Wholesale Jobber Length Drills Series

Just different length from DIN standard.

DIN 338ASME B.94-11MDIAMETER          FLUTE OVERALL Oal.SIZE  Dec.DIAFLUTE Dec.FLOVERALL Dec.OALh8(mm)LENGTHLENGTHDifferenceInEquiv.mmLENGTHEquiv.mmLENGTHEquiv.mm1.00 12343.39%1/320.0312 0.79 1/20.5000 12.93 1-3/81.3750 35.15 1.50 184020.21%1/160.0625 1.59 7/80.8750 22.68 1-7/81.8750 48.08 2.00 24494.84%5/640.0781 1.98 11.0000 25.97 22.0000 51.37 2.50 30571.47%3/320.0938 2.38 1-1/41.2500 32.44 2-1/42.2500 57.84 3.00 336110.62%7/640.1094 2.78 1-1/21.5000 38.90 2-5/82.6250 67.48 3.20 36658.87%1/80.1250 3.18 1-5/81.6250 42.19 2-3/42.7500 70.77 3.50 39705.80%9/640.1406 3.57 1-3/41.7500 45.48 2-7/82.8750 74.06 4.00 43757.36%5/320.1562 3.97 22.0000 51.95 3-1/83.1250 80.52 4.50 47804.76%11/640.1719 4.37 2-1/82.1250 55.24 3-1/43.2500 83.81 4.80 52864.97%3/160.1875 4.76 2-5/162.3125 60.11 3-1/23.5000 90.28 5.00 52868.80%13/640.2031 5.16 2-7/162.4375 63.40 3-5/83.6250 93.57 5.50 57934.15%7/320.2188 5.56 2-1/22.5000 65.11 3-3/43.7500 96.86 6.00 57937.68%15/640.2344 5.95 2-5/82.6250 68.40 3-7/83.8750 100.15 6.50 631012.41%1/40.2500 6.35 2-3/42.7500 71.69 44.0000 103.44 6.80 69109-2.09%17/640.2656 6.75 2-7/82.8750 74.97 4-1/84.1250 106.72 7.00 691090.93%9/320.2812 7.14 2-15/162.9375 76.68 4-1/44.2500 110.01 7.50 691093.95%19/640.2969 7.54 3-1/163.0625 79.97 4-3/84.3750 113.30 8.00 75117-0.35%5/160.3125 7.94 3-3/163.1875 83.26 4-1/24.5000 116.59 8.50 751172.46%21/640.3281 8.33 3-5/163.3125 86.55 4-5/84.6250 119.88 8.80 81125-1.46%11/320.3438 8.73 3-7/163.4375 89.84 4-3/44.7500 123.17 9.00 811251.17%23/640.3594 9.13 3-1/23.5000 91.54 4-7/84.8750 126.46 9.50 811253.80%3/80.3750 9.53 3-5/83.6250 94.83 55.0000 129.75 10.00 871330.03%25/640.3906 9.92 3-3/43.7500 98.12 5-1/85.1250 133.04 10.20 871332.51%13/320.4062 10.32 3-7/83.8750 101.41 5-1/45.2500 136.33 10.50 871334.98%27/640.4219 10.72 3-15/163.9375 103.11 5-3/85.3750 139.62 11.00 941420.64%7/160.4375 11.11 4-1/164.0625 106.40 5-1/25.5000 142.91 11.50 941422.96%29/640.4531 11.51 4-3/164.1875 109.69 5-5/85.6250 146.20 12.00 101151-1.00%15/320.4688 11.91 4-5/164.3125 112.98 5-3/45.7500 149.49 12.50 1011511.18%31/640.4844 12.30 4-3/84.3750 114.68 5-7/85.8750 152.78 13.00 1011513.36%1/20.5000 12.70 4-1/24.5000 117.97 66.0000 156.07 

Better chip ejection in low carbon, non-ferrous materials.  They have good centering properties and requiers little pressure.  Heavy duty, d ≧ 3mm, 135° split point

#Cutting tools#-#Hole making tool#  

#Twist drill# is the most commonly used hole making tool. This kind of drill has a long linear main cutting edge. The two main cutting edges are connected by a cross edge and the chip groove is spiral shape (to facilitate chip removal).  

Part of the spiral groove constitutes the front cutter face, and the front cutter face and the top Angle determine the size of the front Angle. Therefore, the front Angle of drilling tip is not only closely related to the helix Angle, but also affected by the Angle of edge. 

The helix angle of ordinary twist drills mainly affects the size of the rake angle on the cutting edge, the strength of the blade blade and the chip removal performance, usually 25° to 32°. The spiral groove can be processed by milling, grinding, hot rolling or hot extrusion, and the front end of the drill bit is sharpened to form a cutting part. The apex angle of the cutting part of the standard ordinary twist drill is 118°, the bevel angle of the chisel edge is 40°-60°, and the relief angle is 8°-20°. Due to structural reasons, the rake angle is large at the outer edge and gradually decreases towards the middle, and the chisel edge has a negative rake angle (up to -55°), which acts as a squeeze during drilling. In order to improve the cutting performance of the twist drill, the cutting part can be ground into various shapes(such as group drills) according to the nature of the processed material. The shank of the twist drill has two types: straight shank and tapered shank. During processing, the former is clamped in the drill chuck, and the latter is inserted in the tapered hole of the machine tool spindle or tailstock. General twist drills are made of high speed steel. Twist drills with welded carbide blades or crowns are suitable for processing cast iron, hardened steel and non-metallic materials, etc. Small solid carbide twist drills are used for processing instrument parts and printed circuit boards.