1、UDC 62-229.31 : 621.9 DEUTSCHE NORM September 1982 Mach i ne tools 60“ centre holes Dimension i ng DIN 332 Part 7 Werkzeugmaschinen; Zentrierbohrungen 60“; Bestimmungsverfahren In keeping with current practice in standards published b y the International Organization for Standardization /SO), a comm
2、a has been used throughout as the decimal marker. Supersedes November 1977 edition 1 Scope and field of application This standard applies to the determination of the required size (dl ) of a 60 centre hole as specified in DIN 332 Part 1 for types A, i3 and C up to a maximum mass of workpiece of 28 O
3、00 kg. In the case of type R, it is recommended that, compared with d, as determined in accordance with this standard, the next larger size be chosen. Adequate lubrication of steel parts is assumed for fixed centres. For live centres, their speed-dependent loadbearing capacity shall be taken into ac
4、count, namely with regard to the axial force FA = 0,58 . Fto and to the radial force FR = Ftod, where Ftoa = FG + Fs (see equation (I). The method of dimensioning only applies on the assumption that 0 is not less than 3 or 0 is not less than 6,3. The size of the centre hole shall be chosen in accord
5、ance with this relation- ship. In critical cases, the existing manufacturing data are to be checked. Oversizing and undersizing can be avoided in this way. d2 dl 2 Determination of d Machining of the parts to be turned can take place with or without supports (steadies). - between centres - between c
6、huck and centre, 2.1 Equation for determining dl Contour of unmachined workpiece where d, FGi is the first nominal dimension (size) of the centre hole, in mm; is the weight force component, in N, which exists at the centre hole (for example in the case of symmetrical turned parts, FG1 = FG = -, wher
7、e FG is the weight force of the workpiece, in N; see note on subclause 2.2); Fs is the cutting force, in N, where Fs = 2,5. q . R,; q2) is the cross section of chip, in mm2, where q = depth of cut multiplied by the feed; R, is the tensile strength of the machined material, in N/mm2; R,02 is the 0,2
8、% proof stress of the machined material, in N/mm2 (RPo2 S is a safety factor (on the average, S = 1,75). FG 2 0,6 . Rm); I ) In the interest of greater safety, the cutting force Fs and the weight force component FG have been added in equation (1). Definition given in DIN 6580. Continued on pages 2 t
9、o 8 Beuth Verlag GmbH. Berlin 30. has exclusive sale rights for German Standards (DIN-Normen) DIN 332 ?art 7 Engl. Price group 7 03.85 Sales No.0107 Page 2 DIN 332 Part 7 2.2 Determination of dl as a function of R,os, q, FG or m For Rp02 over 180 up to 280 N/mm2, to be determined in accordance with
10、table 1; for K,02 over 280 up to 450 N/mm2, to be determined in accordance with table 2; for Rpo2 over 450 up to 710 N/mm*, to be determined in accordance with table 3; for Rp02 over 710 up to 1120 N/mm2, to be determined in accordance with table 4. Note.The dl value shall also apply for asymmetrica
11、l turned parts up to a ratio of cutting force Fs weight force FG k, = 2 4. For smaller hF values, the d, value to be chosen for the heavier end of the turned part shall be the next higher increment. This value then allows for imbalances of where Fe1 + FG2 = FG. FG1 8 FG2 -=- Example of the use of th
12、e tables Value sought: dl . Given: proof stress of workpiece material R, 02 = 250 N/mm2; mass of workpiece m = 1000 kg; chip section q = mm2. Result : from table 1, page 3 follows dl = 12,5 mm. DIN 332 Part 7 Page 3 w C O m al - L O 1 u- - cn .- E al 2 5 P E C .- W c al U m VI al 3 m E - al al 5 y.
13、O c C 3 u m al Y m c al C a o .- - 5 d - x VI al S m 5 al r c U C m - P c w O o a P c o al . .- u7 .- 5 -0, E + n c .- al c C O - E m a S .- E E C .- - U O c P J Q O L y. gz = - .- L 5 al 8 O P 3 4- 2 r- i N I“ I“ m. I !“ 7 2 i 1% I- - a;“ to- c Page 4 DIN 332 Part 7 E E C .- O Q J c y“- I 2s if mu
14、m. types R, A, B and C DIN 6580 Terminology used in cutting practice; motions and geometry of the cutting process I Solger, H. Bestimmung der erforderlichen Grsse einer 60-Zentrierbohrung (Determining the required size of a 60 centre hole), DIN-Mitteilungen (DIN News) 53 (1 974) 6, pp. 244 to 248. O
15、ther relevant standards DIN 332 Part 8 Type S 90“ centre holes; dimensions, method of determination Previous editions DIN 332 Part 7: 11.77 Amendments The following amendments have been made in comparison with the November 1977 edition: a) The subtitle “Determination of size“ has been changed into “
16、Dimensioning“. b) The standard has been editorially revised and aligned with DIN 820. Page 8 DIN 332 Part 7 0,8 1 Explanatory notes On the basis of inquiries made in writing, Subcommittee UA 12.3 of the Normenausschuss Werkzeugmaschinen (Machine Tools Standards Committee) unanimously decided to adop
17、t the contents of Preliminary Standard DIN 332 Part 7, November 1977 edition, as a definitive standard without amendments. In DIN 332 Part 1 values of weight force of turned parts to be machined between centr$s were not specified. Efforts to specify such values had been made repeatedly in earlier ye
18、ars. Studies relating to the 60 centre holes were started, since the 60 angle was considered to be adequate for most applications, in conformity with DIN 332 Part 1. In the report on the investigations made (1) all those factors are given which have a bearing on the machining of the workpieces and w
19、hich should be taken into consideration. The investigations have been presented in various papers given to working groups of DIN. On the basis of this, a number of companies have proposed the adoption, by the Normenausschuss Werkzeug- maschinen, of the results of the investigations as a DIN Standard
20、. This has been the purpose of the present standard. If requirements for the value of d, are given on already existing older drawings, deviations therefrom may be accepted within the range of f 1 increment (the factor between two subsequent increments being 1,25), in comparison with the values deter
21、mined in accordance with tables 1 to 4. The following table shows the rearrangement of the hitherto existing centre hole specifications associated with DIN 332 Part 1 (in its factual content in accordance with the specifications of IS0 866 - 1975). 2 1 x 2,12 2.5 1.25 X 2.65 Dimensions in mm I DIN 3
22、32 Part 1 1 4 5 I i 10 5 X 10.6 12,5 6.3 X 13.2 September 1960x November 1973 edition edition dl I d2 1 dt Xd2 63 16 8 X 17 8 20 10 x21,2 10 25 12,5 X 26,5 4 0.8 X 1.7 1 1 1 :,6 1 2,5 X 5,3 2.5 63 3,15X 6,7 3.15 . 4 X 8.5 A column has been added for the previously used dimension ci2, in order to enable, using the most important functional dimension, a comparison between the previous and new designations or dimensions. This has not been possible with the hitherto used nominal dimension d,. International Patent Classification 0 23 B 35/00
