1、, 1 I ! UDC 62-272.272 DEUTSCHE NORMEN nay 1973 Helical Springa Made of Round Wire Quality Specifications for Cold Coiled Tension Springs 2097 Zylindrische Schraubenfedern aus runden DIhtm; Outevorschriften fr kaltgefomte Zugfedern This Standard applies to cold coiled tension springs made of patente
2、d-drawn or heat treated spring wires up to wire diameter when severe stressing is involved, tension springs may be hot coiled without initial tension from dram or rolled non-heat-treated spring rires, and heat treated after coil- ing. The latter method is rarely used and therefore no tolerances for
3、it are specified. If required, information can be obtained from the spring manufacturer. The materials listed in Section 3.6 and the undeXWIentioned limiting values also apply to this Standard: 17 mm wire diameter. Over 17 mm wire diameter and from as little as lo mm Hean coil diameter Dm to 160 rn
4、Number of working coils if p 3 Free length of spring to 1500 mm Coiling ratio w4toX) 1. - Dimensions in mm Represent at ion Figure I. Tension spring 2. Formula symbols. dimension 1ettera.denominations and units a, Quantity used for determining the variations for loop position (effect of coiling rati
5、o and number of coils) in O ap Wantity used for determining variations of load and spring length (effect OP geometry and imensions) in N c - Spring rate in mm d Wire diameter in mm Nominal dimension of wire diameter according to DIN 2076 or DIIJ 1757 increased by the upper allowance in mm Total numb
6、er of coils if Number of working coils i g Factor used for determining variations of load and spring length (effect of working m Hook opening in mm s1 ta sn Deflections correeponding to loads Pl to Fn W - 7 coiling ratio k f coils) % Permissible variation of loop position of unloaded spring Pennisai
7、ble Variation of coil diameter (Da, Di, Dn) of unloaded spring in mm Permissible variation of load F at given spring length L in B in O AO ID IF Continued on pages 2 to i0 Explanationa on page 10 Alleinverkauf der Normbltter durdi Beuth Verlag GmbH, Berlin 30 und Kln i Dm 2097 engl. Preisgr. Page 2
8、Dm 2097 euality grade 1 0,5 d 0,75 d 3.3. Loop or hook openings and exact total For springs with loope according to Figures 2 to 9 and 14, the total number of coils ig is fixed by the position of the loops (Figure 15). - - - -_- . E?!ker-oi-c!2il8 Wg12 Permissible variation of length Lo of unloaded
9、8pring in mm Outside coil diameter in mm Inside coil diameter in mm in mm Di Dm BO I “k;- mean coil diameter Initial tension imparted during coiling in I lengths LI to Ln in B Dietance from inside of FI to In Loads corresponding to spring IIr loop to bob of spring in mm Quality Quality grade 2 grade
10、 3 d 2d + 1,5d I 3d - Length of unloaded body of spring with initial teneion Free length of spring, measured to inside of loops load F, in mm %I in ma in mm LI )Lg + Am length at minimum test In a simplified view - disregarding the deflec- tion of the loops - ig I i . w 12 L to L Lengths of loaded s
11、pring measured to inside of loopa, correeponding to loads FI to Fn Q Coefficient of quality grade by agreement with the manufacturer - in mm DIN DIN 2s7s_s_fBce,nrn48c4roo The springs are usually protected by oiling or greasing. Other foms of corrosion protection are to be agreed with the manufactur
12、er. DI 297 Page 3 I Figure 2. Open loop $ = 0.55 Di to 0.8 Di Figure 4. Double loop % 0.8 Di to 1.1 Di I Figure 5. Full loop at ride - Di I Figure 6. Double loop at aide - Di Figure 7. Baired hook Figure 8. Baieed hook at aide Figure 9. Full loop with offret % - 7.1 Di Bigure IO. Swivel hook Figure
13、11. Rolled-in stud Myre 12. Threaded lut3 engadrig 2 to 4 colin Jigure 13. mead-on plata angaglm 2 to 4 coiln rigure 14. Angled fll loop i _ - _- Bigurs 15. Host commonly used poeitionr of loop opining8 and the related data regarding total number of coils. (To be entered in Proforma B according to D
14、M 2099 Part 2, Item 3). DIU 2097 Page 5 0.63 1 1,6 295 4 6,s 10 16 25 31.5 40 50 63 80 100 125 4. Quality r(i des. Demissible variationg The quality grades I, 2 and 3 are specified (for coeficienti Q see Table 2). All the pedssible variations listed below apply only to iateria1 Group I. Por material
15、 Group 2, pezriisible variations are to be agreed between ianufacturer and user. The choice between qualitj grades I, 2 and 3 will be governed br the du9 requirements. The qualit7 grade required and the penissible variations are to be expreielj agreed or stated in the drawing preprint (see also DM 2
16、099 Part 2). In the absence of inoraation to this effect. auality grade 2 shall In the interest8 of ratio-lized wufactlir qualitJr grade 7 should be specified only when the particular application calls for it. For this pu to 4.5 neceesarily belong to a mingle quality grade.% variations sialler thsn
17、“I“ are required, agreement to this effect must be reached with the manufacturer. Accoring to DIX 2076 Round spring wire; dimensions, weighte, periissible variations (also ose not i11 the sites In Sections 4.1 4:l:-oe_noieeolo-oo-,o4looa_orwlro_a-ile p- plies to spring wire of wrought copper alloys
