浅谈切割技术在电力铁塔制造业中的应用

在电力铁塔制造业中,如何解决板件的切割下料问题,已成为企业面临的重要课题.结合企业实际,谈谈切割技术在铁塔制造企业中的应用.     

金属板材合理尺寸的选择

通过选择尺寸适宜的金属板材,可以明显提高金属板材的利用率,这里阐述合理选择金属板材尺寸的方法,给出了实例数据的分析与排样结果。     

制造业信息系统应用效益的确认与量化

企业信息系统应用效益的正确评价是保证其投资有效性的重要手段之一。本文讨论制造业信息系统应用的技术经济特点 ,指出应根据输入输出数据流的分析全面确认信息系统应用的效益源 ,并采用适当的方法加以量化。以计算机排样系统为例 ,对采用数据流分析法评价信息系统的方法加以说明。分析结果表明通过数据流分析可有效提高信息系统应用效益估计的准确性     

Micro/nano sculpturing of hardened steel by controlling vibration amplitude in elliptical vibration cutting

A new ultra-precision sculpturing method in micro/nano scale for difficult-to-cut materials is proposed in the present research. Elliptical vibration cutting technology is well-known for its excellent performance in achieving ultra-precision machining of steel materials with single crystal diamond tools. Elliptical vibration locus is generally controlled and held to a constant in practice. On the contrary, the proposed method utilizes the variations of the elliptical vibration locus in a positive manner. Depth of cut can be actively controlled in elliptical vibration cutting by controlling vibration amplitude in the thrust direction. By utilizing this as a fast tool servo function in elliptical vibration cutting, high performance micro/nano sculpturing can be attained without using conventional fast tool servo technology. A high-speed amplitude control system is developed for elliptical vibration, with a bandwidth of more than 300 Hz, where the vibration amplitude can be controlled within 4 μm_p-p. The developed control system is applied to sculpturing ultra-precision nano textured grooves on hardened steel with single crystal diamond tools. It is confirmed that the textured grooves have the desired shapes, and their profiles agree well with the vibration amplitude commands input to the control system. Further, a high performance micro/nano sculpturing system for plane surfaces is developed, where the vibration amplitude is controlled in synchronization with the planing motion of an ultra-precision machine tool. Nano sculpturing experiments on hardened steel, carried out by the developed system, are reported, as well as consequent picture images and a variety of dimple patterns that were formed successfully on the hardened steel as nano-scale sculptures.     

钢板切头矫直机传动方式改进设计

针对钢板切头矫直机原设计传动形式的缺陷,改变原有传动形式,通过对减速箱齿轮的受力分析,计算出原传动所提供的扭矩,将减速电机更换为液压马达。生产实践证明,此改进可降低设备故障率,提高产量。     

钢铁企业用阀门电动装置的特点

叙述了钢铁企业对阀门电动装置的要求，提出了用于钢铁企业阀门电动装置在设计、选型及使用中应注意的问题。     

一种中厚钢板全自动切割设备的环保工艺及装备

介绍氧乙炔焰、等离子弧水下切割中厚钢板工艺及防撞机构的结构特点、工作原理,对解决现场环保问题,有重要的实用意义.     

Study on the protective effect of built-up layer in dry cutting of stainless steel SUS304

This work presents a systematic and comprehensive investigation of the protective effect of built-up layer (BUL) in dry cutting of stainless steel SUS304. A detailed examination of BUL and built-up edge (BUE) formation conditions, their formation mechanisms, and their protective effect was carried out at different cutting speeds (5–140 m/min), and different feed rates (0.02–0.1 mm/rev). The uncoated cemented carbide tool was used as a cutting tool. The dimensions of BUL/BUE and tool wear were measured by scanning electron microscope (SEM) and laser confocal microscopy (LCM). The protective effect of BUL/BUE was characterized using flank wear progression, as well as crater wear progression, cutting force analysis, and surface roughness analysis. As a result, it was found that BUE forms around the cutting edge at low cutting speeds (5–20 m/min), and BUL, which resembles a water drop, forms on the tool rake face at cutting speeds equal to or above 40 m/min. And a thin layer of flank built-up (FBU) can form on the tool flank face as the cutting speed increases from 40 m/min to 140 m/min. The BUL/BUE formation mechanism was also confirmed. It was revealed that BUL can be considered as a protective layer, which can not only prevent the tool rake face from wear but also decrease the tool flank wear, but BUE can only prevent the crater wear; and to a certain extent, the thin layer of FBU can also work as a protecting layer on the worn tool flank face in dry cutting of SUS304. It was also revealed that the height of BUL plays a very important role in its protective effect. Meanwhile, it was found that BUL and the thin layer of FBU have no or few influences on the amplitude variation of cutting forces and on the surface roughness. These results indicated that BUL can be used to realize the self-protective tool (SPT) in cutting of difficult-to-cut material such as SUS034. In addition, the research also proved that it is necessary to take the influences of BUL, BUE, and FBU formations on tool wear into account in the tool wear model in order to achieve high-precision prediction.     

Defining the effects of cutting parameters on burr formation and minimization in ultra-precision grooving of amorphous alloy

Amorphous nickel phosphorus (Ni-P) alloy is a suitable mold material for fabricating micropatterns on optical elements for enhancing their performances. Ultra-precision cutting is preferred to be used to machine the mold material for high precision in a large workpiece. However, burrs and chippings always form and are detrimental especially when fabricating micropatterns. The formation mechanisms of burrs and chippings have not yet been revealed precisely in the cutting processes of amorphous alloys, because their cutting behavior is more complex and less discussed in existing researches than that of crystalline metals. In the present study, the burr formation process of amorphous Ni-P is defined and a three-dimensional cutting model using energy method is proposed to predict and minimize burrs and chippings. Microgrooving experiments were conducted with different undeformed chip geometries using three types of cutting tools to observe burr formation processes. Large burrs and chippings were formed when cutting with a tapered square tool and a tilted triangle tool. These large burrs and chippings were found to be induced by large slippages that are unique to amorphous alloys. It was revealed that burrs and chippings appear when the angle between the chip flow direction and the groove edge is less than a critical value. Energy method was used to predict the chip flow directions and the calculated results agree with the experimental ones, which proved that the energy method is valid for designing an appropriate undeformed chip geometry to reduce burrs and chippings in ultra-precision grooving.