1、BRITISH STANDARD BS EN 10243-1:1999 Corrigendum No. 1 Steel die forgings Tolerances on dimensions Part 1: Drop and vertical press forgings The European Standard EN 10243-1:1999 has the status of a British Standard ICS 77.140.85 Incorporating EN 10243-1:1999This British Standard was published under t
2、he authority of the Standards Policy and Strategy Committee on 15 December 1999 BSI 14 February 2006 ISBN 0 580 35152 1 National foreword This British Standard is the English language version of EN 10243-1:1999, incorporating Corrigendum March 2005. Together with BS EN 10243-2, it supersedes BS 4114
3、:1967 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee ISE/31, Wrought steels, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards wh
4、ich implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This public
5、ation does not purport to include all the necessary provisions of a contract. Users are responsible for its 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,
6、 the EN title page, pages 2 to 34, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpreta
7、tion, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. Amendments issued since publication Amd. No. Date Comments 15703 14 February 2006 Correction to Table 6C E N European Committee for Standardization Co
8、mite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 3 6 , B-1050 Brussels 1999 CEN All rights of exploitation in any form and by any means reserved worldwide to CEN national Members. Ref. No. EN 10243-1:1999 E E U R O P E A N S T A N D A R D E N 1
9、0 2 4 3 - 1 N O R M E E U R O P E E N N E E U R O P A I S C H E N O R M S e p t e m b er 1 9 99 ICS 77.140.85 Incorporating Corrigendum March 2005 E n g l i sh v e r s i on S t e e l d i e f o r g i n g s T o l e r a n c e s o n d i m e n s i o n s P a r t 1 : D r o p a n d v e r t i c a l p r e s s
10、 f o r g i n g s P ie c es f o r ge es p ar e s t a m p a ge en a c i er T o le r a n c es d i m e n s i o n n e l l es P a r t ie 1: P ie c es e xe c u te es a c h a ud s ur m a r t e a u x - p i l o ns ou p r e s s es v e r t i c a l es G e s e n k s c h m i e d e t e i le a us S t a hl M a t o l
11、e r a n z en T e il 1: W a rm h e r g e s t e l lt in Ha m m e rn u nd S e n k r e c h t - P r e s s en This European Standard was approved by CEN on 22 August 1999. CEN members are bound to comply with the CEN/CENELEC Internal R e g u l a t i o n s which stipulate the conditions for giving this Eur
12、opean Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (Englis
13、h, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republ
14、ic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.EN 10243-1:1999 2 BSI 12 January 2006 Foreword This European Standard has been prepared by Technical Committee ECISS/TC 28, Steel forgings,
15、 the Secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by March 2000, and conflicting national standards shall be withdrawn at the latest by March 2000. This Europe
16、an Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. This European Standard is considered to be a supporting standard to those application and product standards which in themselves support an essential safety requirement of a
17、New Approach Directive and which make reference to this European Standard. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Ger
18、many, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.EN 10243-1:1999 BSI 12 January 2006 3 ContentsPage Foreword 2 1S c o p e 5 2 Normative references 5 3S y m b o l s 5 4 Information required in determining tolerances 6
19、4.1 Mass of forging 6 4.2 Shape of die line 6 4.3 Category of steel used 7 4.4 Shape complexity factor 7 4.5 Types of dimension 9 5 Categories of tolerances 9 5.1 Scope of categories 9 5.2 Definition of categories 10 5.3 Deviations of form 18 6 Use of tables 19 6.1 Tables 1 and 2 Tolerances for leng
20、th, width and height, residual flash (and trimmed flat), and mismatch 19 6.2 Table 3 and Table 4 Tolerances for thickness and ejector marks 20 6.3 Table 5 Tolerances for straightness, flatness and tolerances for centre-to-centre dimensions 20 6.4 Table 6 Tolerances for fillet and edge radii; toleran
21、ces for burrs; tolerances for sheared ends 21 7 Design procedure 21 7.1 Information required by the forger 21 7.2 Preparation of forging drawing 21 7.3 Indication of dimensions on forging drawing 21 7.4 Indication of tolerances on forgoing drawings 21 7.5 Importance of forging drawing 21 Annex A (in
22、formative) Examples of application 27 Figure 1 Die lines 6 Figure 2 Enveloping shapes of circular forgings 7 Figure 3 Enveloping shapes of non-circular forgings 8 Figure 4 Exception in determining shape complexity factor 8 Figure 5 Relationship between types of dimensions and die line 9 Figure 6 Typ
23、e of dimensions 10 Figure 7 Length and width dimensions between external surfaces 11 Figure 8 Length and width dimensions between internal surfaces 11 Figure 9 Length and width dimensions from a centre to a surface 12 Figure 10 Mismatch 13 Figure 11 Residual flash 13 Figure 12 Trimmed flat 13 Figure
24、 13 Application of thickness tolerances to deep hubs 14 Figure 14 Application of straightness tolerances 15 Figure 15 Dimensions to which centre-to-centre tolerances are applicable 15 Figure 16 Dimensions to which centre-to-centre tolerances are not applicable (other than by negotiation) 16 Figure 1
25、7 Fillet and edge radii 16EN 10243-1:1999 4 BSI 12 January 2006 Figure 18 Eccentricity tolerance for deep holes 17 Figure 19 Tolerances for unforged stock and sheared ends 18 Figure 20 Use of tables 20 Table 1 Drop and press forgings Forging grade F Tolerances for length, width, height, mismatch, re
26、sidual flash and trimmed flash 22 Table 2 Drop and press forgings Forging grade E Tolerances for length, width and height 23 Table 3 Drop and press forgings Forging grade F Tolerances for thickness and ejector marks 24 Table 4 Drop and press forgings Forging grade E Tolerances for thickness and ejec
27、tor marks 25 Table 5 Drop and press forgings Tolerances for straightness, flatness and centre-to-centre dimensions 26 Table 6 Drop and press forgings Tolerances for fillet, edge radii, burrs and sheared ends 26EN 10243-1:1999 BSI 12 January 2006 5 1 Scope 1.1 This European Standard specifies the dim
