推进农产品工业发展势在必行

本文通过对国内外加工业的现状的比较,指出了我国农产品加工业与国外的差距.提出了促进农产品加工发展的建议.对国内农产品加工业发展有积极的促进作用.     

我国农产品加工业的成就与展望

改革开放30年来,我国农产品加工方面取得突出成就,科技攻关突飞猛进.与世界发达国家的差距越来越小;产品加工业总量快速增长.产业成长快速化,加工企业规模化;农产品加工业由初加工向深加工、专业化转变;农产品加工业的区域发展新格局初步形成,出现了一大批优势农产品加工业产业集群.随着国务院<关于当前稳定农业发展促进农民增收的意见>的实施,我国农产品加工业必将迎来又一个大发展,顺利完成"十一五"规划.     

为汽车零、部件加工业积极提供工艺装备是机床工具行业的战略任务

汽车零部件加工业是组成汽车工业的一个重要产业部。近年来,虽然随着我国轿车工业的发展加大了零、部件加工业技术引进与技术改造的投资力度,但从发展我国汽车工业的要求来衡量,还需进一步加强与加快零、部件加工业的发展,而零、部件加工业的发展又与我国机床工具行业能否及时提供先进的工艺装备密切相关。本文从这个角度出发,扼要分析了汽车零、部件加工业对装备的要求,探讨机床工具行业满足这些要求的对策与措施,及其对机床工具行业本身的影响。     

机械加工技术中数控加工的应用

我国无论在经济方面还是在科学技术研究方面发展速度都在不断加快,随着我国改革的不断深入,我国综合国力水平在不断提升,在一定程度上促进了我国机械加工业的快速发展。机械加工业的发展在一定程度上能够直观反映出我国工业发展水平,机械加工业的发展离不开先进技术的支持。数控技术在机械加工业的应用是机械加工发展的重要标志,数控加工技术建立在计算机控制技术的基础之上,换而言之,数控加工是由计算机控制和管理的。数控加工技术在机械加工技术中的有效应用,在一定程度上有效的提高了机械加工的精确性、加工效率,而且还降低了人力资源的投入,从而减少了生产成本。     

美国肯纳金属公司简介

美国肯纳金属公司简介美国肯纳金属公司（ＫｅｎｎａｍｅｔａｌＩｎｃ．）是世界最著名的硬质合金生产制造公司,也是美国最大的刀具生产制造商。六十年前,肯纳金属公司发明了钨钛碳化物合金,并成功地将这一新发明应用于金属加工业,这种新刀具以切削速度快、使用寿命长...     

美国肯纳金属公司简介

美国肯纳金属公司简介美国肯纳金属公司（ＫｅｎｎａｍｅｔａｌＩｎｃ．）是世界最著名的硬质合金生产制造公司,也是美国最大的刀具生产制造商。六十年前,肯纳金属公司发明了钨钛碳化物合金,并成功地将这一新发明应用于金属加工业,这种新刀具以切削速度快、使用寿命长...     

机械加工技术中数控加工的应用分析

机械加工业作为我国的重工业,强有力地推动着我国国民经济的发展.目前,要想有效地提高我国的机械化水平,就要重视现代计算机技术的作用,将计算机中的数控加工技术引入机械加工中,提高机械设备加工效率,当前数控技术已在机械加工的诸多领域有所运用,其具有精准加工的特点,并有效地提高了机械加工业的经济效益.本文将深入研究数控加工技术...     

金融危机对我国农产品加工业的影响及其发展思路

金融危机对我国农产品加工业的影响表现在我国农产品的价格全面下行、优势农产品出口受阻、乡镇企业和农产品加工业发展困难加、农民工就业困难等方面.金融危机下我国农产品加工业发展思路的关键就是要以科学发展观为统领.围绕现代农业建设、社会主义新农村建设和农民就业增收.因地制宜,发挥优势,科学规划,合理布局.依靠科技.突出大宗和优势农产品加工,提高精深加工程度,做好综合开发利用.转变增长方式,提升产业层次,拓展产业功能,逐步实现由数量增长向质量和效益提高的转变.     

