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1.
2001年我国机床工具产品进出口继续保持增长,机床工具产品进口大幅度增长,进口金额33.59亿美元,同比增长22.71%,其中金属加工机床进口24.06亿美元,同比增长27.27%;出口继续增长,机床工具产品出口金额8.29亿美元,同比增长5.56%,其中金属加工机床出口2.9亿美元,同比下降2.98%(详见本刊今年第2期和去年第2期刊出的2001年和2000年我国机床工具进出口贸易统计)。  相似文献   

2.
2004年1~6月份机床工具产品进口37.89亿美元,同比增长43.53%,其中金属加工机床进口26.31亿美元,同比增长42.72%,占机床工具产品进口额69.4%。  相似文献   

3.
《机械工程师》2005,(4):13-13
2004年我国机床工具产品进口89.3亿美元,同比增长45%,其中金属加工机床(金切机床和成形机床)进口59.16亿美元,同比增长4.2%。金属加工机床成为第一大类进口产品,占机床工具总进口额的三分之二。  相似文献   

4.
进入21世纪以来,我国机床市场极为火爆.自2002年起.我国已连续3年保持了世界第一机床消费大围的地位。这期间我国机床进口金额也快速增长.2004年.我国机床工具产品进口金额迅猛增长达到8931亿美元,同比增长4496%.比2003年增幅高出了11个百分点。其中金属加工机床(包括金属切削机床和金属成型机床)的进口金额迭5916亿美元.占机床工具产品进口总额的6624%。从2002年起,  相似文献   

5.
一、上半年我国金属加工机床进口概况 2003年上半年我国金属加工机床进口保持较商增长。金属加工机床进口61593台(包括台钻、砂轮机、抛光机7250台),同比增长10.54%,金额184353.3万美元,同比增长38.6%,其中数控金属加工机床进口13869台,同比增长31.76%,进口金额122630.4万美元,同比增长62.58%。上半年金属加工机床、数控金属加工机床各月累计进口金额同比增幅走势见图1。  相似文献   

6.
2006年机床工具产品进出口贸易继续保持较快增长,进出口贸易总额149.54亿美元,同比增长15.4%,发展势头良好。其中,机床工具产品进口金额111.36亿美元,同比增长11.75%;出口金额38.18亿美元,同比增长27.5%,增幅比上年回落5.4个百分点。机床工具产品中,金属加工机床进口金额72.4亿  相似文献   

7.
受国家宏观调控以及近几年机床工具高额进口基数的因素影响,2005年上半年我国机床工具进口总额为47.9亿美元,同比增幅达到22.3%。其中金属加工机床进口60117台,金额为32.3亿美元,同期比较分别下降4.3%和增长22.8%。2005年上半年金属加工机床贸易逆差为28.9亿美元,比上年同期增加了20.2%。  相似文献   

8.
《数控机床市场》2010,(7):10-10
海关发布的最新统计数据显示,2010年1-5月,中国累计进口金属加工机床40,747台,较去年同期增加54.5%;累计进口金额约为31.28亿美元,同比增长25.8%。2010年5月,中国进口金属加工机床8,874台,环比减少了18.83%,同比则大幅增加165.93%:进口金额约为6.5亿美元,环比下降12.22%,同比则增长48.84%。进口平均单价为73,293美元/台,环比增长8.14%,  相似文献   

9.
国产机床压力大机床工具存在盲目进口 2004年我国机床工具产品进口89.3亿美元,同比增长45%,其中金属加工机床(金切机床和成形机床)进口59.16亿美元,同比增长4.2%。金属加工机床成为第一大类进口产品,占机床工具总进口额的三分之二。2004年,我国机床工具产品出口22.5亿美元,同比增长33.5%,其中金属加工机床出口5.4亿美元,同比增长42.4%。也就是说,机床工具产品去年进口总值是出口的4倍,进出口逆差高达66.8亿美元。分析一下这66.8亿美元的逆差,有其合理的一部分。2004年,我国金属加工机床产值约合40.8亿美元,进口金属加工机床59.16亿美元,出…  相似文献   

10.
2004年,我国机床工具大行业进出口创历史纪录,1~12月机床工具行业进出口总额突破100亿美元大关,达到111.8亿美元。但进出口逆差进一步扩大,2004年1~12月,机床工具产品进出口逆差达到66.8亿美元,同比增长50.8%。进口增幅高于出口增幅11.7个百分点。其中金属加工机床进出口逆差高达53.76亿美元,比2003年同期增加16.25亿美元,同比增长43.3%……  相似文献   

