1、BRITISH STANDARD BS2772-2: 1989 Colliery haulage and winding equipment Part2: Specification for wrought steel UDC 669.1413:622.67BS2772-2:1989 This British Standard, having been prepared under the directionof the Iron and SteelStandards Policy Committee, was published underthe authority of the Board
2、ofBSI and comesintoeffecton 29September1989 BSI11-1999 First published September1956 First revision December1977 Second revision September1989 The following BSI references relate to the work on this standard: Committee reference ISM/31 Draft for comment87/35666 DC ISBN 0 580 17095 0 Committees respo
3、nsible for this British Standard The preparation of this British Standard was entrusted by the Iron and Steel Standards Policy Committee (ISM/-) to Technical Committee ISM/31, upon which the following bodies were represented: British Chain Manufacturers Association British Coal Corporation British F
4、orging Industry Association British Industrial Fasteners Federation British Steel Industry Cold Rolled Sections Association Department of Trade and Industry (National Physical Laboratory) Engineering Industries Association Federation of British Engineers Tool Manufacturers Institution of Production
5、Engineers Lloyds Register of Shipping Ministry of Defence National Association of Steel Stockholders Road Vehicle Spring Society Society of Motor Manufacturers and Traders Limited Stainless Steel Fabricators Association of Great Britain Amendments issued since publication Amd. No. Date of issue Comm
6、entsBS2772-2:1989 BSI 11-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Definitions 1 3 Steelmaking process 1 4 Chemical analysis 1 5 Freedom from defects 1 6 Sizes and tolerances 1 7 Condition of material on delivery 1 8 Grain size 1 9 Mechanical properties 1
7、 10 Manufacturers statement 2 Appendix A Methods of test for mechanical properties 3 Appendix B Information to be supplied by the purchaser 4 Appendix C Guidance on the selection of steels 4 Figure 1 Test block dimensions and ruling sections 6 Table 1 Restrictions on ladle analysis 1 Table 2 Mechani
8、cal properties 2 Publications referred to Inside back coverBS2772-2:1989 ii BSI 11-1999 Foreword This revision of this Part of BS2772 was prepared under the direction of the Iron and Steel Standards Policy Committee. It supersedes BS2772-2:1977 which is withdrawn. Major changes have been introduced
9、into this standard. In order to allow greater freedom in the selection of steels, chemical analysis requirements are no longer specified and steel selection is based on mechanical property requirements. Five groups of steel materials are specified, based on ascending levels of tensile strength. An a
10、ppendix to provide guidance on chemical composition for each of the five groups is included. Requirements for steel plates have been introduced for the first time. It should be noted that the specified mechanical properties relate to limiting ruling section and that for plate material where the prop
11、erties are obtained on quenched and tempered test pieces, this will be greater than the actual plate thickness. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a Briti
12、sh 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 to6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incor
13、porated. This will be indicated in the amendment table on the inside front cover.BS2772-2:1989 BSI 11-1999 1 1 Scope This Part of BS2772 specifies requirements for wrought steel plates, blooms, billets, slabs, bars, forgings and drop forgings to be used for colliery cage suspension gear, colliery tu
14、bs, mine-car drawgear and couplings and rope sockets. Details of information to be supplied by the purchaser are given in Appendix B. Appendix C gives guidance on chemical composition for each of the five groups of steels considered. NOTEThe titles of the British Standards referred to in this standa
15、rd are listed on the inside back cover. 2 Definitions For the purposes of this Part of BS2772 the following definitions apply. 2.1 limiting ruling section the largest diameter in which certain specified mechanical properties are achieved after a specified heat treatment for a particular composition
16、of steel 2.2 equivalent diameter the equivalent diameter of any product, or part of a product, is the diameter at the time of heat treatment of a hypothetical very long bar effectively of infinite length of uniform circular cross section which, if subjected to the same cooling conditions as the prod
17、uct, i.e.same initial and final temperature and same cooling medium, would have a cooling rate at its axis equivalent to that at the slowest cooling position in the product or relevant part 2.3 test sample that portion of the material selected for testing 2.4 test bar the test sample after preparati