28、ensional tolerances for steel drop and vertical press forgings made under hammers and presses. The first part of this European Standard applies to hot forgings in the delivery condition, made in carbon and alloy steels. The tolerances specified apply to forgings not exceeding 250 kg in mass or 2 500
29、 mm maximum dimension. Tolerances for heavier or larger forgings shall be agreed at the time of enquiry and order. This European Standard does not apply to upset forgings made on horizontal forging machines (see EN 10243-2). 1.2 The tolerances shown in this European Standard cover both forgings to n
30、ormal requirements and forgings to a closer range of tolerances. These two grades of tolerances are identified as follows: forging grade F with tolerances providing an adequate standard of accuracy for the majority of applications and capable of being complied with by commonly used forging equipment
31、 and production methods; forging grade E providing closer tolerances to assist in acommodating those instances in which the normal manufacturing standards are inadequate. While grade E (close) tolerances may be applied to all dimensions on one forging, it is more economical to apply them only to tho
32、se specific dimensions on which closer tolerances are essential. This grade should not be specified unless the additional forging cost entailed can be justified by a consequent saving in overall cost. The tables showing dimensional tolerances are based on the R20 series of preferred numbers (see ISO
33、 3). Annex A gives for information some examples of the application of these tolerances for different types of closed die forgings. 1.3 Any occasional instances may necessitate the use of tolerances wider than those indicated, e.g. specially complicated designs and steels having particularly difficu
34、lt forging characteristics. In such cases these standard tolerances can form only a basis on which to agree modifications appropriate to the particular circumstances. 1.4 This European Standard does not include ranges of special tolerances closer than grade E. Such requirements usually necessitate s
35、upplementary operations, e.g. hot or cold coining or special processes such as warm or cold forging. Considerations of this nature, whilst frequently encountered, are highly individual, and vary widely. They are best dealt with by consultation at the design stage and shall be agreed between the purc
36、haser and the supplier. This approach will ensure that optimum use is made of the forging process in fulfilling the purchasers special requirements at the lowest additional cost. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publicati
37、ons. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. F
38、or undated references the latest edition of the publication referred to applies. ISO 3, Preferred numbers Series of preferred numbers. ISO 8015, Technical drawings Fundamental tolerancing principle. 3 Symbols The symbols used in this European Standard are as follows: l = length dimension; b = width
39、dimension; h = height dimension;EN 10243-1:1999 6 BSI 12 January 2006 4 Information required in determining tolerances To determine the tolerances applicable to a given forging in accordance with Table 1, Table 2, Table 3, Table 4, Table 5 and Table 6, the following information is required in additi
40、on to the dimensions of the forging: mass of forging; shape of die line; category of steel used; shape complexity factor; type of dimension. 4.1 Mass of forging The forging mass is calculated. 4.2 Shape of die line The shape of die line is determined as being within one of the following categories:
41、either straight or symmetrically cranked; or asymmetrically cranked (see Figure 1 for example). a = thickness dimension; d = diameter; r = radius; p = step dimension; u = height of burr; v = width of burr; t = theoretical length; e = special thickness across die line; m = mass (weight); = circle fac
42、tor; = density; S = shape complexity factor (see 4.4); M = category of steel (see 4.3); x and y = shearing deformation. Figure 1 Die lines EN 10243-1:1999 BSI 12 January 2006 7 4.3 Category of steel used The type of steel symbol used takes account of the fact that steels of high carbon and high allo
43、y content are more difficult to deform and cause higher die wear than do steels with lower carbon content and lower alloying elements. The category of steel used is determined as being within one of the following: group M1: Steel with carbon content not more than 0,65 % and total of specified alloyi
44、ng elements (Mn, Ni, Cr, Mo, V, W) not more than 5 % by mass; group M2: Steel with carbon content above 0,65 % or total of specified alloying elements (Mn, Ni, Cr, Mo, V, W) above 5 % by mass. To determine the category in which a steel belongs, the maximum permitted content of the elements in the st
45、eel specification shall be the values used. 4.4 Shape complexity factor The shape complexity factor takes account of the fact that in forging thin sections and branched components, as compared to components having simple compact shapes, larger dimensional variations occur which are attributable to d
46、ifferent rates of shrinkage, higher shaping forces and higher rates of die wear. Examples are shown of circular and non-circular forgings (see Figure 2 and Figure 3). The shape complexity factor of a forging is the ratio of the mass of the forging to the mass 1)of the enveloping shape necessary to a
47、ccommodate the maximum dimensions of the forging: The enveloping shape of a circular forging is the circumscribing cylinder, the mass of which is calculated from the formula (see Figure 2): where For a non-circular forging the enveloping shape is constituted by the smallest rectangular block that wi
48、ll encompass the forging (see Figure 3): m enveloping shape= lbhp 1) If desired, the shape complexity factor may be calculated as the ratio of the volume of the forging to the volume of the enveloping shape. d = diameter; = density (7,85 g/cm 3 ); h = height or length of cylinder. Figure 2 Enveloping shapes of circular forgings S m forging m enveloping shape - = m enveloping shape d 2 4 - h =EN 10243-1:1999 8 BSI 12 January 2006 The resulting shape complexity
