BS 3821-3-1974 Specification for hardmetal dies and associated hardmetal tools - As-sintered pellets and finished dies for drawing round bar《硬质合金模具和配套硬质合金工具规范 第3部分 拉制圆棒材用烧结模坯和精加工模》.pdf

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1、BRITISH STANDARD BS3821-3: 1974 Specification for Hardmetal dies and associated hardmetal tools Part3: As-sintered pellets and finished dies for drawing round bar UDC 621.778.1.073:669.018.25+621.778.1.073:669422.11BS3821-3:1974 This BritishStandard, having been approved by the MechanicalEngineering

2、 IndustryStandards Committee,was published underthe authority of the Executive Board on 29July1974 BSI12-1999 The following BSI references relate to the work on this standard: Committee referenceMEE/155 Draft for comment72/33678DC ISBN 0 580 08152 4 Co-operating organizations The Mechanical Engineer

3、ing Industry Standards Committee, under whose supervision this BritishStandard was prepared, consists of representatives from the following Government departments and professional and industrial organizations: Associated Offices Technical Committee Department of Trade and Industry Association of Con

4、sulting Engineers NationalEngineering Laboratory Association of Hydraulic Equipment Electricity Supply Industry in England and Manufacturers Ltd. Wales Association of Mining Electrical and Engineering Equipment Users Association Mechanical Engineers Federation of Manufacturers of Construction Britis

5、h Compressed Air Society Equipment and Cranes British Electrical and Allied Manufacturers Institution of Civil Engineers Association Institution of Gas Engineers British Gas Corporation Institution of Heating and Ventilating British Gear Manufacturers Association Engineers British Internal Combustio

6、n Engine Institution of Mechanical Engineers* Manufacturers Association Institution of Plant Engineers British Mechanical Engineering Confederation Institution of Production Engineers British Pump Manufacturers Association London Transport Executive British Steel Industry* Machine Tool Trades Associ

7、ation Crown Agents for Oversea Governments and Ministry of Defence Administrations Ministry of Defence, Army Department Department of Employment National Coal Board (HMFactoryInspectorate) Process Plant Association Department of the Environment Railway Industry Association of Great Britain Departmen

8、t of Trade and Industry Royal Institute of British Architects EnergyTechnology Telecommunication Engineering and Department of Trade and Industry (Marine) Manufacturing Association The organizations marked with an asterisk in the above list, together with the following, were directly represented on

9、the committee entrusted with the preparation of this BritishStandard: British Non-ferrous Metals Federation Institute of Iron and Steel Wire Manufacturers High Conductivity Copper Group Individual experts British Hard Metal Association British Independent Steel Producers Association Amendments issue

10、d since publication Amd. No. Date of issue CommentsBS3821-3:1974 BSI 12-1999 i Contents Page Co-operating organizations Inside front cover Foreword ii 1 General 1 1.1 Scope 1 1.2 Definitions 1 1.3 Symbols 1 2 As-sintered pellet 1 2.1 Hardmetal grades 1 2.2 Forms and dimensions 1 3 Case 1 3.1 Materia

11、l 1 3.2 Forms and dimensions 1 4 Finished die 1 4.1 General requirement 1 4.2 Assembly 4 4.3 Accuracy 4 4.4 Marking 5 Appendix A Information to be supplied when ordering 8 Figure 1 Symbols for as-sintered pellets for drawing round bar 2 Figure 2 Symbols for finished dies for drawing round bar 3 Figu

12、re 3 Bar drawing dies for steel (reference letter C) 5 Figure 4 Bar drawing dies for non-ferrous metal (reference letter D) 7 Table 1 Dimensions and tolerances of as-sintered pellets 4 Table 2 Tolerance on diameter of bearing of pellet d 01 4 Table 3 Machining allowance on diameter of bearing of pel

13、let, d 01 4 Table 4 Dimensions of bar drawing dies for steel 6 Table 5 Dimensions of bar drawing dies for non-ferrous metal 7 Publications referred to Inside back coverBS3821-3:1974 ii BSI 12-1999 Foreword Prepared under the authority of the Mechanical Engineering Industry Standards Committee, this