18、on for heat treatment 2.5 test piece the test sample or test bar as finally prepared for mechanical testing 3 Steelmaking process Any steelmaking practice except the air or mixed air/oxygen bottom blown basic converter process shall be used. The steel shall be fully killed and made to a fine-grained
19、 practice. 4 Chemical analysis The ladle analysis of the steel shall be subject to the restrictions given in Table 1. Boron shall not be deliberately added to the steel. The minimum ratio of aluminium to nitrogen shall be2 : 1. NOTEAppendix C gives guidance on the selection of steels. Table 1 Restri
20、ctions on ladle analysis 5 Freedom from defects The material shall be free from pipe, segregation, cracks, laminations or surface flaws. Defects shall not be repaired by welding. NOTE 1In practice, the material needs to be free from such defects as might preclude its use for its intended purpose. NO
21、TE 2BS6512 gives guidance on surface discontinuities for plate material. 6 Sizes and tolerances 6.1 Sizes and tolerances of plate shall comply with BS4360. 6.2 Sizes and tolerances of blooms, billets, slabs and bars shall comply with BS970-1. 6.3 Sizes and tolerances of drop and press forgings and u
22、pset forgings made on horizontal forging machines shall comply with BS4114. 7 Condition of material on delivery Plates, blooms, billets, slabs and bars shall be delivered “as rolled” or “as forged”. Forgings and drop forgings shall be delivered in the condition stated on the order. 8 Grain size In o
23、rder to demonstrate that a fine-grained steelmaking practice has been employed, the material shall exhibit either: a) a minimum of0.015% soluble aluminium content on ladle analysis; or b) a grain size of5 or finer which, in cases of dispute, shall be tested in accordance with Appendix A. 9 Mechanica
24、l properties The mechanical properties obtained from test pieces selected, prepared and tested in accordance with Appendix A shall meet the requirements given in Table 2. Phosphorus Sulphur Nitrogen (% max.) 0.04 0.04 0.012BS2772-2:1989 2 BSI 11-1999 For the Charpy V-notch impact test (seeA.3.2), th
25、e average value of the three tests shall meet the value given in Table 2. Not more than one individual value shall be lower than the value given in Table 2 and it shall be not lower than70% of that value. If retesting is necessary (seeA.3.2) the average value of the six tests shall meet the value gi
26、ven in Table 2. Not more than two of the individual values shall be lower than the value given in Table 2 and not more than one shall be lower than70% of that value. NOTEMechanical properties quoted in Table 2 are related to limiting ruling sections. Figure1 of Appendix A, derived from BS5046, shoul
27、d be used to determine the equivalent diameter and test bar size and hence the applicability of the properties quoted. 10 Manufacturers statement The manufacturer shall supply a certificate giving details of the ladle analysis of the material, the method of steelmaking and the results of the mechani
28、cal tests. Table 2 Mechanical properties Group of steel Product form Limiting ruling section Minimum values of mechanical properties Tensile strength R m Yield strength R e Elongation on5.65S o Minimum Charpy V-notch impact testvalues at20 C 1 Plate All other forms All forms All forms mm u 100 u 100
29、 100u 150 150 N/mm 2 490 540 490 430 N/mm 2 340 340 310 280 % 24 24 23 22 J 80 80 60 55 2 All forms All forms u 150 150 u 250 540 540 340 340 24 20 68 55 3 All forms All forms u 150 150 u 250 620 620 435 435 19 19 47 37 4 All forms u 63 770 540 17 40 5 All forms All forms 63 u 150 150 u 250 850 850
30、680 650 15 15 55 20BS2772-2:1989 BSI 11-1999 3 Appendix A Methods of test for mechanical properties A.1 Selection and preparation of samples A.1.1 Material not supplied in the finally heat-treated condition A.1.1.1 Blooms, billets, slabs, bars, forgings and drop forgings. Where the ruling section of
31、 the material does not differ appreciably from that of the forging or parts to be produced, test samples shall be taken either: a) directly from the material and heat treated in the original size; or b) where the results of heat treating in the original size would be obtained on the forgings or part
32、s to be produced, by forging and/or machining to test bars of a diameter equivalent to the ruling section of the forgings or parts at the time of heat treatment. Test bars shall be given the representative heat treatment for the parts concerned. One tensile test and three Charpy V-notch impact tests
33、 shall be made on any batch of material of similar ruling section from the same cast. For the purpose of subsequent orders, these tests shall be taken as representing all sizes of material from the same cast where the ruling section of the forgings or parts does not exceed the ruling section of the
34、test bar already tested. A.1.1.2 Plates. A test coupon shall be taken from a plate from each cast and water-quenched and tempered. The size and ruling section of this coupon shall be in accordance with Figure 1. If the plate tested is50mm thick or greater, this shall cover all thicknesses rolled fro
