PROCESS FOR PRODUCING SEAMLESS PIPE AND CLEANING EQUIPMENT
    4.
    发明公开
    PROCESS FOR PRODUCING SEAMLESS PIPE AND CLEANING EQUIPMENT 有权
    用于生产无缝管及清洗设备

    公开(公告)号:EP1854561A4

    公开(公告)日:2009-01-07

    申请号:EP06714266

    申请日:2006-02-22

    摘要: This invention provides a process for producing a seamless pipe while effectively suppressing carburizing which occurs in a seamless pipe without affecting the operation. The production process comprises the steps of cleaning a transfer device disposed between a lubricant coating device (7), which is disposed at least in the step of transferring a mandrel bar (B), and a mandrel mill (8) on its inlet side, cleaning the mandrel bar (B) subjected to stretch rolling on the upstream side of the lubricant coating device (7), and coating a nongraphitic lubricant onto the mandrel bar (B) by the lubricant coating device (7). In the production of the seamless pipe, the transfer device and the mandrel bar (B) are washed so as to satisfy formulae (1): 0.08 × C1 + 0.05 × C2 ≤ 3 and (2): 3 ≤ C1 + C2 ≤ 50 wherein C2 represents the amount of graphite deposited on the surface of the mandrel bar (B) before stretch rolling, g/m2, and C1 represents the content of carbon in an organic binder in the lubricant, g/m2.

    PROCESS FOR PRODUCING SEAMLESS STEEL PIPE
    5.
    发明公开
    PROCESS FOR PRODUCING SEAMLESS STEEL PIPE 有权
    VERFAHREN ZUR HERSTELLUNG EINES NAHTLOSEN STAHLROHRS

    公开(公告)号:EP1775038A4

    公开(公告)日:2008-03-19

    申请号:EP05751261

    申请日:2005-06-15

    摘要: A process for producing a seamless steel pipe, in which the occurrence of inner surface flaw in the pipe can be reduced through lowering of the friction coefficient at draw rolling by means of a mandrel mill. At the draw rolling of hollow stock pipe, a lubricant composed mainly of at least one of graphite and mica is applied to the surface of mandrel bar, and further a lubricant composed mainly of a borate of monovalent alkali metal is fed onto the inner surface of hollow stock pipe, satisfying the following requirements (a) to (d). (a) The temperature of inner surface of stock pipe immediately after the completion of piercing is set for >= 1150˚C, and the time from the completion of piercing to feeding of the lubricant composed mainly of a borate of monovalent alkali metal, or the time from the completion of descaling to feeding of the lubricant is set for 5 to 60 sec. (b) The temperature of inner surface of stock pipe during the feeding of the lubricant composed mainly of a borate of monovalent alkali metal is set for >= 1100˚C. (c) The time from the feeding of the lubricant composed mainly of a borate of monovalent alkali metal to the initiation of draw rolling is set for >= 10 sec. (d) The temperature of inner surface of stock pipe immediately before the draw rolling is set so as to range from 1000˚ to 1170˚C.

    摘要翻译: 本发明提供一种无缝钢管的制造方法,其中,通过利用芯棒式无缝管轧机降低拉伸轧制时的摩擦系数,从而能够降低管内发生内表面瑕疵。 在中空管材的拉伸中,将主要由石墨和云母中的至少一种构成的润滑剂施加到芯棒的表面上,并且进一步将主要由一价碱金属的硼酸盐组成的润滑剂供给到芯棒的内表面 中空管材,满足下列(a)至(d)的要求。 (a)刚完成穿孔后的接头管内表面的温度设定为> = 1150℃,从穿孔完成到主要由一价碱金属硼酸盐构成的润滑剂进料的时间,或 从除垢完成到润滑剂供给的时间为5〜60秒。 (b)供给主要由一价碱金属硼酸盐构成的润滑剂时,管坯内表面的温度设定为> 1100℃。 (c)从主要由一价碱金属的硼酸盐组成的润滑剂的供给到拉伸开始的时间被设定为> 10秒。 (d)将即将进行拉伸轧制之前的原料管内表面的温度设定为1000〜1170℃的范围。

    Cr-PLATED MADNREL BAR FOR MANUFACTURING HOT SEAMLESS TUBE AND METHOD OF MANUFACTURING THE SAME
    6.
    发明公开
    Cr-PLATED MADNREL BAR FOR MANUFACTURING HOT SEAMLESS TUBE AND METHOD OF MANUFACTURING THE SAME 有权
    CHROME DORN ROD的用于生产热无缝管及方法生产同样

    公开(公告)号:EP1637245A4

    公开(公告)日:2007-04-18

    申请号:EP04745541

    申请日:2004-06-03

    IPC分类号: B21B25/00

    CPC分类号: B21B25/00

    摘要: A Cr-plated mandrel bar for manufacturing a hot seamless tube and a method of manufacturing the mandrel bar, the mandrel bar wherein since the maximum depths (Rv) thereof in the axial and circumferential directions are specified together with average centerline roughnesses (Ra) in the axial and circumferential directions and the maximum heights (Rp) in the axial and circumferential directions are limited, seizure and other surface defect is hard to occur on the mandrel bar during the drawing of a mandrel mill to remarkably increase the useful life thereof so as to remarkably reduce tool cost. Also, the mandrel bar can largely contribute to the improvement in quality of the inner surface of the hot seamless tube rolled by the mandrel mill. The method can efficiently manufacture the Cr-plated mandrel bar for manufacturing the hot seamless tube.

    METHOD FOR HOT WORKING OF Cr-CONTAINING STEEL
    10.
    发明公开
    METHOD FOR HOT WORKING OF Cr-CONTAINING STEEL 有权
    方法CR-含铜钢温变形

    公开(公告)号:EP1795274A4

    公开(公告)日:2009-03-18

    申请号:EP04770813

    申请日:2004-07-20

    摘要: A method for the hot working of a Cr-containing steel, which comprises holding a newly formed surface of the Cr-containing steel in a steam atmosphere, to thereby form an oxidized scale containing FeO, and then carrying out a subsequent hot working. More specifically, a method for producing a seamless steal pipe which comprises supplying a moisture to the inside of a raw hollow pipe prepared by piercing, to hold the newly formed inner surface of the raw hollow pipe in a steam atmosphere and thereby form an oxidized scale containing FeO, and then carrying out the subsequent drawing. The method allows, by the use of a simple and easy operation method and a simple device, the reduction of the surface defects being caused after a hot working, resulting in markedly prolonging the life of a tool used therein, which contributes greatly to the efficient production of a Cr-containing steel containing 5 to 18 % of Cr being in increasing demand.