centers and are in a bisymmetric barrel shape with a surface angle a selected in the range 3 5.
  • the aforementioned largest diameters of the rolls are larger than the length thereof.
  • the axes of the main rolls are in parallel with each other when seen from the top but incline with respect to each other as seen from the side.
  • the the axes are provided with a feed angle B selected in the range 5 13 vertically with respect to the longitudinal axis of the material to be rolled or the billet 3 (FIG. 2).
  • guide shoes 2, 2 In the upper and lower spaces between the main rolls are provided guide shoes 2, 2 for supporting the rotating hollow piece 8 during rolling.
  • a piercing plug 4 is positioned by a mandrel 5 a prescribed distance from the gorge toward the entrance side of the mill.
  • the main rolls rotate in the same direction, as shown by arrows 6 and 7.
  • the billet 3 heated up to the rolling temperature is introduced from the roll entrance, it is fed toward the gorge by the function of the feed angle B and rapidly rotates in to the direction contrary to that of the main rolls. Since the gap between the main rolls 1, 1 becomes narrower as it comes close to the gorge, the billet 3 is rotatingly pressed repeatedly by the surfaces of the main rolls and grows into a condition tending to form a hole at the center. As a result, it is easily pierced by the pointed head of the plug 4.
  • the plug 4 Since the plug 4 is so maintained that it will rotate freely together with the mandrel 5 in accordance with the rotation of the work piece but will not move backward, the hollow piece 8 is reduced in thickness, and being subject to the radial plastic deformation due to the interaction between the main rolls and the plug, it increases its inner diameter.
  • the outer diameter of the piece 8 is increased a little according to the surface angle a, at the exit side of the rolls.
  • this billet 3 becomes a hollow piece 8 with a thick wall and short size.
  • the main rolls 11, 11 to be used in the present invention are basically of the barrel type and it is preferably that their cutting angles 0, and 0, with the roll axes toward the entrance and the exit 0 should satisfy the relation
  • the axes of the main rolls 11, ll incline towards each other vertically at the feed angle B with respect to the longitudinal axis of the material to be rolled or the billet 13 (see FIG. 6) and intersect each other horizontally at the cross angle 7 with respect to said axis (see FIG.
  • the main rolls 11, 11 are rotated in the same direction, as shown by the arrows l6 and 17.
  • Guide shoes I2, 12 are provided between the rolls ll, 11 for supporting the hollow piece 18 from the upper and lower sides during rolling (see FIG. 7).
  • a plug 14 for piercing the billet is positioned by a mandrel 15 at a distance toward the entrance from the gorge.
  • the two main rolls in the conventional Stiefel Mannesmann piercing method have the surface angle a and the feed angle 8 but not cross angle corresponding to the angle 7 in FIG. 5 of the present invention.
  • the present invention it is possible to obtain a hollow piece completely or substantially free from surface twisting or torsion by selecting the feed angle and the cross angle properly.
  • Metal flow of the billet is experimentally visualized in FIG. 4 which shows the effect on model hollow pieces made of model billets of plasticine (a trade name of a kind of clay) of two colors pierced by a model piercing mil.
  • the optimum feed angle 3 and cross angle 7 may be experimentally obtained using the model billets.
  • a model starting billet of 47 mm in diameter and 120 mm in length is made by adhering two semi-cylindrical sections of plasticine of two colors respectively.
  • FIG. 48 For the comparison of the present invention with the prior art technique, a hollow piece formed by a model piercing mill of the conventional Stiefel Mannesmann type is shown in FIG. 48. On the surface of the model hollow piece appears a spiral surface twists, as seen in the drawing. Another hollow piece formed by a model piercing mill using the conventional cone type rolls is shown in FIG. 4C wherein a spiral surface twist appears, twisted to the direction contrary to that of the FIG. 48. It is absolutely impossible toprevent torsion on the surface of the billets by the prior art techniques, no matter in what manner the surface angle a or feed angle 3 are changed.
  • the feed angle 62 may be determined arbitrarily. However, in the range smaller than 2, it is not practical since the feeding of the billet, namely through productivity, is too low, and in the range larger than 16, it is not practical as well since the opposing cross angle 7 approaches 45.
  • the surface angle a, of the rolls is kept constant at 3.5.
  • the suitable range of the surface angle a, of the rolls is between 2-6. if the angle a, is larger than 6, advancement of the billet becomes difficult, and if it is smaller than 2, initial feeding of the material is obstructed. From the aforementioned reason, the optimum range of the cross angle y of the rolls is between the lower limit of 3 and the upper limit corresponding to percent of 'y of the equation (1), in other words, the angle 7 may be selected arbitrarily within the obliquely lined region in FIG. 8.
  • FIGS. 9 l2 apparatus for carrying out present invention is shown.
  • the apparatus is provided with a fixed base 22 secured to the foundation by four columns 21 and a removable base plate 23.
