陕京输气管道弯管尺寸极限偏差探讨

陕京输气管道用的弯管在力学性能与尺寸极限偏差上是体现其达到90年代国际先进水平的两个主要方面。在分析了国内外有关弯管标准的现状,又参照国内有关标准及国际上通用的美国管件标准后,结合我国所用DN650 X60直缝管试制弯管的经验,制订了适用于我国陕京管道工程的弯管技术条件,其尺寸极限偏差值基本达到或超过了美国管件标准MSS SP75-1993和ASME/ANSIB16.9-1993。成品弯管尺寸极限偏差基本达到技术条件要求,满足了施工现场弯管对号入座,不切割、不校圆、不强力组装的要求。建议修订现有弯管标准,制定适合我国现状的先进的弯管或管件技术标准。

Probing into deviation of dimension limit of bend used in Shanjing gas pipeline

The mechanical property and bend's dimension limit deviation used in Shanjing gas pipeline are the two major aspects representing 90's international advanced level of the pipeline. By analyzing domestic present situation on bend standards, making reference to domestic relative standards and applicable US fitting standards internationally as well as combining with the experience in making bend with DN 650 X60 longitudinally-welded pipe, we work out our specification for bend applicable for Shanjing gas pipeline pro- ject. The dimension limit deviation value of the bend reaches or exceeds US fitting standard MSS SP75 -1993 and ASME/ANSI B 16. 9 - 1993 generally. The dimension limit deviation of bend product reaches the requirement of specification basically,which satisfies the requirements of matching fitting, non cutting, non roundness checking and non forced assembling. It is recommended to revise the present bend standard and work out advanced bend and fitting specifications suitable for our country's present situation.