西北工业大学机电学院
English Translation Material
1. Transfer Machine
The highest degree of automation with special-purpo, multifunction machines is achieved by using柑橘花 transfer machines. Transfer machine are esntially a combination of individual workstations arranged in the required quence, connected by work transfer devices, and integrated with interlocked controls. Workplaces are automatically 七夕送什么 transferred between the stations, which are equipped with horizontal, vertical, or angular units to perform machining , gaging ,workplace repositioning, asmbling, washing, or other operation. The two major class of transfer machines are rotary and in-line types.
An心情焦虑怎么缓解 important advantage of transfer machines is that they permit the maximum number of operations to be performed simultaneously. There is relatively no limitation on the number of workplace surface or planes that can be machined, since devices can be interpo
d in transfer machines at practically any point for inverting, rotating, or orienting the workplace, so as to complete the machining operations. Work repositioning also minimizes the need for angular machining heads and allows operations to be performed in optimum time. Complete processing from rough casting or forging to finished parts is often possible.
One or more finished parts are produced on a transfer machine with each index of the transfer system that moves the parts from stations to stations. Production efficiencies of such machines generally range from 50% for a machine variety of different旧手机怎么处理 parts to 85% for a machine producing one part, in high production, depending upon the workplace and how the machine is operated(material handling 33ehmethod, maintenance procedures, etc. )
All types of machining operations, such as drilling, tapping, reaming, boring, and milling, are economically combined on transfer machines. Lathe-type operations such as turning and facing are also being performed on in-line transfer machine, with the workplace being rotated in lected
machining stations. Turning operations are performed in lathe-type gments in which toolholders are fed on slides mounted on tunnel-type bridge units. Workplace are located on centers and rotated by chucks at each turning station. Turning stations with CNC are available for u on in-line transfer machine. The CNC units allow the machine cycles to be easily altered to accommodate changes in workplace design and can also be ud for automatic tool adjustments.
Maximum production economy on transfer lines is often achieved by asmbling
西北工业大学机电学院
parts to the workplaces during their movement through the machine. such items as bushings, als, welch plugs, and heat tubes can be asmbled and then machine or tested during the transfer machining quence. Automatic nut torquing following the application of part subasmblies can also be carried out.
Gundrilling or reaming on transfer machines is an ideal application provided that proper machining units are employed and good bushing practices are followed. Contour boring and turning of spherical ats and other surface can be done with tracer-controlled single-point inrts, thus eliminating the need for costly special form tools. In-process gaging of reamed or bored holes and automatic tool tting are done on transfer machines to maintain clo tolerances.
Less conventional operations sometimes performed终于开学了 on transfer machines include难受 grinding, induction heating of ring gears for shrink-fit pressing on flywheels, induction积极关注 hardening of valve ats, deep rolling to apply compressive preloads, and burnishing.
Transfer machines have long been ud in the automotive industry for production rates with a minimum of manual part handling. In addition to decreasing labor requirements, such machines ensure consistently uniform, high-quality parts at lower cost. They are no longer confined just to rough machining and now often eliminate the need for subquent operations such as grinding and honing.
More recently, there has been an increasing demand for transfer machines to handle lower volumes of similar or even different parts in smaller sizes, with means for quick changeover between production runs. Built-in flexibility, the ability to rearrange and interchange machine units, and the provision of idle stations increas the cost of any transfer machine, but such feature are economically feasible when product redesigns are common. Many such machines are now being ud in nonautomotive applications for lower production requirements.