35、m that cast. If the plate tested is less than50mm thick, this shall cover plates from that cast up to50mm thick. If, subsequently, plates thicker than50mm are produced from that cast, then a further coupon shall be taken from a plate50mm or thicker and quenched and tempered. One tensile test and thr
36、ee Charpy V-notch impact tests shall be made on each test coupon. A.1.2 Bars for machining as supplied in the finally heat-treated condition The samples shall be cut from the heat-treated bars and shall not be subject to further heat treatment nor, except for that required to prepare the test piece,
37、 to further mechanical working. One tensile test and three Charpy V-notch impact tests shall be made on each batch of bars of similar size which have originated from the same cast and have been heat treated together. A.1.3 Forgings, drop forgings and machined parts Samples for mechanical testing sha
38、ll be taken by one of the following methods. a) For forgings and drop forgings with a ruling section equivalent to a diameter greater than29mm, a prolongation shall be provided on a representative proportion of the forgings or drop forgings. The prolongation shall have a diameter equal to the ruling
39、 section of the forging or drop forging at the time of heat treatment and shall not be finally severed until after heat treatment. b) Where integral test pieces are not practicable, for forgings and drop forgings with ruling sections equivalent to a diameter of29mm or less and for parts machined fro
40、m bars not finally heat treated, separate test pieces shall be provided. These shall be provided from the bars or billets from which the forgings, drop forgings or parts are made, or from additional forgings, drop forgings or parts. The test samples shall be forged and/or machined to test bars of a
41、diameter equivalent to the ruling section of the forgings, drop forgings or parts and shall be heated with the material they represent. A.1.4 Samples for grain size test Where a grain size test is required (see clause8), one test sample for the determination of austenitic grain size shall be selecte
42、d for each cast. A.2 Location of tensile and Charpy V-notch impact test pieces Tensile test pieces shall be taken in the longitudinal or transverse direction. Charpy test pieces shall be taken longitudinally. For ruling sections up to and including25mm, the test piece shall be machined co-axially fr
43、om the heat-treated test bar. For ruling sections over25mm, the longitudinal axis of the test piece shall be12.5mm from the surface of the heat-treated test bar. A.3 Test methods A.3.1 Tensile test The tensile test shall be carried out in accordance with BS18. Tensile test pieces shall be machined f
44、rom plates, blooms, billets, slabs, bars, forgings and drop forgings to the dimensions of the largest, practical, round test piece, from those specified in BS18 that can be obtained having a gauge length equal to5.65S o . NOTEFor material not greater than50mm in diameter or width across flats, unmac
45、hined test pieces having a gauge length equal to5.65S omay be used.BS2772-2:1989 4 BSI 11-1999 If any of the original test results fail to meet the values specified in Table 2, twice the original number of test samples shall be selected for retesting. One of these shall be taken from the plate, bloo
46、m, billet, slab, bar, forging or drop forging from which the original test sample was taken unless that item has been withdrawn by the manufacturer. In the case of material supplied in the heat-treated condition, the manufacturer shall have the right to re-heat treat the material and to resubmit it
47、for testing. If any of the retests fail, the material represented shall be deemed not to comply with this Part of this British Standard. A.3.2 Charpy V-notch impact test The Charpy V-notch impact test shall be carried out in accordance with BS131-2 at a temperature of20 C. The individual results of
48、the three tests shall be recorded and the average value calculated. If the average of the original three impact values is lower than the value specified in Table 2, or if any one value is lower than70% of that value, three additional test pieces shall be taken from the sample and tested. With materi
49、al supplied in the heat-treated condition, the manufacturer shall have the right to re-heat treat the material and resubmit it for testing. If the requirements of clause9 are not fulfilled, the material represented shall be deemed not to comply with this Part of BS2772. A.3.3 Grain size test When required (see clause8), a grain size test shall be carried out in accordance with the McQuaid Ehn method given in BS4490. If the test sample fails to meet the requirements specified in clause8 b), a second sample shall be tested. If this retest confirms the failu
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