Хонинговальные головки

The application illustrated in Figure 12.1 is the internal grinding of large aeroengine shroud assemblies for aircraft engines. Traditionally, the part was ground using seeded gel (SG) abrasive, but the SG process was replaced by a vitrified CBN wheel that reduced grind cycle time by 50%. The greatest time saving was achieved by the elimination […]

The enhanced strength and toughness of ZTA ceramics have made these materials more widely applicable and more productive than plain ceramics and cermets for machining steels and cast irons. ZTA ceramics can be used as cutting tool inserts for metal cutting applications [Sornakumar and Gopalakrishnan 1995]. Cutting inserts are made by sintering followed by grinding […]

Generating the necessary tolerance on any slideway system can be expensive and time consuming. The ways are either cast into the base and ground and/or are scraped, or the base is ground and ways bought “off-the-shelf” are bolted on. Grinding a base requires a significant investment in capital equipment for a slideway grinder while scraping […]

Grinders for high efficiency deep grinding (HEDG) and superabrasive high-speed grinding with plated wheels have been influenced strongly by machining center design. In many cases, the grinders are, in fact, a multipurpose machining/grinding/drilling center. The wheels are designed around sizes of 125 mm up to 300 mm running at up to 120 m/s. Numerous machine […]

Alongside infeed (i. e., depth of cut), the feedrate considerably affects the total machining time in reciprocating grinding. Increasing the feedrate results in higher average chip thickness and length, and thus in an increase of grinding forces and thermal stress. A repeated start of the grinding wheel to the workpiece and the punctual impact stresses […]

The various new and competing technologies, each requiring somewhat different process conditions, require careful consideration of the end users’ true needs especially when considering capital equipment expenditures. This can be readily understood by considering as an example the recent changes in the processing of nickel alloy-based aeroengine components, for example, high tem­perature blades and vanes. […]

The final method of grinding is a combination of infeed with traverse. This is a typical operation for long shafts and cylinders. An extreme form is roll grinding for the paper and steel industries. The nature of the wheel wear and the actual Q’ values become less well defined as the wheel is cutting on […]

The incoming part quality is critical. The grind process is often used to “fix” problems earlier in the line and blamed for their deficiencies. The part must come in burr free from any premachining/ heat treat process and free of any contamination such as tumbling media used for deburring. (Grit blast media or loose burrs […]

In through-feed grinding, the grinding wheel is set at a fixed distance from the control wheel as in Figure 19.9. Through-feed is employed for longer workpieces and also for a continuous stream of short workpieces. In most cases, the length-to-diameter ratio of the workpieces is greater than one. The workpiece is fed between guide plates […]

19.10.1 Introduction Under particular through-feed centerless grinding conditions, results presented by Koenig and Henn [1982] showed that the minimum cost per part was achieved at removal rates between 1 and 6 mm3/mm/s. Increasing or reducing removal rate from this range increased costs. Such results are useful for demonstrating an approach to optimization. In this section, […]