文章介绍了国家标准GB/T 2624--2006<用安装在圆形截面管道中的差压装置测量满管流体流量>的主要变化.分析和讨论了在贯彻、实施这些规定时存在的突出问题及各种不同的应对办法,并提出几点建议.

当今世界已经进入信息时代,信息技术成为推动科学技术和国民经济高速发展的关键技术.著名科学家钱学森早就明确指出:"信息技术包括测量技术,计算机技术和通信技术.测量技术是关键和基础."在这里,钱老不仅界定了信息技术的内涵,而且也突出明确强调了测量(计量)技术的重要性.

<正>一、测量仪器仪表的重要性当今世界已经进入信息时代。信息技术成为推动科学技术和国民经济高速发展的关键技术。著名科学家钱学森早就明确指出:信息技术包括测量技术、计算机技术和通信技术。测量技术是关键和基础。在这里,钱老不仅界定了信息技术的内涵,还突出明确强调了测量(计量)技术的重要性。

介绍"国家标准GB/T 2624.2-2006<用安装在圆形截面管道中的差压装置测量满管流体流量>第2部分:孔板"中关于直管段长度规定的变化.分析和讨论了在贯彻、实施这些规定时存在的问题,并提出几点建议.

用实验方法对具有不同的等效直径比β值的V锥流量计的性能(特性)进行评价.流量计的性能是雷诺数和上游干扰的函数.利用水和油作为被测介质,在一个较宽的雷诺数范围内进行实验.在V锥流量计的上游5D、10D和15D处安装有一个闸阀,利用该阀作为扰流件来研究上游速度分布对V锥流量计的影响.具体的作法是在阀的不同开度(如开度为25%、50%、75%和全开)下做实验.根据实验研究可以看出:V锥流量计的流出系数Cd几乎与雷诺数无关.对于β=0.64的V锥流量计流出系数值为0.7256±1.78%,而对于β=0.77的V锥流量计,流出系数值为0.7315±1.9%.如果在V锥流量计的上游10D或更远处装有扰流件,则不会影响流出系数值.如果在V锥流量计的上游5D处安装扰流件,则Cd值的变化约为6%.

There is huge CBM resource in the U.S.A.,and it is estimated that 30 thousand CBM wells will be drilled only in the Rocky Mountainous area in the future 8 or 10 years.However,some of the challenges that CBM producers experience relate to accurate measurement at the wellhead whilst maintaining a low differential pressure across a system and also dealing with wet gas issues in the meter run.This paper introduced the use of differential pressure meters which use a double cone as the primary differential pressure producer.Its typical structure helps the V-cone flow meter have strong ability of flow adjustment,and operate with good accuracy at low DP's.Its unique design on the V-shape column is not only beneficial to the extraction of CBM,but also can prevent CBM wells from cross interference or from CBM gas injecting into the neighbouring wells due to malfunction of a certain valve.The V-cone flow meters have been widely used in the exploitation of CBM in the U.S.A.

This paper discusses and compares the relative signal noise between the V-Cone differential pressure flowmeter and a typical orifice plate differential pressure flowmeter. For this paper, signal noise shall be defined as the fluctuations in the differential pressure signal at a constant flowrate. Users of V-Cones have often commented on the significant drop in signal noise experienced when using a V-Cone instead of a traditional orifice plate. Many times the most noticeable differences were experienced in disturbed flow conditions. This drop in noise allowed the users better signal readings with less damping of the differential pressure transmitter.

V锥体流量计是一种新型的差压式流量计,最初仅由美McCrometer一家公司生产。当流体流经在管道中同轴安装的V形圆锥体时,在其前后两端产生差压。通过测量此差压值就能算出流量值。

V锥体流量计是一种新型的差压式流量计,最初仅由美McCrometer一家公司生产.当流体流经在管道中同轴安装的V形圆锥体时,在其前后两端产生差压.通过测量此差压值就能算出流量值.

To enhance energy metering and to reduce energy consumption it is necessary to replace those flow meters, which have large energy consumption, with new flow measurement technology in the application with large pipe sizes and high flow rates especially. In this paper this issue is discussed theoretically and proved with experimental results. The new principle for flow meter selection is given in the end of this paper.

