1、c ._ - m m IS0 metric coarse and fine pitch screw threads diameters from 5mm to 16mm for interference fits in aluminium cast alloys with 3 g. 2: DIN 8141 L 5 a o o z Nominal sizes, tolerances and limits of size I Part 1 Metrisches ISO-Gewinde; Regel- und Feingewinde fr Festsitz in Aluminium-GuBlegie
2、rungen; Gewinde-Nenndurchmesser von 5 bis 16 mm; Nennmae, Toleranzen und Grenzmae In keeping with current practice in standards published by the International Organization for Standardization (ISO), a comma has been used throughout as the decimal marker. Dimensions in mm 1 Scope and field of applica
3、tion This standard applies to IS0 metric screw threads having the basic profile specified in DIN 13 Part 19 which are intended for interference fits between steel bolts, screws and studs (external thread) of property classes up to 10.9 as specified in DIN EN 20 898 Part 1 and holes (internal thread)
4、 in aluminium cast alloy components. It specifies maximum and minimum material profiles, nominal sizes, fundamental deviations, tolerances and limits of size of internal and external threads and gives details regarding the surface protection of external threads. Jointing threads in accordance with t
5、his standard are threads where pressure-tight joints are not made on the threads. This standard does not cover internal threads in steel or grey cast iron components (see Explanatory notes). For gauges for internal and external threads, see DIN 8141 Part 2. 2 Concepts For concepts associated with sc
6、rew threads, see DIN 2244. 3 Basic profile r P I Internal thread I l w i a a 4- ._ m o D m S - .- Z UDC 621.88.082.131 : 621.713.1 DEUTSCHE NORM July 1993 -. Sales No.0107 10.95 I i d “1 Figure 1 : Thread profile of internal and external threads Continued on pages 2 to 5. ith Verlag GmbH, Berlin. ha
7、s the exclusive right of sale for German Standards (DIN-Normen). DIN 8141 Part 1 Engl. Price group Page 2 DIN 8141 Part 1 TD, TDi, TD2 Td, Td2, Td3 Table 1 : Symbols and dimensions Pitch diameter Tolerances on thread diameters D, DI, D2, d, d2 and d3 d d2 d3 external thread Major diameter Pitch diam
8、eter Minor diameter I es Upper deviation external thread 4 Dimensions and designation 4.1 Nominal sizes 4.1.1 Coarse pitch threads As in DIN 13 Part 1. 4.1.2 Fine pitch threads For P = 1 and 1,25 mm, see DIN 13 Part 5 and for P = 1,5 mm, see DIN 13 Part 6. 4.2 Fundamental deviations The fundamental
9、deviations for internal and external threads shall be as specified in table 2. Table 2: Fundamental deviations of internal and external threads values in pm Internal thread External thread I I I Deviations P, in mm for O d -1 10 -1 35 -1 62 -1 76 -1 98 -209 -24 -26 -28 -32 -34 -38 I Internal thread
10、+ v Nominal size c O a .- .- 80 n - I External thread Figure 2: Illustration of position of tolerance zones and tolerance Ton pitch and minor diameters + v Nominal size External thread lFb1 Internal thread Figure 3: Illustration of position of tolerance zones and tolerance Ton major diameters 4.3 Le
11、ngths of thread engagement As a function of the property class, the studs shown in fig- ures 4 and 5 shall have the following lengths of engagement, I: for studs of property class 8.8 or less, at least twice the nominal thread diameter; for studs of property class 10.9 or less, at least 2,5 times th
12、e nominal thread diameter. To facilitate tightening, studs with incomplete thread (see figure 4) shall be provided with ends of equal thread size produced to this standard. DIN 8141 Part 1 Page 3 I Designation DIN number - 95 106 119 126 u 1 60 118 265 50 166 180 132 190 190 140 198 335 200 67 1 50
13、21 7 375 21 2 71 1 60 237 300 60 5 Tolerances Tolerances and limits of size shall be as specified in tables 3 and 4. Table 3: Tolerances on internal and external threads Values in pm Nominal thread diameter, in mm 5 6,7,8 and 10 12 and 16 Pitch, in mm 8,9and 10 I 1,25 1,5 12,14 and 16 E 14 and 16 68