  • a cross angle adjusting base 24 of C-shaped section is mounted on the fixed base 22 by a shaft column 25 so as to be able to rotate on a horizontal plane.
  • the side of the cross angle adjusting base 24 facing the main roll is formed in a circulararc provided with gear teeth 26.
  • a worm gear 27 is adapted to intermesh with the gear teeth 26.
  • the worm gear 27 is mounted on an elongated shaft 28, whose gear 29, meshes with a common pinion 30 driven by an electric motor 31
  • the cross angle adjusting base 24 may thus be rotated with the as described below.
  • the roll housing 43 has a cross section of C-shape and a vertical section of partially notched cylindrical shape, as shown in FIG. 11.
  • the upper part of the housing is slidably supported by the sliding guide 44 of circular arc shape.
  • the lower part of the housing forms a boss 45 against both sides of which cylinder rods 46 press and the tip of a rotary driver 47 contacts.
  • the cylinder rods 46 are supported by an oil pressure cylinder 48, whereas the rotary driving shaft 47 is connected to a series of transmission gears consisting of a gear 49, a pinion (not shown) to intermesh with the gear, a shaft 50 connected to the pinion and a driving motor 51 fixed to the cross angle adjusting base 24. Operation of the driving shaft 47 adjusts the feed angle B of the main roll by pushing the lower boss 45 of the roll housing in response to the rotary driving of the electric motor 51.
  • the adjustment range of the shaft is 0 16.
  • two supporting shafts 58 adjust the roll opening of the main rolls by forward and backward movements when rotatably driven by two gears 57 rotated by a power transmission comprising an electric motor 52, a gear 53 rotated by said motor 52, a gear 54 intermeshed by the gear 53, a worm gear 55 intermeshed by the gear 54 and a shaft 56 connected directly to the gear 55.
  • the piercing plug 62 is supported by a mandrel 61 between rolls 41 at the gorge.
  • the billet is introduced in the direction denoted by an arrow 70 and rotatingly pierced by the interaction of the main rolls and the plug.
  • the hollow piece is supported by the upper and lower guide shoes 63 and 64.
  • the vertical position of the upper guide shoe is adjusted by a shaft 66 which is connected to a guide shoe holder 65 and is driven by a worm gear 67 and a driving motor therefor.
  • the lower guide shoe is adjusted by conventional methods such by replacing the shoe 64 with one of a different size or, insertion of a liner Rotation of the main rolls is obtained through a drive and a conventional transmission gear such as universal coupling provided on the roll shaft at the entrance side of the billet to be rolled.
  • the main rolls 41, 41 are mounted with the feed angle B and the cross angle 7 with each other. Moreover, in order to provide the entrance and exit sides of the rolls to the material to be rolled with the surface angle of 2 6, it is preferable that the main rolls be provided with the entrance and exit sides cutting angles 0 and 0 which will satisfy the following angular condition:
  • a piercing rolling mill of the Stiefel Mannesmann type for producing hollow seamless pieces comprising in combination: a pair of rolls between which a billet is fed, rolled and advanced to a hollow piece substantially free of surface torsion, means for driving said rolls, and means for adjustably mounting said rolls between a feed angle B and a cross angle 7, said angle B being taken in the horizontal plane and defining the angle between the axis of the rolls and the billet axis, said angle 7 being taken in the vertical plane and defining the angle between the axis of the rolls and the billet axis, the angles B and 7 being variable in the range satisfying the condition expressed by the following equation:
  • each of said rolls has entrance surface angle 01 and exit surface angle a, taken in the vertical plane, said angles 0: and a defining the angle of the said surface to the billet axis and selected in the range between 2 and 6; and wherein each of said rolls has entrance cutting angle 0, and exit cutting angle 0 said angles 0 and 0 defining the angle of the said surface to the billet when taken in the horizontal plane and satisfying the conditions expressed by the following equations:
  • the adjustable mounting means includes a pair of opposed bases, each of said bases being mounted for rotation about a fixed axis vertical to the billet, axis, a housing mounted on each of said bases, said housings being pivotal about an axis parallel to said associated vertical axis, said rolls being journaled respectively in said housings, means for rotating said base to adjust the angle a and means for pivoting said housing to adjust the angle B.
  • the mill of claim 3 including means for limiting the rotation of said bases about the vertical axis to maintain said angle y between 3 and 30 and means to limit the pivoting of said housings to maintain the feed angle B between 2 to 16.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Metal Rolling (AREA)
  • Reduction Rolling/Reduction Stand/Operation Of Reduction Machine (AREA)
US00084663A 1969-11-05 1970-10-28 Piercing rolling apparatus for producing rolled material free from surface torsion Expired - Lifetime US3719066A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP8893769A JPS4923473B1 (fr) 1969-11-05 1969-11-05
JP472970A JPS4923756B1 (fr) 1970-01-16 1970-01-16

