量块检定数据自动化处理方法探讨

<正>众所周知,根据JJG146-2011《量块检定规程》,量块的主要检定参数有量块长度、量块长度变动量和长度年稳定度,数据处理量极其庞大。为了提高量块检定的质量和效率,我们必须使量块检定数据数字化,把复杂的数据处理交给计算机来做。对于接触式干涉仪、光学计和测长机等传统的量块检定光学设备来说,量块检定数据数字化的方法就     

《JJG146-2003量块检定规程》执行中存在的问题

量块长度稳定度是衡量量块质量的一个重要指标,它的好坏将直接影响量块使用尺寸的准确度.针对,对工厂一级量块检定单位在检定量块的长度稳定度时存在的问题进行了分析并提出建议.     

基于LabVIEW的大尺寸量块检定系统的设计与实现

利用LabVIEW开发大尺寸量块检定系统,并引入无线通讯模块和牛顿插值函数,提高了量块检定工作的工作效率和测量数据的准确度,实现了量块长度参数采集及处理的自动化。系统采用模块化设计思路,具有很强的可扩展性。     

比较法测量量块长度的误差分析

新量块检定规程已颁布实施，３等及以下各等级量块的中心长度测量仍采用比较的方法，本文试图通过对比较法测量量块长度的误差来源进行分析，并导出量块长度测量误差计算的一般方法。     

0.5m～100mm 3等量块检定温度控制的分析

在量块检定中,检定环境温度对检定结果影响很大,检定温度的控制是对检定数据可信性的重要保证。本文通过分析温度对量块中心长度不确定度的影响,从而计算出检定时温度控制的范围。     

长度计量基础知识讲座(四)

量块是长度计量中最基本、也是使用最为广泛的实物量具之一。在长度计量检定或校准中,通常将量块作为计量标准器具,对长度计量器具的示值误差进行检定、校准或赋值。在几何量精密测量或精密机械加工中也有直接使用量块测量或作为加工时的尺寸定位。长度计量基准通过各等级的量块将长度量值传递至工作计量器具,直至机械零件的尺寸。因此,量块是长度计量中最重要的计量器具之一。     

接触式干涉仪工作台平面度在量块长度测量中引入误差的探讨

通过JJG 101-2004《接触式干涉仪》和JJG146-2011《量块》检定规程,本文探讨了接触式干涉仪工作台平面度在量块长度测量中的引入误差,结果显示使用接触式干涉检定量块长度时,在极端条件下,工作台平面度引入的误差较大,可能会影响量块的合格评定。     

量块等级对应关系及量块长度偏差分析

阐述量块“等”“级”的对应关系及量块长度偏差与测量不确定度的关系,说明量块检定规程在检定和量值传递中的重要作用。     

量块规程宣贯培训班开班

本刊讯1998年6月22－25日，首期JJG146一94《量块国家计量检定规程》宣贯培训班在四川省成都市举行，来自部分省、市、自治区计量检定机构和部分企业的33名学员参加。第二期培训班也于8月4－7日在山东青岛举行。该培训班为全国几何具长度计量技术委员会主办，由量块计量专家进行主讲。培训中讲解了量块检定规程JJG146－W及其最新的修改内容，对长度基准和稳频激光器的基本概念进行了介绍，介绍了高等级量块检定中常用的空气折射率修正公式的最新发展。培训班的重点内容是量块检定中的测量不确定度分析和计算。由于国家计量检定规程编写的…     

采用电脑量块比较仪对0.5～100mm三等量块中心长度测量结果的不确定度的评定

依据JJG 146-2003<量块>检定规程,采用比较测量法,即以二等量块为计量标准器,以电脑量块比较仪为主要配套设备,检定三等量块中心长度为例,进行其测量不确定度的评定.     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to