14、 I 200 I 125 I 40 I 95 I 126 6 Coated external threads The thickness of coatings on external threads shall not exceed 1/4 of the fundamental deviation es for the pitch diameter, dp. The specifications of DIN 13 Part 14 for 69 coated threads shall apply to the pitch diameter and the minor diameter of
15、 external threads (prior to coating). For the major diameter of external threads, the maximum value given in table 4 shall not be exceeded. Page 4 DIN 8141 Part 1 .a“- $ .E N 2 x rn 5 .- EN .- 5 .n“- 5 .E N 2 Ca x rn 5 .E .4 Ca 5 5 .E w x rn I m 5 .- EN .- sa 5 a- 44G4 h h h h f-coma DIN 8141 Part 1
16、 Page 5 Standards referred to DIN 13 Part 1 DIN 13 Pari 5 DIN 13 Part 6 DIN 13 Part 14 DIN 13 Part 19 DIN 267 Part 15 DIN 2244 Screw threads; terminology DIN 8141 Part 2 DIN EN 20 898 Part 1 IS0 metric screw threads; 1 mm to 68 mm diameter coarse pitch threads; nominal sizes IS0 metric screw threads
17、; 1 mm and 1,25mm fine pitch threads with diameters from 7,5mm to 200 mm; nominal sizes IS0 metric screw threads; 1,5 mm fine pitch threads with diameters from 12 mm to 300 mm; nominal sizes IS0 metric screw threads; tolerance system for threads 1 mm in diameter and larger IS0 metric screw threads;
18、basic profile and manufacturing profiles Fasteners; technical delivery conditions; prevailing torque type nuts IS0 metric coarse and fine pitch screw threads for interference fits in aluminium cast alloys with diam- eters from 5 to 16 mm; gauges for internal and external threads Mechanical propertie
19、s of fasteners; bolts, screws and studs (IS0 898-1 :1988) Other relevant standards DIN 13 Pari 51 IS0 metric screw threads; external threads for transition fits; tolerances, limit deviations and limits of size Explanatory notes It should be noted that the tolerances on the pitch diameter of external
20、 threads as specified in DIN 13 Part 51 do not result in a tight fit but, depending on the actual size of the external and internal threads within the particular tolerance zone, mostly in a clearance fit (cf. Kbler, K.-H. Festsitzgewinde, ein Mrchen? (Interference fit thread, a fairy tale?), Verbind
21、ungstechnik 1979: 14 (6), 31, 32). This was the reason why the responsible committee decided to prepare this standard. A tight fit cannot be achieved by an interference in the pitch diameter, since the tolerance on the pitch diameter cannot be decreased at will. As an alternative, preference was giv
22、en to an interference fit which has often proved advantageous in auto- motive engineering where a tight fit is achieved by an actual interference of metal between external and internal threads. Interference is so designed that at the minimum limit of size the stripping torque of the bolt exceeds tha
23、t of the prevailing torque type nut (cf. DIN 267 Part 15) and no cold shut occurs at the maximum limit of size. The advantage of this is that the pitch and minor diameters comply with the standards for IS0 metric screw threads and that the major diameter of the internal thread can be manufactured wi
24、th commercial screwing taps ground flat at their external diameter. In order to keep deviation of the major diameter from that of IS0 metric screw threads as slight as possible, the lower deviation for tolerance 6h shall apply to the minimum major diameter. This ensures that the minimum flank overla
25、p is larger than required for fit 6H/6g, thus permitting studs to be assembled automatically, since both thread ends may be produced to the same thread limits of size. The thread sizes specified in this standard are suitable for nut threads in aluminium cast alloy components. An interference fit may
26、 be achieved in steel components with less interference, but could be problematic in producing grey cast iron components. Where the components of a threaded assembly are made of materials of different electrochemical potential (e. g. a combina- tion of steel studs with aluminium alloy internal threads), it may be necessary to take measures in order to preclude galvanic corrosion (e. g. by providing the stud thread with a suitable coating). International Patent Classification F 16 B O33102 F 16 B 035100 G O1 B 003140 G O1 B 003148 G O1 B 0051002