14、Part of this BritishStandard takes into account the requirements of ISO Recommendation1684, “Wire, bar and tube drawing dies. Designation-Marking-Dimension” which deals with finished dies, and dimensions of as-sintered pellets. Part1 of this BritishStandard specifies designation and marking of as-si

15、ntered pellets and finished dies and Part2 of the standard specifies as-sintered pellets and finished dies for drawing round wire. Part2 of this standard revises and extends the scope of the1964 edition of BS3821. A British Standard does not purport to include all the necessary provisions of a contr

16、act. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to8, an inside back cover a

17、nd a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS3821-3:1974 BSI 12-1999 1 1 General 1.1 Scope This Part of this BritishStandard specifies as-sintered pellets and f

18、inished dies for drawing round bar from steel in the range9mm to61mm diameter and from non-ferrous metal within the range9mm to72mm diameter. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 1.2 Definitions For the purposes of this BritishStandard

19、the following definitions apply: 1.2.1 hardmetal sintered material characterized by high strength and wear resistance, with hard substances, e.g.carbides, of refractory metal, as the main component and with a metallic binder phase 1.2.2 pellet that component of a bar drawing die which is made from h

20、ardmetal. Prior to finishing it is usually termed the “as-sintered pellet” or “rough pellet” 1.2.3 case that component of a bar drawing die into which the pellet is positively fixed 1.2.4 bore the bore of the pellet including the entry, drawing, bearing and exit portions 1.2.5 finished die the assem

21、bly of the case and the pellet after all operations have been completed 1.2.6 nominal size the nominal size of the die: equal to the nominal size of the bar which it will produce 1.2.7 measured size the actual measured value of the bearing diameter 1.2.8 designating size the size of the die expresse

22、d as pellet diameter (d 2 ) case diameter (d 3 ) (See Table 4 and Table 5.) 1.3 Symbols For the purposes of this BritishStandard the symbols shown in Figure 1 and Figure 2 relate to the dimensions of as-sintered pellets and finished dies, respectively, for drawing round bar. 2 As-sintered pellet 2.1

23、 Hardmetal grades Pellets for bar drawing dies shall be manufactured in grades of hardmetal selected from BS4276. 2.2 Forms and dimensions The as-sintered pellet shall conform to the requirements of Table 1, Table 2 and Table 3 with respect to dimensions, tolerances and machining allowances (and See

24、 Figure 1). As-sintered pellets for drawing dies shall be identified as follows: Bar drawing dies for steel Reference letter C Bar drawing dies for non-ferrous metal Reference letter D 3 Case 3.1 Material The case shall be manufactured from material selected in accordance with the following: from st

25、eel complying with the requirements of BS970-1,080M40 1)or from steels equivalent or superior in mechanical properties. 3.2 Forms and dimensions The case shall conform to the requirements given in Table 4 or Table 5 as applicable (and see Figure 2, Figure 3 and Figure 4). The case may be of straight

26、 (code letter Z) or tapered (code letter K) form. When a tapered form is required, an included angle of2=10 shall be provided, in which event d 3is the diameter of the larger end of the taper. 4 Finished die 4.1 General requirement The finished die, consisting of hardmetal pellet and case, shall com

27、ply with the requirements specified in4.2 and4.3. 1) Steel080M40 was previously designated En8 in the superseded En series.BS3821-3:1974 2 BSI 12-1999 Figure 1 Symbols for as-sintered pellets for drawing round barBS3821-3:1974 BSI 12-1999 3 Figure 2 Symbols for finished dies for drawing round barBS3

28、821-3:1974 4 BSI 12-1999 Table 1 Dimensions and tolerances of as-sintered pellets Table 2 Tolerance on diameter of bearingofpellet, d 01 Table 3 Machining allowance on diameterofbearing of pellet, d 01 4.2 Assembly The pellet shall be positively and permanently fixed in its correct position in the c