浅析自动化控制技术在机械加工工艺中的应用

自动化控制技术在机械加工业中的发展应用,促进了机械加工业的发展,要想使我国的机械加工工艺能够持续发展进步,就要保证自动化控制技术能够不断地发展创新。本文就对于如何研究发展自动化控制技术并更好地将其运用到机械加工工艺中,并根据在研究中出现的问题进行进一步的分析并提出了相关观点看法,以期可以促进机械加工及自动控制技术的进步和发展。     

钨资源在硬质合金刀具行业中的可持续发展

针对我国钨资源日益紧缺的形势,在硬质合金刀具行业中以刀具的全生命周期为基线,从发展高档硬质合金刀具提升刀具使用性能,提高刀具材料利用率,回收利用废旧刀具材料,研发新刀具材料及推广应用其他刀具材料几个方面来论述减少钨资源消耗的措施,为钨资源在硬质合金刀具行业中的可持续发展提供思路和方法.     

基于氧化锆切削的精密工具市场分析

氧化锆陶瓷这一新型材料在各方面的广泛应用,带来了广阔的加工工具市场前景。目前市场上对氧化锆加工的工具称之为氧化锆瓷块铣刀,这类铣刀其主要材质为硬质合金加金刚石涂层。国内的氧化锆陶瓷切削刀具主要是依靠国外进口来满足国内各行业的加工需求。在我国面临自主创新产业转型阶段,针对市场空缺应运而生一些自主研发、针对性较强的集研发设计于生产销售为一体的企业就成为必要。     

Performance of cryogenically treated tungsten carbide tools in milling operations

This paper describes a study on the effects of cryogenic treatment of tungsten carbide. Cryogenic treatment has been acknowledged by some as a means of extending the tool life of many cutting tool materials, but little is known about the mechanism behind it. Thus far, the only few detailed studies conducted pertain to the cryogenic treatment of tool steels. However, tungsten carbide cutting tools are now in common use in industry. This paper primarily reports and analyses the differences in tool performance between cryogenically treated and untreated tungsten carbide tool inserts during the high-speed milling of medium carbon steel. In addition to dry cutting, machining with coolant was also tested. From the results, it can be seen that cryogenically treated tools exhibit better tool wear resistance than untreated ones. Also, it is evident that the application of coolant during cutting helps to reduce tool wear experienced by the cryogenically treated tools even further. In addition, cryogenically treated tools are found to perform best under a particular set of cutting conditions.     

Design of ultrasonic elliptical vibration cutting system for tungsten heavy alloy

Nanoscale surface roughness of tungsten heavy alloy components is required in the nuclear industry and precision instruments. In this study, a high-performance ultrasonic elliptical vibration cutting (UEVC) system is developed to solve the precision machining problem of tungsten heavy alloy. A new design method of stepped bending vibration horn based on Timoshenko’s theory is first proposed, and its design process is greatly simplified. The arrangement and working principle of piezoelectric transducers on the ultrasonic vibrator using the fifth resonant mode of bending are analyzed to realize the dual-bending vibration modes. A cutting tool is installed at the end of the ultrasonic vibration unit to output the ultrasonic elliptical vibration locus, which is verified by finite element method. The vibration unit can display different three-degree-of-freedom (3-DOF) UEVC characteristics by adjusting the corresponding position of the unit and workpiece. A dual-channel ultrasonic power supply is developed to excite the ultrasonic vibration unit, which makes the UEVC system present the resonant frequency of 41 kHz and the maximum amplitude of 14.2 μm. Different microtopography and surface roughness are obtained by the cutting experiments of tungsten heavy alloy hemispherical workpiece with the UEVC system, which validates the proposed design’s technical capability and provides optimization basis for further improving the machining quality of the curved surface components of tungsten heavy alloy.     

Nouveaux développements dans les outils de coupe en cárbure fritte

Economic and strategic considerations due to the scarcity and cost of metals (tantalum, tungsten, cobalt etc.) together with technological requirements (improved machining properties to increase toughness and wear resistance) require the development of new sintered hard metals. Such materials can be produced by the total or partial replacement of cobalt by iron, nickel or ruthenium, of tungsten by molybdenum or titanium and of tantalum by niobium or hafnium. They can also be produced by optimal control of composition and microstructure, the development of specific substrates for coating and the development of new coatings.     

DESIGN OF A PORTABLE ELECTROTHERMAL VAPORIZATION FLAME ATOMIC EMISSION SPECTROMETRY DEVICE FOR FIELD ANALYSIS

A nontraditional, portable flame atomic emission spectrometry (FAES) device has been constructed using a welding industry metal cutting torch as the flame source with a tungsten coil electrothermal vaporization device for sample introduction. Twenty-microliter sample aliquots were pipetted onto a commercially available tungsten filament, and a home-written Visual Basic program was used to automatically dry and atomize the sample. The sample was then transported into the heart of the air-acetylene flame, where it was excited, and the resulting emission signal was focused onto the entrance of a miniature charge coupled device spectrometer. Figures of merit were determined for five alkaline and alkali earth metals of biological and environmental significance. Limits of detection were, on average, 100 times lower than those for traditional flame emission spectrometers. The capabilities of this portable device make it an ideal tool for biological field analysis, particularly in areas where traditional laboratories are inaccessible.     