Publications (1)

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US3719066A true US3719066A (en) 1973-03-06

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US00084663A Expired - Lifetime US3719066A (en) 1969-11-05 1970-10-28 Piercing rolling apparatus for producing rolled material free from surface torsion

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US (1) US3719066A (fr)
BE (1) BE758174A (fr)
CA (1) CA919958A (fr)
DE (1) DE2054541A1 (fr)
FR (1) FR2068994A5 (fr)
GB (1) GB1320035A (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57168711A (en) * 1981-04-10 1982-10-18 Sumitomo Metal Ind Ltd Production of seamless steel pipe
US4827750A (en) * 1987-03-27 1989-05-09 Sumitomo Metal Industries, Ltd. Method of piercing and manufacturing seamless tubes
DE4140948A1 (de) * 1991-12-12 1993-06-17 Schwager Aribert Prof Dr Ing H Verfahren zur herstellung rohrfoermiger teile
EP0754503A1 (fr) * 1995-01-10 1997-01-22 Sumitomo Metal Industries, Ltd. Procede et appareil pour obtenir par per age des tuyaux metalliques sans soudure
US5649440A (en) * 1994-11-17 1997-07-22 Mannesmann Aktiengesellschaft Method for calibration of assel rollers
US20090113970A1 (en) * 2005-06-16 2009-05-07 V & M Deutschland Gmbh Method Of Making A Seamless Hollow Body From Steel
WO2020224758A1 (fr) 2019-05-06 2020-11-12 Vallourec Deutschland Gmbh Procédé et appareil de détermination d'un angle de torsion lors d'une opération de laminage
CN113680823A (zh) * 2021-08-31 2021-11-23 攀钢集团研究院有限公司 一种无缝钢管穿孔机及其顶头

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2814493C3 (de) * 1978-03-31 1980-12-18 Mannesmann Ag, 4000 Duesseldorf Schrägwalzwerk
DE3406841A1 (de) * 1984-02-23 1985-09-12 Mannesmann AG, 4000 Düsseldorf Walzenanstellung fuer ein dreiwalzen-kegelschraegwalzwerk
US4901553A (en) * 1987-06-03 1990-02-20 Sumitomo Metal Industries, Ltd. Method of manufacturing a finned tube
DE68909176T2 (de) * 1988-11-18 1994-01-13 Sumitomo Metal Ind Verfahren zur Herstellung nahtloser Rohre aus Titan.
EP1649945B1 (fr) * 2003-06-06 2011-01-26 Sumitomo Metal Industries, Ltd. Procede de per age/laminage destine a la fabrication d'un tube sans soudure
CN112024607B (zh) * 2020-08-26 2022-04-26 太原科技大学 一种锥齿轮传动的双环辊旋轧机构
CN111804855B (zh) * 2020-08-26 2022-08-02 太原科技大学 一种三自由度旋轧机
CN111842742B (zh) * 2020-08-26 2022-04-26 太原科技大学 一种锥齿轮传动的单环辊旋轧机构
CN112045120B (zh) * 2020-08-26 2022-01-28 太原科技大学 一种直齿轮传动的双环辊旋轧机构