Flowmeters are the important components of the energy metering apparatus. To implement the latest issued National Standard GB 17167- 2006 "General Principle for Equipping and Managing of the Measuring Instrument of Energy in Organizations of Energy Using", reasonable selection of flowmeters is a key point. The principle of selecting flowmeters and the considerations in design procedures are expounded.

流量仪表是能源计量器具的重要组成部分。为实施最新国家标准GB17167—2006《用能单位能源计量器具配备和管理通则》,流量仪表的合理选型是关键的一环。文章将对流量计的合理选型及应考虑的重要事项予以阐述。

To promote energy saving and use energy efficiently, it is suggested to replace the flowmeters with high energy consumption which were equipped in pipeline system which was characterized as large diameter and flow rate by new type of flow measurement instrument. Thus, it was academically and experimentally studied and demonstrated. Meanwhile, type selection principles for the new type flowmeter were put forward. ①good linearity ; ②high accuracy; ③high flow adjustment ability along with short straight pipe section with no flow regulator; ④small permanent pressure loss and low energy consumption; ⑤well designed with wide measurement range; ⑥self-clean function and designed to allow measurement for the contaminative flow with no filter; ⑦robust against corruption caused by flow, stable performance and no need of moving parts; ⑧minimum overhaule and long life expectancy; ⑨minimum maintenance; ⑩economically feasible and low operation and installation cost. It was confirmed by many domestic and international experience and test results that the V-cone flowmeter can well meet the requirements listed above.

由于V形内锥(VNZ)流量计除具有压损较小,量程比较大及相当强的流动调整能力等主要特点外,它还具有自清扫、自保护和自混合等能力,因此它能更好地满足节能降耗和各种工业计量的要求.文章从理论和实践两方面重点分析和论证了VNZ流量计低压损的特点.为全面作好VNZ流量计的推广应用工作,作者在文末提出了几条建议.

文章介绍了在 Colorado 测试装置上按照美国石油学会新的"石油测量标准手册"第5章第7节"差压式流量测量仪表测试大纲"的要求对维夫(法兰夹装)式 V 形内锥式流量计所作的测试。文章将报告关于这一新的 API 标准的使用(情况)以及为执行这一标准必须要论述的一些观点。文章中介绍了在水装置和气体流量标准装置上对DN50mm 和 DN100mm(2")(4")的维夫式内锥流量计进行测试的结果。在该 API 标准中所提出的非标准(条件)的测试要求将提供关于 V 形内锥式流量计当它进行流体流量测量时具有整流作用的证据。所得出的结论是:按照API5.7,按照所要求的方式测试了流量计生产厂家关于其产品所宣称的各项指标。当实际执行该程序时,有必要作一些修改,文章将论述一些限制的条件与范围。在进行测试时,这些限制已变得很明显。文章将论述、报告关于 V 形内锥流量计不确定度的测试结果。

In order to reduce the power consumption flow meters with low pressure loss should be used.The method for calculating the power consumption of flow meter is introduced.By comparison of two examples and analysis of the operation mechanism for VNZ flow device,the necessity of popularizing VNZ flow meters is presented.

对于高压天然气和液态烃(石油)的贸易来说,流量测量的作用已经公认非常重要.目前有各种新技术被开发出来执行这些流量测量任务,如精确和可靠的超声流量计和科氏力流量计,它们都采用非常高级的计算机软件.然而,目前为环境保护和节能技术的研究与开发,要求在各种不同条件下进行流量测量.为满足这些环保与节能的技术要求,流量测量正变得更加困难和更为重要,成为解决环保与节能难题的关键技术.文章将论述环保与节能工程中的这些流量测量难题,如:为用于车辆尾气排放量测量的流量测量技术;环保化学分析的标准气生产中的流量测量;脉动流流量测量的新基准;极小气体流量的新基准;氢(H2)作为新一代的清洁能源,目前正有许多新技术在开发之中,比如燃料电池,为了要评价燃料电池的性能则需要有测量氢(H2)的新型流量计;目前正在研发一种专门用于测氢流量(气体)的超声流量计,此项研发工作方兴未艾;核电厂的生产规模将进一步扩大,应用和发展核电技术将减少二氧化碳的排放量(它比火电厂排放的CO2要少得多),随着核电生产能力的增加,将提出一系列流量测量要求,文章讨论了用于生产能力扩大后的核电厂的大型超声流量计的校准方法.