高频焊管机组刮外毛刺机构的改进

在高频焊管生产中，刮屑时刮刀的快速升降通常采用气路系统控制，存在结构复杂、维修不便，易锈蚀，损坏打刀等缺点，改进后的刮刀升降采用凸轮机构来实现，结构简单，成本低，操作方便。     

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放空管路水力计算是天然气集输工程设计中一个令人极感兴趣，却又常常使人困惑的问题。高计天然气通过管路放空属非稳定流动，放空过程要经历壅塞流、临界流、亚音速流三种状态。放空管路的特征对气体流以及影响极大。其摩阻作用不容忽视。运用工程流体力学基础理论，结合工程实际，提出一种求解新方法，即以可压缩流体有摩擦绝热一维流支的范诺方程为基础求天然气瞬时放空量，运用数值积分法求累计放空时间。计算机程序求解迅速准确     

钻杆的惯性摩擦焊接

摩擦焊在美国的专利发布可以追溯到1891年,那时用来描述利用摩擦热连接缆线。接着在欧洲进行了一段时间的研究,德国和英国都有许多的专利发布。1956年,俄罗斯发布了一个将摩擦热用于焊接的专利,这也被视为最早的摩擦焊专利。 20世纪50年代,卡特彼勒研究中心开始研究摩擦焊。他们设想利用储存在一个惯性物体中的能量来提供焊接所需的热量。这项工作最后导致1967年最早的惯性摩擦焊机专利的诞生。惯性摩擦焊是一个金属结构重组的过程,很象锻造。它跟     

Plane flow model of non-Newtonian turbulent stratified flow in wells and pipes

Economical and efficient long-distance oil and natural gas pipe transportation technologies are greatly demanded. Nowadays, oil and gas mixed transportation is gradually put into practice and researchers pay much attention on the theories of two-phase flow in pipe. Methods that can efficiently solve problems of this field are being put forward including hydraulic approach. A new approach, the Rotatable Coordinate Axis, is proposed in this paper. It is used to study the hydraulic characters of two-phase stratified flow in pipe. Based on the new method, the plane flow model for stratified turbulent flow in pipe is built. Then, we can obtain the analytic formulas of velocity, discharge etc. in wells and pipes by this model. To prove the theory of the plane flow model, experiments of aeration in stratified pipe is conducted with the aeration experiment device. The experiment data showed that aeration could effectively achieve the resistance reduction in pipeline, which can offer great theory support to the development of oil and natural gas mixed transportation technology.     

高压管网式全淹没二氧化碳灭火系统的设计

笔者结合工程实例,全面地阐述了高压管网式全淹没二氧化碳灭火系统的灭火机理、适用范围、组成、启动方式、技术性能、动作程序、安装要求、标志、相关专业设计要求、设计程序、设计要点。     

塔里木沙漠管道补口技术

本文以塔中四一轮南沙漠管线工程为实例，介绍了补回材料一热收缩套的结构、现、格．详述了现场补口施工工艺过程．并强调了在沙漠环境下热收缩套补口施工的注意事项。与用石油沥青补口相比，用收缩套补口具有操作简单、劳动强度低和补口质量易于保证等优点。     

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围绕热辐射、噪声和扩散详述了天然气放空立管的基本设计原则和方法。按照放空气体管口流速为０．５倍音速设计放空立管直径，根据火炬热辐射强度对不同环境的影响设计放空立管高度。     

The effect of material difference and flange nominal size on the sealing performance of new gasketless flanges

This paper deals with a new seal system between flange joints without using a gasket. This gasketless flange includes a groove and an annular lip that is machined in one of the flange rings which when removed being in contact with the other flange to form a seal line when the flanges are assembled. In this study, firstly, fundamental dimensions are examined for unplasticized polyvinyl chloride (PVC-U JIS) to obtain the best sealing performance. Then, the effects of material difference and flange nominal size upon the sealing performance of the new gasketless flange are investigated for two types of materials, 0.25% carbon steel (S25C JIS) and PVC-U. It is found that the critical internal pressure at which leakage appears is mainly controlled by the maximum stress at the annular lip for each material even if the flange nominal sizes are different. The gasketless flange made by PVC-U shows the higher critical internal pressure compared with the case of S25C if the same clamping forces are applied. The effect of stress relaxation for PVC-U on the sealing performance is also considered. Then, it may be concluded that this PVC-U gasketless flange as well as S25C has good sealing performance.     

梅山精矿管道输送试验研究

本文根据梅山铁矿铁精矿浆管道输送试验实测数据，通过分析、归纳得出了计算水力坡度和临界流速的数学模型。本文同时还对最佳输送浓度进行了分析。     

别墅区室外管网工程施工管理探讨——以厦门某别墅区为例

室外管网施工作为工程结束前最重要的一部分,工序安排、交叉施工和协调事项等等都是工程施工能否顺利进行的影响因素。本文以厦门某别墅区室外管网工程施工为例,针对室外管网工程施工特点,总结多年的施工组织管理经验,探讨如何对别墅区室外管网工程进行有效的施工管理。