Каталог Stellram токарный инструмент - страница 201

Заказ инструмента: http://steelcam.org Turning Technical 8 (343) 382-52-03 | sales@sverla-ekb.ru Radius Value / Surface Finish Radius Value / Surface Finish Formula Turning Inserts The radius of the insert has a significant role to play The formula to calculate the feed rate: in the quality of the surface finish, which is directly in relation to the feed rate (fn). With a larger radius, better Ra x rε surface finishes can be maintained at higher feeds. The f = use of a larger radius gives a larger surface contact area and causes an increase in power and cutting force. 50 For roughing operations, it is preferable to choose a large f2 radius to ensure corner strength of the insert. However, Rmax = for some materials it is preferable to use a smaller radius 8 x rε to maintain a softer cut. The insert is more fragile but can qualify for operations that are sensitive to vibration. The mean value Ra, can be calculated with following formula: Generally an insert is used with a maximum feed equal to half its radius. The minimum feed is related to edge 2 preparation or to the start of its chip control. An increase f x 50 in cutting speed can also contribute to surface quality. Ra = rε Average value of feed for each radius Rmax = profile depth Radius (mm) 0,4 0,8 1,2 1,6 2,4 rε = nose radius f (mm/turn) 0,12-0,25 0,25-0,5 0,36-0,7 0,5-1 0,7-1,6 fn = feed In finishing operations the insert radius and the feed effect the superficial roughness and the dimensional accuracy. Surface finishing Radius of insert Ra Rt 0,4 0,8 1,2 1,6 2,4 µm µm f mm/r 0,60 2 0,07 0,10 0,12 0,14 0,17 1,60 4 0,11 0,15 0,19 0,22 0,26 3,20 10 0,17 0,24 0,29 0,34 0,42 6,30 16 0,22 0,30 0,37 0,43 0,53 8,00 25 0,27 0,38 0,47 0,54 0,66 Summary: Value of Ra & Rt based on the radius Surface finishing Diameter of round inserts value and feed. Ra Rt 10 12 16 20 25 µm µm f mm/r 0,60 2 0,25 0,28 0,32 0,36 0,40 1,60 4 0,40 0,44 0,51 0,57 0,63 3,20 10 0,63 0,69 0,80 0,89 1,00 6,30 16 0,80 0,83 1,01 1,13 1,26 8,00 25 1,00 1,10 1,26 1,42 1,51 C200 www.kennametal.com