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU160498A1 (fr) *
US1141426A (en) * 1911-05-03 1915-06-01 Frank E Simpkins Mandrel stripping and cooling mechanism.
US1587112A (en) * 1922-02-13 1926-06-01 Gassen Josef Rolling mill for pierced or solid metal blanks
US3512403A (en) * 1967-03-30 1970-05-19 Nippon Kokan Kk Method of determining the pierceability of seamless metal tubes
US3550415A (en) * 1969-01-13 1970-12-29 United States Steel Corp Feed and toe angle indicator for billet-piercing mill

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE185148C (fr) *
FR770039A (fr) * 1933-04-26 1934-09-06 Diescher Tube Mills Perfectionnements relatifs à un procédé de perçage d'ébauches métalliques pleines
US2103574A (en) * 1934-06-12 1937-12-28 John B Wintercorn Positively controlled tube bore mandrel for tube forming machines
FR1506669A (fr) * 1966-03-22 1967-12-22 Babcock & Wilcox Co Procédé de perçage pour la production de tubes

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU160498A1 (fr) *
US1141426A (en) * 1911-05-03 1915-06-01 Frank E Simpkins Mandrel stripping and cooling mechanism.
US1587112A (en) * 1922-02-13 1926-06-01 Gassen Josef Rolling mill for pierced or solid metal blanks
US3512403A (en) * 1967-03-30 1970-05-19 Nippon Kokan Kk Method of determining the pierceability of seamless metal tubes
US3550415A (en) * 1969-01-13 1970-12-29 United States Steel Corp Feed and toe angle indicator for billet-piercing mill

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57168711A (en) * 1981-04-10 1982-10-18 Sumitomo Metal Ind Ltd Production of seamless steel pipe
DE3212742A1 (de) * 1981-04-10 1982-11-04 Sumitomo Kinzoku Kogyo K.K., Osaka Lochungsverfahren bei der herstellung nahtloser rohre
US4470282A (en) * 1981-04-10 1984-09-11 Sumitomo Kinzoku Kogyo Kabushiki Gaisha Method of piercing in seamless tube manufacturing
JPS6059042B2 (ja) * 1981-04-10 1985-12-23 住友金属工業株式会社 継目無鋼管の製造方法
US4827750A (en) * 1987-03-27 1989-05-09 Sumitomo Metal Industries, Ltd. Method of piercing and manufacturing seamless tubes
AU603650B2 (en) * 1987-03-27 1990-11-22 Sumitomo Metal Industries Ltd. Method of piercing and manufacturing seamless tubes
DE4140948A1 (de) * 1991-12-12 1993-06-17 Schwager Aribert Prof Dr Ing H Verfahren zur herstellung rohrfoermiger teile
US5649440A (en) * 1994-11-17 1997-07-22 Mannesmann Aktiengesellschaft Method for calibration of assel rollers
EP0754503A1 (fr) * 1995-01-10 1997-01-22 Sumitomo Metal Industries, Ltd. Procede et appareil pour obtenir par per age des tuyaux metalliques sans soudure
US5713234A (en) * 1995-01-10 1998-02-03 Sumitomo Metal Industries, Ltd. Piercing-rolling method and piercing-rolling apparatus for seamless tubes
EP0754503A4 (fr) * 1995-01-10 1999-02-10 Sumitomo Metal Ind Procede et appareil pour obtenir par per age des tuyaux metalliques sans soudure
US20090113970A1 (en) * 2005-06-16 2009-05-07 V & M Deutschland Gmbh Method Of Making A Seamless Hollow Body From Steel
US8316680B2 (en) * 2005-06-16 2012-11-27 V&M Deutschland Gmbh Method of making a seamless hollow body from steel
WO2020224758A1 (fr) 2019-05-06 2020-11-12 Vallourec Deutschland Gmbh Procédé et appareil de détermination d'un angle de torsion lors d'une opération de laminage
CN113766979A (zh) * 2019-05-06 2021-12-07 瓦卢莱克德国有限公司 轧制操作过程中确定扭转角的方法和设备
CN113680823A (zh) * 2021-08-31 2021-11-23 攀钢集团研究院有限公司 一种无缝钢管穿孔机及其顶头
CN113680823B (zh) * 2021-08-31 2024-03-12 攀钢集团研究院有限公司 一种无缝钢管穿孔机及其顶头

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Publication number Publication date
DE2054541A1 (de) 1971-05-19
GB1320035A (en) 1973-06-13
BE758174A (fr) 1971-04-01
CA919958A (en) 1973-01-30
FR2068994A5 (fr) 1971-09-03

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