29、ase. The method of fixing shall be such as to ensure adequate support to the peripheral face of the base of the pellet. 4.3 Accuracy 4.3.1 Roundness of bearing. Up to and including15.5mm diameter the maximum tolerable departure is54m. For diameters greater than15.50mm the maximum tolerable departure

30、 is104m. d 02 Tolerance on d 02 h 02 Tolerance on h 02 l 04 Maximum and minimum values of d 01 asuch that for finished dies one obtains: for steel bar (referenceletter C) for non-ferrous bar (reference letter D) d 1min d 1max d 1min d 1max mm mm mm mm mm mm mm mm 25 +0.7mm 20 5.0 9 12 30 35 40 +0.2m

31、m 24 5.5 9 12 15 13 16 19 11 13 17 14 18 21 45 50 25 0.4 6.0 18 21 22 25 20 24 25 28 55 60 65 27 6.5 24 27 29 28 31 34 27 30 34 32 36 40 70 75 80 1% 30 7.5 32 35 39 37 41 45 38 42 46 44 48 52 85 90 95 33 0.5 8.0 43 47 49 53 50 54 58 56 60 64 100 105 35 8.5 51 61 62 65 68 72 a d 01shall be determined

32、 when ordering, taking account of the minimum machining allowance: d 01= d 1 machining allowance (seeTable 3). d 01 Tolerance on d 01 a From Up to but not including mm mm mm 9 12 12 16 16 20 20 25 25 32 32 40 40 50 50 63 63 72 a The tolerance on d 01applies to the greatest measured value ofd 01 +0 0

33、.3 +0 0.35 +0 0.4 +0 0.45 +0 0.5 +0 0.6 +0 0.75 +0 0.9 +0 1.1 d 02 d 01machining allowance mm mm 25 to80 85 to100 105 to150 +0 0.5 +0 0.6 +0 0.8BS3821-3:1974 BSI 12-1999 5 4.3.2 Finish. All surfaces of the pellet bore shall be free from scratch marks and surface irregularities other than those natur

34、ally inherent in the finishing process. When assessed in accordance with BS1134 the roughness value shall be not greater than0.14m R a . 4.3.3 Concentricity. The external diameters of case and pellet shall be concentric with the bearing diameter within0.25mm total indicator reading up to and includi

35、ng150mm case diameter and0.5mm for sizes larger than150mm. 4.3.4 Squareness of back face. The back face shall be square relative to the axis of the bore within1 . 4.3.5 Tolerance on drawing angle. The drawing angle2! shall be accurate within 030. 4.4 Marking The finished dies shall be permanently an

36、d indelibly marked as specified in Part1 of this standard. Figure 3 Bar drawing dies for steel (reference letter C)BS3821-3:1974 6 BSI 12-1999 Table 4 Dimensions of bar drawing dies for steel Designation size Pellet Case d 2 h 2 d 1 s a l 4 b d 3 h 3 l 5 l 6 c min. max. min. min. max. min. max. min.

37、 max. mm mm mm mm mm mm mm mm mm mm mm mm mm mm 30/100 30 24 9 13 8.5 2.4 4.8 100 45 5 9 12 16 35/100 35 12 16 9.5 40/100 40 15 19 10.5 45/100 45 18 22 11.5 100 25 2.5 5.0 50 16 20 50/150 50 21 25 12.5 5 9 150 55/150 55 27 24 28 13.5 2.7 5.4 55 19 23 60/150 60 27 31 14.5 27 2.7 5.4 55 19 23 65/150 6

38、5 29 34 15.5 150 5 9 70/150 70 30 32 37 16.5 3.0 6.0 60 21 25 75/150 75 30 35 41 17.0 3.0 6.0 150 60 5 9 21 25 80/200 80 39 45 17.5 200 85/200 85 33 43 49 18.0 3.3 6.6 65 23 27 90/200 90 33 47 53 18.5 3.3 6.6 200 65 5 9 23 27 100/200 100 35 51 61 19.5 3.5 7.0 21 25 NOTE 1d 1 minis the minimum and pr

