金属风管咬口机的使用与管理

金属风管咬口机的使用与管理李兴武（陕西省安装机械厂西安７１００６１）随着建筑安装施工技术的不断发展，通民空调工程的施工状况已有较大改观。金属风管与管件制作已由传统的手工敲打为主辅以简单机具，发展为以专用设备为主并辅以手工装配的方式，不仅减轻了劳动强度...     

用电子表格辅助制作风管的天圆地方

文章介绍了如何利用Excel电子表格软件自动计算不同规格的“天圆地方”的放样参数。着重讲述了从公式推导到Excel内部函数的编写及电子表格的具体制作与应用     

洁净风管制作的环境控制

制作流程:堆放→制作→清洗→冲洗→干燥→封口→成品保洁措施:堆放室:做好防雨、防潮、防火、防盗措施,摆放的镀锌钢板,用塑料布盖好,严禁损伤;缓冲室:为了防止沾染污物,设置长2m×宽0.6m×高0.75m的钢管平台,铺厚度3mm的夹布橡皮板;     

复合玻纤板风管的制作与安装

复合玻璃纤维板,简称玻纤板.这种风管具有消声效果好、不燃烧、不腐蚀、绝热、保温好,且质量轻等优点.被广泛地应用在无凝结水、输送气体的通风空调工程中.     

《非金属风管制作与安装》国家标准图集的介绍

本文叙述了国家标准设计图集《非金属风管制作与安装》的编制背景、适用范围、编制内容、图集特点和使用说明等,着重介绍了各种非金属风管、通用附件的制作工艺,以及风管安装做法和装配式支吊架的常用类型选型,为工程技术人员应用图集提供指导。     

用扭角计测定扭转机械性能的方法

扭转试验能够客观地反映材料(脆性或塑性)的各种机械性能指标,是测试金属机械性能的重要方法之一。飞机k有许多属于产生扭转变形的构件,如发动机的转动轴、承载的卷弹簧、螺旋桨等。设计这些构件时所选用的材料,必须测出扭转时的各种机械性能数字指标(G、τ、τ_(0·3)、τ_b、t_K),提供于算构件强度的准确数值,才能使设计的构件安全可靠。用千分表扭角计测定扭转机械性能时比用马腾式光学引伸计效率高。现将测试情况介绍如下。 一、试验材料、机器和仪器 试验所用材料列入表1;所用机器为K-50型扭转试验机(选用50公斤-米表盘);试样受扭时用的测量仪器——千分表及扭角的测定如图1、2。     

用角位置信号估计角速度方法的研究

用SIMULINK语言建立光电码盘的仿真模型,分析码盘测速值中包含噪声的原因及其对系统性能的影响。并提供了一种速度观测器以估计电机的瞬时速度。并用仿真结果证明以该观测器的输出构成的闭环系统对系统性能的影响。     

浅谈某高层建筑通风空调工程风管系统的制作和安装

本文介绍了某高层商厦中央空调工程风管系统的制作和安装情况,以及在通风空调风管的制作、安装方面采用的新工艺、新技术和在安装过程中的一些体会。     

改进创新的带供氧和防移位功能的咬口垫

供氧功能：胃镜是经病人口腔置入,用以检查和治疗胃、食道疾病的内窥镜。它是现代直观诊断上消化道疾病中较先进且较贵重的仪器之一。在胃镜操作中．普通的咬口垫,塞到病人口中,然后插入内窥镜,内窥镜的导管插入’后,咬口垫口部很大一部份会被档住,这样气体不畅通。     

新规程实施后手术室洁净空调系统的风管制作与安装

探讨手术室洁净空调系统风管制作的流程,探讨新规程实施后在洁净空调系统方面需作如何改进以适应新规程.     

通风空调风管的制安技术

本文结合空调通风工程的具体工程实例,介绍了风管的制作、安装技术及常见的风管制安质量问题与相应的防治措施.     

螺旋风管制作及其无法蓝连接工艺

文章简要介绍了螺旋风管的加工制作及特点，并对螺旋风管的无法蓝连接工艺进行了全面分析。     

基于SCADA数据的风机叶片结冰检测方法

针对工作在寒冷地区的风机易出现的叶片结冰现象,提出一种基于SCADA数据的风机叶片结冰检测方法。根据叶片结冰会增大发电机的功率损耗,选择风速与网侧有功功率2个变量,利用主成分分析技术构造对叶片结冰敏感的风速与网侧有功功率在非主成分方向投影特征,通过选择最优阈值使逻辑回归分类器适用于不平衡分类,可以实现风机叶片结冰检测自动化与智能化。通过中国工业大数据创新竞赛数据验证了该方法的有效性。     

