公开(公告)号：US20050058851A1

公开(公告)日：2005-03-17

申请号：US10662722

申请日：2003-09-15

申请人： Gaylord Smith ,  Brian Baker ,  Michael Fahrmann ,  Mark Harper

发明人： Gaylord Smith ,  Brian Baker ,  Michael Fahrmann ,  Mark Harper

IPC分类号： B21C23/22 ,  B21C37/06 ,  B21C37/15 ,  B22F3/16 ,  B22F7/08 ,  B23K9/00 ,  B23K35/30 ,  C10G9/20 ,  F16L9/02 ,  B32B15/18 ,  B32B1/08

CPC分类号： B22F3/162 ,  B21C23/22 ,  B21C33/004 ,  B21C37/06 ,  B21C37/154 ,  B22F7/08 ,  B22F2003/208 ,  B22F2009/041 ,  B22F2998/00 ,  B22F2998/10 ,  B23K9/0026 ,  B23K35/308 ,  B23K35/3086 ,  C10G9/203 ,  F16L9/02 ,  Y10T428/12937 ,  Y10T428/12965 ,  Y10T428/12979 ,  B22F9/04 ,  B22F3/20 ,  B22F3/16

摘要： A process for making a composite tube uniquely suited for use in ethylene pyrolysis furnaces wherein the tube comprises an outer shell made from a wrought or cast Fe—Ni—Cr heat resistant alloy and an inner core made from INCOLOY® alloy MA956 powder. The outer shell and powder core are heated and simultaneously extruded to form a composite tube. The process is carried out at temperature, and time at temperature, preferably less than 1200° C. so as to prevent recrystalization of the very fine grain structure in the alloy MA956. This un-recrystalized fine grain structure permits pilgering and/or cold drawing of the extruded composite tube to final size. The composite tube provided by the present invention is uniquely suited for use in the petrochemical and chemical process industries, so as to increase the efficiency and productivity of their respective processes. The thin core layer of alloy MA956 provides high resistance to carburization and coke formation heretofore caused by the hydrocarbon feedstock flowing through the composite tube, while the outer shell of Fe—Ni—Cr heat resistant alloy provides overall strength and rigidity to the tube. The use of the outer shell in the composite tube also solves the joining problem heretofore encountered in joining alloy MA956. A root pass or passes using an alloy MA956 filler metal followed by overlay welding passes using a filler metal compatible with the heat resistant alloy, such as INCONEL alloy 617 or FM 25/35, joins the outer shells of adjoining composite tubes and, thus, solves the welding problem.

摘要翻译： 一种制造独特地适用于乙烯热解炉的复合管的方法，其中管包括由锻造或铸造的Fe-Ni-Cr耐热合金制成的外壳和由INCOLOY合金MA956粉末制成的内芯。 将外壳和粉末芯加热并同时挤出以形成复合管。 该过程在温度和时间在温度下进行，优选低于1200℃，以防止合金MA956中极细晶粒结构的再结晶。 这种未重结晶的细晶粒结构允许将挤出的复合管的拉拔和/或拉伸成最终尺寸。 本发明提供的复合管独特地适用于石化和化工过程工业，从而提高其各自工艺的效率和生产率。 合金MA956的薄芯层对于渗透复合管的烃原料造成的渗碳和焦炭形成具有高的抵抗力，而Fe-Ni-Cr耐热合金的外壳则提供了对管的整体强度和刚性。 在复合管中使用外壳也解决了在接合合金MA956中遇到的连接问题。 使用合金MA956填充金属进行通过或通过，然后使用与耐热合金（例如INCONEL合金617或FM 25/35）相容的填充金属进行覆盖焊接，连接相邻复合管的外壳， 解决焊接问题。