锯材指接自动涂胶设备的研制与应用

针对锯材指接涂胶过程中存在的涂胶不均、效率低、涂胶辊易磨损等问题，提出一种锯材指接自动涂胶的方法。基于PLC(programmable logic controller，可编程逻辑控制器)，采用自动化检测技术，经过模块化设计，设计了一种新型自动涂胶设备，并进行了锯材指接自动涂胶试验。工厂化试验结果表明：自动涂料设备以200根/30 min的速度工作时，自动1次循环涂胶的合格率可达到97%及以上，且随时间逐渐提高，整个过程中设备无故障；自动2次循环涂胶时，在60—90 min、90—120 min内设备各出现1次故障，合格率均达95%及以上，无故障工作时间内自动2次循环涂胶的合格率可达到98%及以上，而人工涂胶合格率在90%以下。试验表明该自动涂胶设备能够实现快速自动涂胶，保证锯材指接涂胶质量，提高锯材指接涂胶的自动化程度，适合应用于锯材指接的工业化生产。     

舰船设备冲击试验机研究进展

简单回顾了各国海军舰船设备冲击试验研究的发展历史，并介绍了考核舰船设备抗冲击破坏能力的主要试验手段，如舰艇水下爆炸试验、虚拟冲击试验以及冲击试验机模拟冲击试验。详细分析了世界各主要国家的冲击试验机发展现状，得出冲击试验机在三个方面的发展趋势：1）模拟实际冲击过程，如模拟水下爆炸过程中的第一次冲击波和气泡脉动效应的双波冲击试验机；2）能够试验重型设备，向超大规模试验方向发展；3）精确波形控制，利用现代技术增强试验过程的可重复性。     

制冷设备的检漏

制冷系统在装配完毕或放掉制冷剂检修完毕后,都要进行气密性试验,这是检查装配和检修质量的重要手段。气密性试验又称检漏。是确定系统在承压或真空状态下是否有泄漏的一项试验。它在系统吹污后进行。一般有压力试漏、真空试漏和制冷剂试漏三个程序。压力试漏是将高压     

一种新型空气处理机组的研制与试验

本文介绍了一种采用机、电、仪一体化的带微机监控的全自动节能空气处理机组样机的部分功能,通过试验,得出新机组比常规机组节能40％的显著效果。     

光测设备天文标校单项误差分离算法

为实现船载光测设备的经常化检查校准,针对影响天文标校工作成败的诸关键要素,在理论分析的基础上进行了试验研究.首先对天文标校方法硬件原理、软件组成、工作流程进行介绍,然后重点对设备误差分离算法进行分析,首次提出了基于奇异值分解的误差方程解算方法,最后给出了试验研究的一组典型数据.标校试验结果表明:该标校方法可以实现8项单项误差的成功分离,关键项多次标校数据重复性小于等于±1",使设备实际测角精度提高1倍,并优于常规标校的设备精度.     

设备双行布置从至表试验法的改进

针对设备双行布置从至表试验法存在的缺陷,提出了改进的从至表试验法.改进后的从至表试验法根据双行设备布置图的特点,运用从至数之和大的居中间区域,小的靠两端区域和关系密切的设备尽可能的近邻,不密切的远离,两条原则结合,用有限的几次试验就可获得比较满意的近似最优解.该方法简便宜行、便于掌握,优化效果良好.     

IEC 62368-1:2018与现行国标中结构要求的比较分析

本文从机械强度试验、设备的稳定性和防触电结构要求三个方面总结了IEC 62368-1:2018与GB 8898-2011/GB 4943.1-2011之间的差异,并对差异进行了分析,为设计、生产、检测等相关人员能够更好理解IEC 62368-1:2018中关于设备结构的要求,并将相关要求导入到产品中,以及实施相关检测具有指导意义.     

改造M2拍摄机进行彩色缩微拍摄试验的尝试

为了解决彩色珍贵文献长期保存和保护的问题,进行彩色拍摄的试验工作。在目前无法添置彩色拍摄机的情况下,对现有的黑白缩微拍摄机进行了局部的改造,顺利完成了彩色文献缩微的试验工作。     

空间环境模拟设备穿透式隔振系统性能仿真分析北大核心CSCD

某些航天器产品,特别是光学载荷在进行空间环境试验时对试验环境的振动指标通常有严格的要求,需要采用隔振系统。而空间环境模拟设备内部特殊的真空、低温环境,对隔振系统的设计提出了特殊的要求。本文给出了一种穿透式隔振系统的总体设计方案,并采用整体模态分析、系统振幅分析方法对隔振系统的性能进行了分析计算。结果表明,隔振系统能够满足在1~2 Hz频段内,3个方向的振动位移幅值均≤0.4μm,具有良好的低频隔振性能,能够满足航天器产品空间环境模拟试验时对振动的隔离需求。     

浅谈温湿度试验设备的计量

温湿度试验设备一般指带有湿热功能的高低温试验箱,它们为试验样品提供模拟的温湿度试验环境,是目前试验样品进行环境试验的主要试验设备。而温湿度试验箱提供的温湿度是否精确,试验箱的性能指标是否满足试验样品的需求,则需要有资质的计量检定机构对温湿度试验箱进行计量检定。本文结合我所温湿度试验箱计量过程中的经验总结,浅谈温湿度试验设备的计量。     

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.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

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.