Three-dimensional vision-based sensing of GTAW: a review

Automated and robotic welding is now widely used in manufacturing industry. The control of the welding process plays a crucial role in producing quality welds in automated and robotic welding where the assistance from skilled welders is no longer available. In gas tungsten arc welding (GTAW) which is the primary arc welding process for precision joining of metals, the weld pool is the major source of information that can be used to assure the production of desired weld penetration which is the most critical factor determining the weld integrity. To meet this challenge, various sensing technologies have been proposed/studied to sense and obtain the feedback for the weld pool state. This paper summarizes the researches on weld pool state sensing: conventional sensing technologies, vision sensing technology, and multi-sensor information fusion technology, with emphasis on the analysis of three-dimensional vision sensing methods. And three-dimensional vision sensing, multi-sensor technology, intelligent modeling, and effective commercial product development show the future trends of GTAW penetration sensing.     

Chemical Interactions Involved in the Formation of Oxidation-Resistant Solid Lubricant Composites

Solid lubricating compacts of tungsten diselenide-gallium alloys are currently under development for use as self-lubricating members in high speed-high temperature ball bearing systems. The material is of considerable interest due to the fact that it resists oxidation at temperatures three times higher than pure tungsten diselenide. This paper discusses initial studies of the physical and chemical changes that occur in these compacts during a heal-treating cycle required in their fabrication. Speculations regarding the mechanism responsible for their oxidation resistance are presented.     

Smart Crown轧辊轧制钨板过程有限元分析

针对传统轧制工艺轧制钨板过程中,轧辊易损坏、钨板轧废严重等现象,基于有限元分析软件,研究利用smert Crown轧辊轴向移动轧制钨板,根据要求设计了一款Smart Crown轧辊.从辊形、应力、应变以及磨损方面,分析钨板轧制情况,发现同等轧制条件下,Smaut Crown轧辊轴向移动轧制钨板的新工艺优于传统钨板轧制工...     

富勒烯与纳米二硫化钨极压抗磨协同性能研究

为探讨富勒烯与纳米二硫化钨的极压抗磨协同性能,利用四球试验机考察富勒烯与纳米二硫化钨复配后在PAO基础油中的摩擦学性能;采用扫描电子显微镜对试验钢球磨痕形貌进行分析,探究富勒烯与纳米二硫化钨的协同作用机制。结果表明:富勒烯与纳米二硫化钨单剂对PAO基础油减摩抗磨效果的改善不明显,而富勒烯与纳米二硫化钨复配后可明显提高油样的减摩抗磨性能,其中质量分数0.01%富勒烯与0.005%二硫化钨复配后减摩抗磨协同效果最优,这是因为富勒烯能够实现滚动摩擦,而纳米二硫化钨能够沉淀到磨损处,起到修复的作用,两者的协同作用,提高了基础油的抗磨减摩性能;富勒烯与纳米二硫化钨复配并不能提高基础油极压性能,这是因为富勒烯不能与纳米二硫化钨生成新的物质来提高基础油的承载能力。     

空心钨极中心负压电弧基础特性研究

为了提高传统钨极惰性气体保护(Tungsten inert gas,TIG)焊电弧的能量密度和热源边界的能量梯度,保证焊接热输入均衡,规避输入能量分散,提出空心钨极中心负压电弧焊接方法,设计并构建空心钨极中心负压电弧焊接系统,介绍系统的组成及操作方法。利用高速摄像机拍摄空心钨极中心负压电弧的宏观形态,进行定点焊接烧蚀试验,并对阳极表面熔池尺寸和焊接接头的宏观形貌进行分析。试验结果表明,在电弧自身刚性的作用下,空心钨极中心负压电弧能够稳定地建立于空心钨极和阳极工件之间;与传统TIG焊电弧相比,在宏观形态上,空心钨极中心负压电弧的弧柱沿径向收缩,呈现拘束状,空心钨极的尖端呈现白炽状态;在焊接接头的宏观形貌上,空心钨极中心负压电弧对应焊接接头的熔深大,熔宽小,焊缝成形好。