39、eferred diameter of bearing at the first application. NOTE 2d 1 maxis the maximum diameter of bearing which is recommended for drawing steel bars having a tensile strength up to900MPa in the drawn condition with a drawing angle2 up to and including20 . NOTE 3Dies for drawing steel bars with d 1maxex

40、ceeding61mm are outside the scope of this standard. NOTE 4The diameter of bearing d 1required by the user should be chosen within the limits d 1maxand d 1minexcept when the drawing angle2 exceeds20 . The tolerance of bearing should be specified by the user. NOTE 5For use on multiple draw benches a c

41、ase diameter d 3of125mm may be supplied for pellet diameters d 2of50mm,55mm and60mm and a case diameter d 3of175mm for pellet diameters d 2of80mm and85mm. a b l 4 =0.1h 2up to0.2h 2 c For information only.BS3821-3:1974 BSI 12-1999 7 Table 5 Dimensions of bar drawing dies for non-ferrous metal Figure

42、 4 Bar drawing dies for non-ferrous metal (reference letter D) Designation size Pellet Case d 2 h 2 d 1 s a l 4 b d 3 h 3 l 5 l 6 c min. max. min. min. max. min. max. min. max. mm mm mm mm mm mm mm mm mm mm mm mm mm mm 25/75 25 20 9 12 6.5 2.0 4.0 75 40 5 9 11 15 30/100 30 24 11 14 8.0 2.4 4.8 100 4

43、5 12 16 35/100 35 13 18 8.5 40/100 40 24 17 21 9.5 2.4 4.8 100 45 12 16 45/100 45 25 20 25 10.0 2.5 5.0 50 5 9 16 20 50/150 50 24 28 11.0 150 55/150 55 27 27 32 11.5 2.7 5.4 150 55 5 9 19 23 60/150 60 30 36 12.0 65/150 65 34 40 12.5 70/150 70 30 38 44 13.0 3.0 6.0 150 60 5 9 21 25 75/150 75 42 48 13

44、.5 80/200 80 46 52 14.0 200 85/200 85 33 50 56 14.5 3.3 6.6 200 65 5 9 23 27 90/200 90 54 60 15.0 95/200 95 58 64 15.5 100/200 100 35 62 68 16.0 3.5 7.0 200 65 5 9 21 25 105/250 105 65 72 16.5 250 NOTE 1d 1minis the minimum and preferred diameter of bearing at the first application. NOTE 2d 1maxis t

45、he maximum diameter of bearing which is recommended for drawing non-ferrous metal bars having a tensile strength up to800MPa in the drawn condition with a drawing angle2 up to and including25 . NOTE 3Dies for drawing non-ferrous metal bars with d 1maxexceeding72mm are outside the scope of this stand

46、ard. NOTE 4The diameter of bearing d 1required by the user should be chosen within the limits d 1maxand d 1minexcept when the drawing angle2 exceeds25 . If the drawing angle is considerably smaller than25 , the dimension d 1maxcan be increased by up to1mm. The tolerance of bearing should be specifie

47、d by the user. NOTE 5For use on multiple draw benches a case diameter d 3of125mm may be supplied for pellet diameters d 2of50mm and55mm and a case diameter d 3of175mm for pellet diameter d 2of80mm. a b l 4 =0.1h 2up to0.2h 2 c For information only.BS3821-3:1974 8 BSI 12-1999 Appendix A Information t

48、o be supplied when ordering Information to be supplied when ordering hardmetal as-sintered pellets and hardmetal dies for drawing round bar shall be in accordance with the designation system specified in Part1 of this standard. The following information shall also be given when ordering hardmetal as

49、-sintered pellets. 1) The outside diameter, d 02 . 2) The diameter of bearing, d 01 .BS3821-3:1974 BSI 12-1999 Publications referred to This standard makes reference to the following BritishStandards: BS970, Wrought steels in the form of blooms, billets, bars and forgings. BS970-1, Carbon and carbon manganese steels, including free cutting steels. BS1134, Method for the assessment of surface texture. BS4276, Hard metal for wire, bar and tube drawing dies. BS3821-3: 1974 BS

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