Общий каталог Tungaloy 2020 - 2021 - страница 1658

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Parts for ToolsTechnicalReference User’s Guide - Technical Reference Drilling To o l s Regrinding method [Applied to DSW] Please refer to the following instructions prior to regrinding DSW type drills. Before regrinding Check the cutting edge for damage and wear. If any large fracture is found, remove with a silicon carbide wheel. (1) Grinding the flank Fig. 1 Grinding relief angle ᭹ Use a 280 to 400 grit diamond cup type wheel of 100 ~ 200 mm in diameter. Point angleθ1° 1) Grind the relief surface so that primary relief angle (θ) of 2° can be formed as shown in Fig.1. After grinding the other C side likewise, do sparkout grinding so that the difference of the lip height will be kept within0.02 mm. Primary Secondary Primary reliefreliefreliefθ2°angle 2) In the cases of DSW types: After grinding the primary relief Viewed from C. angle (θ) 2°, without rotating the drill, grind the secondary relief surface so that the relief angle (θ) of 3° can be formed. In the same way as 2), take care to bring the ridge line A formed between the primary and secondary relief surfaces B Secondary to the drill center. (Values (θ) of 1° ~ 3° are shown in Table 1) Using points A and B as θ3° relief angle reference, obtain level. Viewed from C. (2) Thinning θ1 θ2 θ3 • Use a 280 ~ 400 grit diamond straight-type wheel of 100 ~ 200 Table 1 (Primary relief (Secondary relief mm in diameter. (Point angle) angle) angle) • Conduct thinning in the same manner as cross thinning (X-type). DSW –20° –6° ~ –12° –23° ~ –27° • Values of β1 to β3 written in the figures are given in the Table 2. Table 2 β1 β2 β3 DSW 147° ~ 153° 30° ~ 42° 95° ~ 110° Fig. 2 β2 β1 0 β3 (3) Honing • The honing angle θ and width H should be varied depending on the drill type, diameter, and work material. Recommended honing specifications are given in the Table below. • Honing procedures (refer to Fig.3) (1) Round the R portion shown in Fig.3 in large. (2) Then, roughly hone the cutting edge lines by using an electro-deposited diamond file of around 170 grit. (3) Carry out finish honing by using a diamond hand stick of 400 to 600 grit. • The honing width should be changed depending on the drill diameter. For smaller side of diameters, the width should be in smaller side of values given in the Table. • Angle honing ~ ø6 mm ø6 ~ ø10 mm ø10 ~ ø16 mm θ - 20º - 20º - 20º H 0.03 ~ 0.05 0.05 ~ 0.08 0.08 ~ 0.1 • R Honing Fig.3 Dimensions (mm) R HoningR (mm)DC ) ø60.02 ~ 0.04ø6 < DC ) ø160.03 ~ 0.05 R Honing Width HRRakeAnglefaceAngleRake faceAARelief surfaceθRelief surface R Honing Angle Honing After regrinding, check the following before use. （A-A section） （A-A section） Notes: • The difference of the lip height is kept within 0.02 mm. • For more details on regrinding, consult the nearest Tungaloy sales office. • Any damaged portion on the cutting edges is not left. • Cutting edges are properly honed. • Any grinding burr is not left. L070 www.tungaloy.com