1、Technical delivery conditions for DIN 6537 and DIN 6539 solid hardmetal twist drills Checking of dimensions Technische Lieferbedingungen fr Vollhartmetall-Spiralbohrer nach DIN 6537 und DIN 6539; Prfung - DIN 6540 - Part 2 In keeping with current practice in standards published by the International
2、Organization for Standardization (ISO), a comma has been used throughout as the decimal marke,: Dimensions in mm Contents Page 1 Scope and field of application . 1 2 Checking of dimensions 2.1 Cutter diameter and back taper . 2.2 Radial run-out . 2.3 Relative lip height 3 Surface roughness . 1 Scope
3、 and field of application This standard specifies methods of testing solid hard- metal twist drills as specified in DIN 6537 and DIN 6539. See DIN 6540 Part 1 for quantities, symbols, units and requirements. Terminology and symbols used in the field of chip removal are covered in DIN 6581 and DIN 65
4、82. 2 Check of dimensions 2.1 The cutter diameter. d, shall be measured across the outer corners of the drill, as shown in figure 1, and the back taper, across the lands at the outer corners. Cutter diameter and back taper 1 Figure 1 : Point of cutter diameter measurement 2.2 Radial run-out The radi
5、al run-out shall be measured on the lands, at a distance of about 1,5 mm from the outer corners, using . I . I I 2 n L a suitable vee block with stop and dial gauge, as shown in figure 2, or other optical measuring instru- ments. The drill shank shall be placed on a vee block so that it is in contac
6、t with the stop (magnet). The drill shall be turned until the land is directly below the stylus. With the gauge in zero position, the stylus shall be brought into contact with the land close to the outer corner. The drill shall be rotated through an angle equal to 360“ divided by the number .of cutt
7、ing edges until the stylus touches the next land, and the reading taken. After taking measurements at three lands, the maximum indicated value shall be taken as the radial run-out value. Figure 2: Measurement of the radial run-out of parallel shank twist drills Continued on page 2. Beuth Verlag GmbH
8、, Berlin, has the exclusive right of sale for German Standards (DIN-Normen). DIN 6540 Part 2 Engl. Price group 6 08.95 Sales NO. 0106 Page 2 DIN 6540 Part 2 2.3 Relative lip height The relative lip height, As, shall be measured close to the centre of the major cutting edge, excluding the area of web
9、 thickness reduction, by means of a vee block with stop and a dial gauge located perpendicular to the nominal position of the major cutting edge (see figure 3). 3 Surface roughness The conditions for measurement of the surface rough- ness value, Ra (arithmetical mean deviation of the profile), shall
10、 be as specified in the following table. A Figure 3: Set-up for measuring lip height The drill shank shall be placed on a vee block so that it is in contact with the stop. With the gauge in zero position, the stylus shall be brought into contact with the drill close to centre of the major cutting ed
11、ge (posi- tion No. 1 shown in figure 4). The drill shall be rotated through an angle equal to 360“ divided by the number of cutting edges and the reading taken for the other major cutting edges (position No. 2 shown in figure 4). The difference between the largest and the smallest value measured for
12、 all the cutting edges shall be taken as the lip height, As. 1 2 Table Cutter diameter Evaluation measured, in mm length, cut-off) Over 1 Up to 1 z:?: 6,OO I 0,48 I 0,08 I 20,oo 1,50 0,25 I) For definition, see subclause 2.1 of DIN 4768, May 1990 edition. Ra shall be measured at the following points
13、: a) in the flute, at right angles to the side rake, yf, for measurement 1, at a distance equal to one cut- ter diameter from the point, for measurement 2, at mid-length of the flute; b) on the flank, across the grinding direction, close to the major cutting edge; c) on the flank, in axial direction
14、, close to the major cutting edge; d) on the shank. When measuring in the flute (point of measurement a), the evaluation length shall not extend beyond the minor cutting edge and when measuring on the flank (point of measurement c), axial measurement shall be carried out towards the drill point or t
15、he shank. Measurement on the shank (point of measurement d) shall be carried out axially. The evaluation length as a function of cutter diameter shall be as specified in the table. Figure 4: Point of lip height measurement Standards referred to DIN 4768 DIN 6537 DIN 6539 DIN 6540 Part 1 DIN 6581 DIN
16、 6582 Determination of surface roughness parameters Ra, R, and R, with electric stylus instruments; concepts and measuring conditions Stepped parallel shank solid hardmetal twist drills; dimensions Continuous parallel shank solid hardmetal twist drills; dimensions Technical delivery conditions for D
17、IN 6537 and DIN 6539 solid hardmetal twist drills; requirements Concepts associated with chip removal; reference systems and angles on the cutting of tools Concepts associated with chip removal; additional concepts for tool, wedge and cutting edge Other relevant standard DIN 6580 Concepts associated with chip removal; movements and geometry of the chip removal process International Patent Classification 6 23 B 051 /O0 6 27 G 015/00 B 28 D O01 /14 G O1 B 003/22
