车削螺旋端面的夹具

我厂为了保证转盘(图1)生产的质量,设计了在普通车床上使用的夹具,用以加工φ84～φ86mm之间螺旋线形端面。夹具由两部分组成,运动部分装在主轴与尾架两顶尖之间,靠模部分由角铁支座1(图2)与靠模轴套5组成。与装中心架方法相同,将角铁支座1固定在车床导轨上适当位置,轴承3装在靠模轴套5的螺旋线形槽内。靠模轴套5孔内两端有花键     

车削大滚子端面和倒角的夹具

在大滚子加工过程中,需要有车端面和倒两端Ｒ角工序,为此我们设计了一种能够加工圆柱滚子、圆锥滚子和球面滚子的夹具（见图１）。夹具的工作原理是：拉杆拉动夹爪座,夹爪座带动夹爪向后移动并收缩,由夹爪上固定的夹块夹紧工件,加工完毕后拉杆前移,夹爪在拉簧的作用下张开,退出工件。图１　　此夹具的特点是：（１）使用寿命长　夹爪采用分体结构,避免了整体夹具的断爪现象;夹爪硬度较高（５８～６２ＨＲＣ）,耐磨性较好;夹具体镶有锥环,锥面磨损后可以更换,夹具体不会磨损。（２）加工范围广　夹爪的涨缩量较大（可达３～６ｍ…     

气门摇臂油槽车削靠模夹具

1 问题的引出如图 1所示零件 ,为发动机气门摇臂 ,主体为铸件内孔压入材料QSn4 4 2 5铜套 ,硬度 1 70～1 80HB。切削性能良好。铜套内孔表面上有一条宽3mm ,深 (0 3± 0 1 )mm的封闭环形油槽需要加工 ,主要控制油槽的轴向位置 9mm、 1 9mm。由于加工批量大 ,因此 ,选择在车床上加工 ,采用靠模夹具 ,结构简单 ,操作方便 ,经实际使用的效果良好。图　 12 夹具结构及工作原理(1 )夹具结构　如图 2所示 ,定位轴 1采用平键 3与靠模 2联接 ,定位套 8用螺钉 7紧固在靠模2上。工件以内孔和端面定位于定位套 8上。开口压板 5采用开口形式 ,便于…     

车削端曲面夹具

在机械加工中,我们常遇到在轴类或盘状零件的端面加工曲面或凹槽等。如铣床起动圈上 V形凹面的加工等 (如图 1所示 )。通常采用在铣床上设计专用夹具进行铣削。但在实际加工中,由于专用铣夹具一般不能实现自动进给,加上铣削刀具的限制,被加工零件的精度很难满足要求,且生产率较低。 　　为此,我们在车床上设计了一种专用夹具,用车削方法加工图 1所示零件的端面凹槽,取得了良好的效果,现介绍如下。 [1] 夹具结构 　　如图 2,夹具体与机床主轴为刚性连接,随机床主轴作旋转运动。装在夹具体上的键将该旋转运动传给过渡套,使与过渡…     

铸铁管法兰端面车削夹具

图1所示铸铁管固接后要求保证直线度,两端法兰孔要求在同一直线上。而当无专用设备时,加工较困难。为此,我们设计了图2所示夹具。 在支撑轴5圆周上加工两组120°均布的M18螺纹孔,支撑轴5的两端中心孔(?)经研磨,顶紧两端     

精车端面夹具的简易设计

在加工零件的端面时,如果零件端面对内孔有较高的垂直度要求,一般应在一次装夹下将零件的端面与内孔同时加工出来,以保证端面的位置要求。但在实际生产中,往往为了提高生产率或因为其他原因,端面与内孔是在分别安装下加工的。例如在第一次安装时加工好内孔,然后在第二次安装时以内孔定位加工端面。由于存在二次安装误差,要保证端面对内孔的垂直度要求,就有一定的困难。为此,对精车端面     

车削端面轴向曲线环槽靠模夹具

介绍在普通车床上车削端面轴向曲线环槽靠模夹具的工作原理。并从理论上系统推导靠模坐标的尺寸及其实际的应用。     

车削长管件端面夹具

托辊是皮带输送机的主要部件。我公司年生产量很大。托辊中主要构件长管如图1所示。原工艺方法先在毛坯外圆上车架口,再用中心架支承车削端面和内孔。这种方法效率低,加工出的工件同轴度差,托辊使用寿命短。为此,我们设计了车削专用夹具如图2。     

精车端面夹具设计探讨

在机械加工工件的端面时,如果工件端面对内孔有较高的垂直度要求,一般应在一次装夹中将工件的端面与内孔同时加工出来,以保证端面的位置精度。但在实际生产中,往往为了提高生产效率或因为其他原因,端面与内孔是在分别两次装夹下加工的,如在第一次装夹时加工好孔,然后在第二次装夹时以已加     

车削端面上深曲线环槽

端面上深曲线环槽的加工工艺比较特殊,除采用曲线靠模外,还必须设计专用的深槽车刀(材料W18Cr4V2,硬度62HRC),车削端面上深曲线环槽的工艺过程比一般的端面槽加工难度要大得多。 1.车刀的设计特点和安装使用 就我们介绍的零件而言:材料为黄铜锻件59—1,环槽直径为φ93.5mm_0~( 0.15),槽宽为3.5_0~( 0.15)mm,槽深为24.5_0~( 0.20)mrn,表面粗糙度值为R_a1.6μm。专用深槽车刀(见图1)的主要几何角度为前角γ=12°～15°,后角α=18°～25°。车刀分为粗加工和精加工两把,精加     

Influence of cutting conditions of cast-metal cutting tools on their wear and durability: Analysis of cutting conditions of tools

The conditions of operation of metal-cutting tools in various applications and of various standard dimensions are analyzed. Long-standing statistical observations at a number of industrial facilities have revealed the dominating mechanisms of wear and the main causes of failure of the tools have been established in response to the conditions of their operation and design features. A range of tools has been selected for comparative durability tests in industrial conditions.     

