点评现阶段机床砂带磨削的加工特点.doc

点评现阶段机床砂带磨削的加工特点

　　二、砂带磨削原理

Second, the abrasive belt grinding principle

　1.主轴传动装置。有单速或具有较大灵活性的变速传动,有时装有可逆电动机,以改变砂带的运动方向。皮带速度为10～50m/min,通常取16～30m/min,主传动装置的功率,在每10mm宽的砂带上是0.3～0.7kw。

1. Main shaft driving device. Has a single speed or variable speed drive with larger flexibility, sometimes with reversible motor, in order to change the movement direction of the abrasive belt. The belt speed is 10 ~ 50 m/min, usually take 16 ~ 30 m/min, main transmission power, sand belt in every 10 mm wide is 0.3 ~ 0.7 kw.

　　2.砂带张紧装置。保持磨削及导向时砂带的适当张力在砂带磨削过程中起到重要作用,它影响到砂带的切削性能和加工零件表面粗糙度。当增加砂带拉力时,可提高金属切除量,但同时也提高表面粗糙度值和磨料覆盖层的消耗量。

2. The belt tensioning device. Keep grinding and guide the appropriate tension in the belt grinding of abrasive belt play an important role in the process, which affect the cutting performance of the abrasive belt surface roughness and machining parts. When increase the abrasive belt tension, metal removal can be improved, but also improve the surface roughness value and consumption of abrasive layer.

　　3.砂带导向装置。砂带工作时,惰轮或张紧轮应当可以调整,使砂带定位及对中,根据砂带的宽度,这一装置可以手动或自动。砂带宽度大于200mm时,通常使用自动导向装置,使接触轮与张紧轮之间的砂带自动对正。

3. The abrasive belt guide. Abrasive belt, idler or tensioning wheel should be able to adjust, make and the positioning of the abrasive belt, according to the width of abrasive belt, this device can be manual or automatic. Abrasive belt width is larger than 200 mm, we usually use automatic guiding device, the contact between the wheel and tension wheel abrasive belt for automatically.

　　4.接触轮。接触轮在磨削点上支承砂带,其本体是用铝或钢制成,轮上覆盖橡胶、纤维、毛毡或其它材料制造的弹性圈(厚度为3～15mm)。根据需要,可制成各种密度橡胶轮,轮的表面制成交错开槽式或平滑式。使用各种橡胶化合物作为接触轮的覆盖面,以满足一定的磨削要求。

4. Contact wheel. Contact at that point in grinding wheel bearing sand belt, its ontology is made of aluminum or steel wheel cover rubber, fiber, felt, or other materials to make the elastic ring for 3 ~ 15 mm (thickness). According to the need, can be made into all kinds of rubber wheel density, the surface of the wheel made staggered slot type or smooth. Using a variety of rubber compounds as the contact wheel coverage, to meet a certain requirement for grinding.

　　5.若在砂带后面安装一块型板(钢、硬质合金或铸铁平板)来代替接触轮,则可完成磨边、四边形、端面、平面及精磨工作,保证零件的平面度或直线性。

5. If the abrasive belt installed behind a piece of plate (steel, hard alloy or cast iron plate) to replace the contact wheel, can complete the edge grinding, quadrilateral, end face, the planar and fine grinding work, ensure that components of the flatness and linearity.

　　此外还有吸尘系统等。

In addition to dust collection system, etc.

　　三、砂带磨削特点

Three, the abrasive belt grinding characteristics

　　1.加工效率高。经过精选的针状砂粒采用先进的“静电植砂法”,使砂粒均匀直立于基底、且锋口向上、定向整齐排列,等高性好,羟丙基甲基纤维素容屑间隙大,接触面小,具有较好的切削性能。应用这一多刀多刃的切削工具进行磨削加工,对钢材的切除率已达每mm宽砂带200～600mm3/min。

1. The processing efficiency is high. After selection of acicular sand adopts advanced "electrostatic sand method", make the sand even upright in the basement, and edge up, directional lined up, such as sex, let big chip clearance, contact surface is small, has good cutting performance. Used a knife blade of cutting tools for grinding, removal rate of steel per mm wide abrasive belt has amounted to 200 ~ 600 mm3 / min.