11.
介绍了一种机床主轴锥孔自磨工具,阐述了该工具的结构、工作原理和操作方法,并分析影响主轴锥孔加工精度因素,解决了传统工艺方法难以保证主轴锥孔精度的问题,实践证明该夹具具有较强的实用性.  相似文献   

12.
为了提高数控机床加工的效率和精度,在数控系统软件支持下,增设一个相对独立的自动对刀程序模块来实现简易的自动对刀控制.  相似文献   

13.
一、主轴的高速化近几年来 ,为了提高生产率 ,机床的一个重要的发展是主轴的高速化。 1999年在我国的展览会上就展出了 7台转速在 10 0 0 0r/min以上的机床 ,表明我国在主轴的高速化上有了一个良好的开端 ,在主轴的高速化方面 ,支撑它的外围技术是多方面的 ,如支承系统、润滑系统、结构材料等。以滚珠轴承为例 ,随着保持架材料的变化、形状的最佳化和滚珠的小直径化 ,发展了陶瓷滚珠轴承 ,使滚珠轴承的转速延伸到了高速的领域 ;现在又发展成为气体静压、液体静压、动压以及动静压混合形式的各种主轴 ;由于更高转速的要求 ,磁力轴承形式…  相似文献   

14.
Machining of aluminum and its alloy is very difficult due to the adhesion and diffusion of aluminum, thus the formation of built-up edge (BUE) on the surface. The BUE, which affects the surface integrity and tool life significantly, affects the service and performance of the workpiece. The minimization of BUE was carried out by selection of proper cutting speed, feed, depth of cut, and cutting tool material. This paper presents machining of rolled aluminum at cutting speeds of 336, 426, and 540 m/min, the feeds of 0.045, 0.06, and 0.09 mm/rev, and a constant depth of cut of 0.2 mm in dry condition. Five cutting tools WC SPUN grade, WC SPGN grade, WC + PVD (physical vapor deposition) TiN coating, WC + Ti (C, N) + Al2O3 PVD multilayer coatings, and PCD (polycrystalline diamond) were utilized for the experiments. The surface roughness produced, total flank wear, and cut chip thicknesses were measured. The characterization of the tool was carried out by a scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) pattern. The chip underface was analyzed for the study of chip deformation produced after machining. The results indicated that the PCD tool provides better results in terms of roughness, tool wear, and smoother chip underface. It provides promising results in all aspects.  相似文献   

15.
Non-singular tool path planning by translating tool orientations in C-space   总被引:1,自引:0,他引:1  
This paper discusses the singular problem in five-axis machining of freeform surfaces. At first, the generating mechanism of the singularities is studied on the unit sphere in the P-system. Then a new method is developed to avoid the singularities by translating the tool orientations in the configuration-space (C-space) at the time just after the initial cutter locations have been generated for a cutter contact (CC) trajectory on the surface. The tool orientation vectors of the initial cutter locations are projected onto the C-space, forming the orientation polyline. In the C-space, a taper circle is defined. The singularities are detected by contact checking between the orientation polyline and the taper circle. Once they contact, the orientation polyline is translated by a minimum translating vector to avoid the contact. The minimum translating vector is picked on the offset polyline of the original orientation polyline. After that, the translated orientation polyline is inversed to calculate the optimized cutter locations in the P-system. The benefit of avoiding singularities at the tool path planning stage is that the original CC points on the CC trajectory are respected. The developed method is programed and tested through contrastive experiments. Results show that the optimized cutter locations can effectively avoid the singularities.  相似文献   

16.
Size effect and tool geometry in micromilling of tool steel   总被引:5,自引:0,他引:5  
The market for freeform and high quality microdies and moulds made of steel is predicted to experience a phenomenal growth in line with the demand for microsystems. However, micromachining of hardened steel is a challenge due to unpredictable tool life and likely differences in process mechanism compared to macro-scale machining. This paper presents an investigation of the size effect in micromilling of H13 hardened tool steel. In this case, the size effect in micromilling hardened tool steel was observed by studying the effect of the ratio of undeformed chip thickness to the cutting edge radius on process performance. The paper explores how this ratio drives the specific cutting force, surface finish and burr formation in micro-scale machining. In addition, the effect of different microend mill geometry on product quality was explored. The paper provides a valuable insight into optimum micro-scale machining conditions for obtaining the best surface finish and minimizing burr size.  相似文献   

17.
~~2005年机床工具主要产品进口税率明细表  相似文献   

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