Question

ceramic ball and roller bearings are used when high temperature, marginally lubricated conditions occur. The bearings can be made lubrica high speed, or ,mics or just the ball and rollers, in which case they are referred trom c to as hybrid bearings include aureybrid bearings (Fig. 11.25). Examples of machines utilizing ceramic and ubid bearings include high-performance machine-tool spindles (see Section 8.13), l-can seaming heads, high-speed flow meters, and the Space Shuttle main hooster rocket's liquid oxygen and hydrogen pump sy of Timken, Inc. Inding removes either U hickel, a process referred to as pla .1U). The need for planarization is obvious when it is nsional MEMS devices require micrometer tolerances on icrometers thick. Planarization is difficult to achieve, Section 9.7) leads to preferential removal of the soft l hundreds of th smearing of the ing pro meta s procedure, referred to as nanogr etal. Planarization is usually accomplished w Plan th a rinding. Here, a diamond slurry to maintain flatness lapplate is used to remove mat 75-mm diameter substrate. d 1um over a ction 10.2.1), the PMMA resist is then exposed to synchro rdiation and removed by exposure to an oxygen plasma or through sol The result is a metal structure, which may be used for further of freestanding metal structures produced through electrode ra t extraction. of nickel are shown in Fig. 13.45. 100 pm n and (bì detail of nickel lines and A 250 mm-wide annealed brass 70-30 strip is rolled from a thickness of 20 mm to 12mm. For a roll radius of 300 mm and roll rpm of 100, estimate the total power required for this operation. hu Ea (6 43) as (See also Table 1.1) Date Development 1500-1600 1600-1700 1700-1800 Water power for metalworking: rolling mills for coinage strips. Hand lathe for wood; mechanical calculator Boring, turning, and screw cutting lathe, drill press. 1800-1900 Copying lathe, turret lathe, universal milling machine; advanced mechanical calculators 1808 1863 Sheet-metal cards with punched holes for automatic control of weaving patterns in looms Automatic piano player (Pianola) 1900-1920 Geared lathe; automatic screw machine; automatic bottle-making machine. 1920 1920-1940 1940 1943 1945 1947 1952 1954 1957 1959 1960 1965 1968 1970s First use of the word "robot." Transfer machines; mass production First electronic computing machine. First digital electronic computer. First use of the word "automation." Invention of the transistor. First prototype numerical control machine tool. Development of the symbolic language APT ( Commercially available NC machine tools. Integrated circuits; Industrial robots. Large-scale integrated circuits. Programmable logic controllers First integrated manufacturing system; spot welding of automobile bodies with robots; microprocessors Automatically Programmed Tools); adaptive control first use of the term "group technology." minicomputer-controlled robot; flexible manufacturing system; group technology Artificial intelligence; intelligent robots; smart sensors; untended manufacturing cells. 1990-2000s Integrated manufacturing systems; intelligent and sensor-based machines; telecommunications and global 1980s manufacturing networks; fuzzy-logic devices; artificial neural networks; Internet tools; virtual environments; high-speed information systems. Conventional job shop Flexible manufacturing system Rapid prototyping facility Manufacturing cell Flexible manufacturing line Stand-alone NC production Conventional flowline Soft automation + Hard automation Increasing productivity

Answer 1

1。44 2 16 mm 47M Total Cfever tion Powes nercired for the 0O 60, 00 O BIlIKW