高温高压蒸汽管冷紧口的安装

《电力建设施工及验收技术规范》“管道篇”(DL50 31- 94 )第 5.1.13( 1)～ ( 4 )和《火力发电厂汽水管道设计技术规定》(DLGJ2 3- 81)第 4 .33～ 4 .35条都规定了对于蠕变条件下工作的管道应进行冷紧 ,当热伸长较大和需要减小对设备的推力和力矩时 ,宜进行冷紧。火力发电厂中 ,由锅炉过热器集箱出口至汽轮机之间的高温高压主蒸汽管道就属于这种状况。文章对冷紧口的预留与安装及管段的安装作了详细的介绍。     

Satellite Cloud-Derived Wind Inversion Algorithm Using GPU

Cloud-derived wind refers to the wind field data product reversely derived through satellite remote sensing cloud images. Satellite cloud-derived wind inversion has the characteristics of large scale, computationally intensive and long time. The most widely used cloud-derived serial--tracer cloud tracking method is the maximum cross-correlation coefficient (MCC) method. In order to overcome the efficiency bottleneck of the cloud-derived serial MCC algorithm, we proposed a parallel cloud-derived wind inversion algorithm based on GPU framework in this paper, according to the characteristics of independence between each wind vector calculation. In this algorithm, each iteration is considered as a thread of GPU cores, and each thread block array of GPU allocates n*32 threads, and the many thread blocks are allocated to the thread grid. The parameters of the algorithm are passed from CPU to GPU global memory and the storage spaces are previously created on the GPU device before the functions of algorithm are executed. The test results of multiple sets of different inversion models on the NVIDIA Geforce GT and the 4-core 8-thread Core i7-3770 CPU show that the algorithm significantly improves the inversion efficiency. The acceleration ratio is up to 112, and the parallel experiment acceleration ratio is also impressive.     

Optimization of Resin Infusion Processing for Composite Pipe Key-Part and K/T Type Joints Using Vacuum-Assisted Resin Transfer Molding

In present study, the optimization injection processes for manufacturing the composite pipe key-part and K/T type joints in vacuum-assisted resin transfer molding (VARTM) were determined by estimating the filling time and flow front shape of four kinds of injection methods. Validity of the determined process was proved with the results of a scaling-down composite pipe key-part containing of the carbon fiber four axial fabrics and a steel core with a complex surface. In addition, an expanded-size composite pipe part was also produced to further estimate the effective of the determined injection process. Moreover, the resin injection method for producing the K/T type joints via VARTM was also optimized with the simulation method, and then manufactured on a special integrated mould by the determined injection process. The flow front pattern and filling time of the experiments show good agreement with that from simulation. Cross-section images of the cured composite pipe and K/T type joints parts prove the validity of the optimized injection process, which verify the efficiency of simulation method in obtaining a suitable injection process of VARTM.     

Short-Term Wind Speed Forecast Using Measurements From Multiple Turbines in A Wind Farm

Turbine operations in a wind farm benefit from an understanding of the near-ground behavior of wind speeds. This article describes a probabilistic spatial-temporal model for analyzing local wind fields. Our model is constructed based on measurements taken from a large number of turbines in a wind farm, as opposed to aggregating the data into a single time-series. The model incorporates both temporal and spatial characteristics of wind speed data: in addition to using a time epoch mechanism to model temporal nonstationarity, our model identifies an informative neighborhood of turbines that are spatially related, and consequently, constructs an ensemble-like predictor using the data associated with the neighboring turbines. Using actual wind data measured at 200 wind turbines in a wind farm, we found that the two modeling elements benefit short-term wind speed forecasts. We also investigate the use of regime switching to account for the effect of wind direction and the use of geostrophic wind to account for the effects of meteorologic factors other than wind. These at best provide a small performance boost to speed forecast.     

Assessment of Pipe Defects Using a Constraint-Modified Failure Assessment Diagram

In this study, the failure assessment diagram (FAD) is constraint modified using the assumption that the constraint T stress is proportional to the non-dimensional loading. The constraint-modified FAD has been used to compute safety factors associated with spherical and elliptic defects and a long notch. The results were compared to the classical approach, indicating the possibility of a reduction of conservatism. In addition, the use of domain constraint-modified FAD indicates that in some cases, increases in fracture toughness due to the loss of constraint lead to the use of limit analysis rather than an elasto-plastic fracture mechanics approach.

     

电阻热效应对力式微固态测风传感器测量精度的影响

本文就电阻热效应对基于风的拖动力原理的微型固态测风传感器测量精度的影响进行了研究.微型固态测风传感器通过溅射在悬梁上的铂电阻测量悬梁弯曲应变来获得风速信息和简单的风向信息.风吹过铂电阻时,除了应变引起电阻阻值变化外,由于热传导、对流、辐射等热效应,其阻值也会随着风速的变化而变化.当热效应引起的电阻的变化趋势和应变引起的电阻变化趋势相反时,传感器的输出先减小后增大,风速测量产生较大误差.文中对两种铂电阻在悬梁上的放置连接方式的传感器进行了理论分析,通过对利用MEMS工艺制作的两种传感器的测试,证实理论分析与实验结果相符.