王冬雁¹，  宫俊峰²，  胡凤琴³，  张喜艳⁴，  林冰¹
    （1 中国建筑工程总公司技术中心，北京101300；2 北京京能热电股份有限公司，北京100042；3 中国建筑股份有限公司海外事业部工程技术部，北京100300；4 西安建筑科技大学土木工程学院，西安710055）

[摘要] 利用空间几何关系及坐标变换原理，推导出空间焊接节点管管相贯时相贯线平面展开公式。通过该公式的计算，可以准确、方便地绘出相贯线的平面展开图形，利用图形放样或与数控机床连接，可以进行相贯口的切割。文中公式不但用于球节点多管相贯，也可用于管桁架多管相贯。
[关键词] 相贯线；坐标变换；平面展开公式
中图分类号：TU378    文献标识码：A  文章编号：1002-848X(2011) Sl-0857-03

Expand calculating techniques of intersecting lines of multi steel pipes for space welding node
Wang Dongyan¹,  Gong Junfeng²,  Hu Fengqin³,  Zhang Xiyan⁴ ,Lin Bing¹
(1 China State Construction Engrg. Corp.Technical Center, Beijing 101300, China; 2 Beijing Jingneng Thermal Power Co.,Ltd.,Beijing 100042, China; 3 Department of Engineering Technology of China State Construction Engre.  Ltd.  Overseas Operations, Beijing 100300, China; 4 College of Civil Engineering, Xian Univ. of Arch. & Tech., Xian 710055, China)

Abstract: The geometric relationship and coordinate transformation were used to derive the expansion formula of more intersections in a pipe for space welding node. Through the calculation of that formula the plane figure ofintersecting line can be drawn accurately and conveniently. The intersection mouths can be cut through lofting or CNC machine tool. The formula in tlus paper can be used for nodes not only in network structure but also in multi-pipe truss structure.
Keywords: intersecting line; more intersections; expansion formula in the plane