CUTTING TOOLS
Materials-Centered Manufacturing Takes Center Stage “There has been a decided shift to materials-centered manufacturing,” said consultant Bert Erdel, PhD. “Titanium, undeniably, is the material of choice for aircraft structures and engine parts—be it as a single alloy or a stacked material (Ti-Composites) for advanced fan and skin designs or the alternative material for the engine hot zone as an Intermetallic (Ti-Al) or the alternative material for advanced landing gears. Of the many different titanium alloys, 6 Al-4 V is still the most common and its machining characteristics are pretty well known,” said Erdel. Because of its hardness and high heat resistance, every element of the machining process has to be optimized, including cutting tool, cutting tool materials, coolant, machin- ing data, machine and machine spindle, toolpath, toolhold- ing, and part fi xturing. “It is the holistic approach that yields Best Process,” said Erdel. “Because titanium is expensive, it’s what you do in the machining process that really counts. Double your feed rate, for example, and you can get more
Erdel said development of new tools can make a big
difference. He cites the robust machining of titanium with a Z Carb HPR solid-carbide end mill with M coating from SGS Tool Co. (Munroe Falls, OH) as an example. “The Z Carb HPR gives 40–45% better tool life than any other tool in the market by virtue of its patent pending, innovative design and coating. This true high-performance tool dramatically reduces the radial load on the machine spindle, shields the tool from premature failure due to temperature build-up and secures a smooth chip fl ow away from the cutting area dur- ing machining. Featuring special fi ve-fl ute design, variable indexing geometry and the Ti-Namite M-coating plus coolant exit from the middle of the tool, the Z Carb HPR-series allow for extreme high metal removal rates and excellent surface fi nishes,” said Erdel.
Hard metal machining systems from Mitsui Seiki include the latest tool/ spindle interfaces and can handle up to 35,000 inch-pounds of tool taper moment loads to accommodate long tools cutting highly resilient materials like titanium and Inconel.
parts out the door and thus can compensate for the higher acquisition cost of the material itself,” said Erdel who points to the fact that Boeing owns the material and under its Revert program reclaims and recycles titanium chips from its suppliers so as to assure a ready (secondary) supply stream.
48
AdvancedManufacturing.org | January 2016
Big Target to Shoot For: Twice the Production in Same Space According to Scott Walker, president, Mitsui Seiki USA (Franklin Lakes, NJ), Boeing has set a goal of doubling pro- duction in the same amount of fl oorspace, whether in assembly operations, or machining titanium. Translated into machining titanium terms that means that what they would like to see is a ma- chine tool capable of getting 2000 ft-lb (2711 N•m) of torque at 500 rpm compared with today’s 2000 ft-lb at 100 rpm on a geared spindle machine. “That machine in a horizontal trunnion platform that best suits FMS strategies doesn’t exist at this time, but I think that what’s going to happen is that machine tools are going to evolve with totally new designs to provide torque within the 300–500 rpm range at high-torque values like 2000 ft-lb or more,” said Walker. “Cutting edges are getting better, but new tools will have to be developed. Coolant volumes that are running as high as 50 gpm [189 L/ min] through the spindle at 1500 psi [10 MPa] will be improved. New machine designs must consider the volume of chips that have to be evacuated as they will be increased by a factor of two or three.” Mitsui Seiki’s current designs popular in the aero- space industry are its HU 100 series four and fi ve- axis horizontal machining centers with three-speed gear box that develop 2000 ft-lb at 100 rpm. “Market demand for our products is in the 630-mm to 2.5-m sizes for structural compo- nents and jet engine parts,” said Walker. “In titanium blade ma- chining what they are looking for is to be able to run at 90 ipm
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116