数控折弯机刀具的优化设计

介绍新型折弯机的分段刀具.重点对分段刀具的设计和技术参数进行分析和阐述,经生产验证,分段刀具结构合理,易拆装,操作方便,运行可靠,可达到实际生产的需要.     

基于仿生学的切削工具研究

现代仿生学研究表明,许多动物经过长期的进化,其牙齿、爪趾和体表等部位逐步形成了优化的几何形状和优良的生物力学功能,使其在切削过程中能够获得最低的切削阻力及较高的使用寿命,这为切削工具的几何参数及力学性能的优化提供了仿生研究的基础。笔者综合介绍了基于动物牙齿、爪趾和体表的切削工具仿生研究现状,并在此基础上对该领域研究的发展趋势进行了展望。     

数控机床刀具和刀具材料的发展动向

主要介绍数控机床刀具的简要分类、数控刀具材料的现状和发展趋势。     

Wear maps for some uncoated cutting tools

The method of using maps and diagrams to present wear rates and wear mechanisms, as well as showing the relationships between them, has been applied to cutting tools. In this summary paper, wear maps obtained earlier for uncoated high-speed steel (HSS) cutting tools are presented together with maps for uncoated carbide cutting tools. Within the two-dimensional area of a wear map defined by two easily controlled machining parameters, namely feed rate and cutting speed, the rates of tool wear, and the wear mechanisms observed during actual dry turning operations, are displayed. The presence of safety zones and least-wear regimes in these maps suggests that it may be possible to optimise actual machining operations so that compromises between rates of material removal, for an acceptable level of productivity, and tool costs can be reached. The concept of using machining-regions maps for practical tool-wear minimisation during machining is also discussed.     

新型陶瓷刀具材料及其发展前景

陶瓷刀具具有优良的切削性能。新型陶瓷刀具已在我国冶金、水泵、矿山机械、轴承、滚珠丝杠、汽车、军工等十几个行业得到应用。针对陶瓷刀具的种类、性能和应用进行了论述．并指出陶瓷刀具材料的发展方向。     

Wear behaviour of alumina based ceramic cutting tools on machining steels

The advanced ceramic cutting tools have very good wear resistance, high refractoriness, good mechanical strength and hot hardness. Alumina based ceramic cutting tools have very high abrasion resistance and hot hardness. Chemically they are more stable than high-speed steels and carbides, thus having less tendency to adhere to metals during machining and less tendency to form built-up edge. This results in good surface finish and dimensional accuracy in machining steels. In this paper wear behaviour of alumina based ceramic cutting tools is investigated. The machining tests were conducted using SiC whisker reinforced alumina ceramic cutting tool and Ti[C,N] mixed alumina ceramic cutting tool on martensitic stainless steel-grade 410 and EN 24 steel work pieces. Flank wear in Ti[C,N] mixed alumina ceramic cutting tool is lower than that of the SiC whisker reinforced alumina cutting tool. SiC whisker reinforced alumina cutting tool exhibits poor crater wear resistance while machining. Notch wear in SiC whisker reinforced alumina cutting tool is lower than that of the Ti[C,N] mixed alumina ceramic cutting tool. The flank wear, crater wear and notch wear are higher on machining martensitic stainless steel than on machining hardened steel. In summary Ti[C,N] mixed alumina cutting tool performs better than SiC whisker reinforced alumina cutting tool on machining martensitic stainless steel.     

PCBN刀具铣削灰铸铁时铣削用量优化的研究

采用单因素分数优选法进行PCBN刀具铣削灰铸铁的耐用度试验,根据最大刀具耐用度的原则给出了最佳铣削速度.应用正交试验法,研究PCBN刀具的铣削用量对刀具耐用度的影响,建立了PCBN刀具耐用度和铣削用量的经验公式,根据试验结果,给出了PCBN刀具铣削灰铸铁的合理铣削用量范围.     

Performance of ceramic tools in high-speed cutting iron-based superalloys

A series of turning tests were conducted to investigate the cutting performance of ceramic tools in high-speed turning iron-based superalloys GH2132 (A286). Three kinds of ceramic tools, KY1540, CC650, and CC670 were used and their materials are Sialon, Al₂O₃–Ti(C,N), and Al₂O₃–SiC_w, respectively. The cutting forces, cutting temperatures, tool wear morphologies, and tool failure mechanisms are discussed. The experimental results show that with the increase in cutting speed, the resultant cutting forces with KY1540 and CC670 tools show a tendency to increase first and then decrease while those for CC650 increase gradually. The cutting temperature increases monotonically with the increase in cutting speed. The optimum cutting speeds for KY1540 and CC650 when turning GH2132 are less than 100 m/min, while those for CC670 are between 100 and 200 m/min. Flank wear is the main reason that leads to tool failure of KY1540 and CC670 while notch wear is the main factor that leads to tool failure of CC650. Tool failure mechanisms of ceramic tools when machining GH2132 include adhesion, chipping, abrasion, and notching. Better surface roughness can be got using CC670 ceramic tools.     

数控车床的坐标系和常用对刀方法的比较

数控车床在操作过程中,首先遇到的问题就是如何对刀,对刀的精度高低直接影响工件的加工精度。并对数控车床的坐标系和常用的对刀方法进行详细的介绍。