　　2.加工表面质量高。砂带磨削时接触面小摩擦发热少,且磨粒散热时间间隔长,可以有效地减少工件变形及烧伤,故加工精度高,尺寸精度可达±0.002mm;平面度可达0.001mm。另外,砂带在磨削时是柔性接触,具有较好地磨削、研磨和抛光等多重作用,矿用风机再加上磨削系统振动小,磨削速度稳定使得表面加工质量粗糙度值小,残余应力状态好,工件的粗糙度可达ra0.4～0.1μm,且表面有均匀的粗糙度。但由于砂带不能修整,故砂带磨削加工精度比砂轮磨削略低。

2. The processing surface quality is high. Abrasive belt grinding contact area small friction produce less heat, heat dissipation and grits time interval is long, can effectively reduce the workpiece deformation and burns, so the machining precision is high, the size precision can be up to + / - 0.002 mm; Flatness can be up to 0.001 mm. In addition, the abrasive belt in grinding is the flexible contact, has a better grinding, lapping and polishing etc multiple effect, plus small vibration grinding system, grinding speed stability makes the surface machining quality roughness value is small, the residual stress state is good, the roughness of the workpiece can reach ra0.4 ~ 0.1 microns, and the roughness of the surface is uniform. But due to the abrasive belt can't repair, so the abrasive belt grinding machining accuracy is lower than grinding wheel grinding slightly.

　　3.工艺灵活性大,适应性强。砂带磨削可以方便地用于平面、外圆、内圆磨削、复杂的异形面加工、切削余量20mm以下的粗加工磨削、去毛刺和为镀层零件的预加工、抛光表面、消除板坯表面缺陷、刃磨和研磨切削工具、消除焊接处的凸瘤、代替钳工作业的手工劳动。除了有各种通用、专用设备外,设计一个砂带磨头能方便地装于车床、刨床和铣床等常规现成设备上,不仅能使这些机床功能大为扩展,而且能解决一些水性油墨难加工零件如超长、超大型轴类、平面零件、不规则表面等的精密加工。

3. Process flexibility, strong adaptability. Abrasive belt grinding can be easily used in plane grinding, cylindrical, inner circle, complex shaped surface processing, the cutting allowance is 20 mm below the rough grinding, deburring and rehearsals for the plating parts, polishing surface, eliminate the slab surface defects, cutting tools, grinding and grinding to eliminate welding of convex tumor, instead of the fitter operation manual labor. Besides there are various kinds of universal and special equipment, design a abrasive belt grinding head can be easily installed in conventional off-the-shelf equipment such as lathe, planer, milling machine, not only can make the machine function is expanded, and can solve some difficult machining parts such as super long, super large axial, flat and irregular surface parts such as precision machining.

　　4.砂带有很大的弹性,因而整个系统有较高的抗振性。

4. The sand with a great deal of resiliency, and thus the whole system has a higher vibration resistance.

　　5.砂带尺寸可很大,适用于大面积高效率加工,且设备简单,操作安全,使用维护方便,更换砂带和培训机床操作人员花费时间较少。

5. Abrasive belt size is very big, suitable for large area processing with high efficiency, and simple equipment, safe in operation and convenient in operation and maintenance, replacement of sand belt and training machine operators spend less time.

　　6.在加工过程中砂带增长,外形和尺寸达不到高精度,加工零件上的尖锐突出部位和用细粒度磨料精磨困难,砂带的坚固性比较低,同时在大多数情况下砂带不可能修正,所以使用期限短。

6. In the growth process, medium sand belt, the shape and size can not meet the high precision, sharp on the outstanding parts and machining parts with fine grit abrasive finishing grinding hard, abrasive belt of robustness is lower, at the same time, in most cases, abrasive belt can't be revised, so life is short.