Parts for ToolsTechnicalReference User’s Guide - Technical Reference Drilling To o l s Nomenclature for solid carbide drills Shank Lead Point angle Helix angle Flute length Shank length Overall length Thinning edge Thinning Web thickness Secondary relief Cutting edge Thinning Primary relief Margin Secondary relief Oil hole Chisel Primary relief Heel Body clearance Chisel edge Cutting forces and power requirement ᭹Twist drill ᭹Material constant compensating for power requirement and thrust force Power requirement Tensile strength Brinell Material Pc=KD2n ( 0.647 + 17.29f )×10-6 Workpiece material MPa(N/mm2) {Kgf/mm2} hardness(HB)constant(K) (kW) Cast iron 210 21 177 1.00 Thrust force Cast iron 280 28 198 1.39 Cast ironTc=570KDf 0.85 350 35 224 1.88 (N) Aluminium 250 25 100 1.01 Low carbon steel (JIS S20C) 550 55 160 2.22 Torque Free cutting steel (JIS SUM32) 620 62 183 1.42 Mc= KD2 ( 0.630 + 16.84f ) Manganese steel (JIS SMn438) 630 63 197 1.45 (N·m) 100 Nickel chromium steel (JIS SNC236) 690 69 174 2.02 4115 steel Cr0.5, Mo0.11, Mn0.8 630 63 167 1.62 Pc : Power requirement (kW) Chromium molybdenum steel (JIS SCM430) 770 77 229 2.10 Tc : Thrust force (N) Chromium molybdenum steel (JIS SCM440) 940 94 269 2.41 Mc : Torque (N·m) Nickel chromium molybdenum steel (JIS SNCM420) 750 75 212 2.12 D : Drill diameter (mm)〔DC〕 Nickel chromium molybdenum steel (JIS SNCM625) 1,400 140 390 3.44 f : Feed (mm/rev) Chromium vanadium steel n : No. of revolutions (min-1) Cr0.6, Mn0.6, V0.12 580 58 174 2.08 K : Material constant.... Refer to the Table at right Cr0.8, Mn0.8, V0.1 800 80 255 2.22 〔 〕The notation in the brackets is the one used in the catalog (ISO compliant) L068 www.tungaloy.com