18、according to DiTi 176827 Dm 1757 Wire of copper and wrought copper alloys, dram; dimensions 4.2. Parniissible variations Ap_for coil diameter of unloaded See Table I. . - 1 196 295 4 6.3 10 16 25 31,5 40 50 63 80 100 125 160 In drawings and in enquiry and order documents only the important coil diam
19、eter should be stated. The permissible variations specified for Dm apply both to the corresponding iametere Di and to D When-coiling ratios are larger than w I 20, agreement ehall be regarding diameter tolerances. reached with the manufacturer Table I. I 1 Pemimiblo variations in u I Quality mads 1
20、Quality grado 2 Quality grade 3 I Dm I uith coiling ratio u I uith coiling ratio w I with coiling ratio w I abovo I up to i 0,05 2 0,07 20,l i 0.07 i 0,l i 0,05 I0,07 i 0,l 2 0,08 i0,l 20,07 I0,l i0,15 i0,l 20,15 20,l I0,l ?0,15 -+ 0.15 20.2 i0,l 20,15 i0,2 2 0,2 i 0,25 2 0,15 IOJ5 i0,2 i0,25 i0,3 2
21、0,15 iO,2 20,25 20.3 2 0.35 i 0.2 i 0,25 i 0,3 i 0,35 20.45 i: 0,25 i0,3 20.35 i 0,4 I 0,5 I 0,35 i 0,5 i 0.6 i 0,8 i 0,9 - 2 0,5 i 0,6 i 0,8 I l,o i 1,2 f 1,4 2 0,6 i 0,8 t l,o i 1,2 i 1.5 f 1,9 aboro 14 4 to8 UP to20 i 0,3 I 0,4 i 0.5 I 0,7 i 0.6 2 0,s I 0,7 2 l,o i 0,9 i 1,2 2 1.1 i 1.5 i 1,4 i 1
22、,8 2 1.7 i 2,3 i 2,2 t 2.8 2 2,7 i 3,5 abro 8 I above 14 I rip to14 up to 20 2 0,4 i 0,5 2 0,5 i 0,6 2 0,6 2 0,7 2 0.7 i 0.8 I 0,9 2 l,o -I- i l,o .i 1.2 2 1,2 f 1.5 -+ 1,5 2 1,s i 2.0 i 2.3 i 2,4 I 2,8 2 3.0 i 3,5 r i 3.7 -+ 4,4 i 4,6 I 25.4 Page 6 DIn 2097 Dm inmm - Figure 16. Quantity aF Influenc
23、e of geometry ana aimensione on variations of load and epring length for wire diameters from 0.07 to 1.1 mm 4:Zt_oermissible_arlai-Oof_looo_P_at_sioeo gpi-t- dimensions DM 2076 Round s ring wire; dimensions, weits, pedssible variations DIl 2089 DIN 2095 DIN 2096 Helical springs made of round bar ste
24、el; quality specifications for compression Part 2 TPreliminarg Standard) Helical springe made of round wire and rod; calcula- tion and deeign of tenaion springs Helical springs made of round wire; quality specifications for cold coiled compression springs springe quenched and tempered after coiling
25、Part 2 Helical springs made of round wire; information on tension springs; form Part 1 Round spring steel wire, quality apecifications; patented dram spring wire DIN 2099 DIN 17223 made of unallojed steels Part 2 -: quenched and tempered spring vire and quenched and tampered valve spring DIN 17223 -
26、 wire made f unallqed steels DIN 17224 (Preliminary Standard) Stainless steel wire and strip for apdngs, quality speci- f ications DIN 17225 (Preliminary Standard) High-temperature steels for springs, quality properties DM 17672 Part 7 Rod, bar and wire of copper and wrought copper alloys, atrength
27、properties DIN 17672 Part 2 -; technical conditions of delivery DM 17682 Round spring wire of wrought copper allogs; strength properties, technical condi- tions of delivery Explmntions This Standard contains the agreement reached in the present state of the art betveen the industrial interests conce
28、rned in respect of the design and testing of cold coiled tension spring6 and the require- ments to be met by such aprings. Quality grades 1. 2 and 3 are distinguished, the permissible variationa being, for quality grade 1, 0.63 times thos. of the medium quality grade 2, whilst for quality grade 3 th
29、ey are 1.6 times those of grade 2. Tension oprings vith load aud length variations corresponding to quality grade 1 cau be made with an average 1 % rejection rate by a manufacturer using normal production resources and the measuring method6 in use at the preient tine. Spring of this kind must be 100
30、 $ teetad and this entails increased expenditure in production. Quality grade 2 should therefore be specified a6 preferred because this grade can be guaranteed by adopting properly organized in-manufacture spot testing instead of 100 $ testing. Quality grade 2 rill usually yield the most favourable
31、cost-qudity ratio. Over M extended period of time a joint operation has been conducted for the inveotigation and statistical evaluation of variationa in load arising in production. According to this York, tho permissible variation in load is a function of the spring dimencions h. d, if and F. The mo
32、de of dependenc. established for teMion springe appliee similarly to compression springs (cf. DIN 2095). There is also a connection via the spring rate between load and length variations of tension springs vithout initial tenmion. The quality grades and permissible variations according to this Stand
33、ard differ from those of th. earlier ianue. The quality grade designations 1, 2 and 3 have therefore been nevly introduced. In line with existing basic standarde the following formula syubols hare been amended: F Load (formerly P) and e Deflection (formerly i). Tho statutory unit of force Newton (N)
34、 has been specified instead of the kilopond (kp). (Conversion: exact rounded 1 kp = 9.80665 N. 1 kp =a 10 N). Further amendments compared with the earlier issue are the re-specifying of the determination of ADDI Ao and Am for teneion springe wound with initial teneion. Doubt often arises in practice regarding the fora of loop and the number of coils in conjunction with the relative position of the loop openings, and therefore information on these points has been included in Sections 3.2 and 3.3.
