1、STDeBSI BS EN IS0 L4744-b-ENGL 2001 D Lb24bb9 0902898 717 = BS EN IS0 BRITISH STANDARD Welding - Acceptance inspection of electron beam welding machines - Part 6: Measurement of stability of spot position The European Standard EN IS0 1474442000 has the status of a Britkh Standard ICs 25.160.30 NO CO
2、PYING WITHOUT BSI PERMISSION EXCEPT AS PERMiITED BY COPYRIGHT LAW 14744-6:2001 STDmBSI BS EN IS0 L4744-b-ENGL 2001 = Lb24bb9 0702897 653 E BS EN IS0 14744-6:2001 Amd. No. This British Standard, having been prepared under the direction of the Engineering Sector Committee, was published under the auth
3、ority of the Standards Committee and comes into effect on 15 April 2001 Date Comments O BSI 04-2001 ISBN O 580 34195 X National foreword This British Standard is the official English language version of EN IS0 14744-6:2000. It is identical with IS0 14744-62000. The UK participation in its preparatio
4、n was entrusted to Technical Committee WEW47, Miscellaneous welding standards, which has the responsibility to: - aid enquirers to understand the text; - present to the responsible intemationavEuropean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests
5、informed; - monitor related intemational and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references Attention is drawn to the fact that CEN and CENELEC standards normally include an anne
6、x which lists nonnative references to international publications with their corresponding European publications. The British Standards which implement these intemational or European publications may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspon
7、dence Index“, or by using the “Find“ faciily of the BSI Standards Electronic Catalogue. 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 British Standard does not of i
8、tself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN IS0 titie page, pages 2 to 9 and a back cover. The BSI copynght notice displayed in this document indicates when the document was last issued. EUROPEAN STANDARD NORME E
9、UROPENNE EUROPISCHE NORM EN IS0 14744-6 April 2000 ICs 25.160.00 English version Welding - Acceptance inspection of electron beam welding machines - Part 6: Measurement of stability of spot position (IS0 14744-6:2000) Soudage - Essais de rception des machines de soudage par faisceau dlectrons - Part
10、ie 6: Mesure de la stabilit de la position de la tache focale (IS0 14744-6:2000) Schweien - Abnahmeprfung von Elektronenstrahl- Schweimaschinen - Teil 6: Messen der Flecklagekonstanz (IS0 14744-6:2000) This European Standard was approved by CEN on 3 January 2000. CEN members are bound to comply with
11、 the CENKENELEC Internal Regulations which stipulate the conditions for giving this European 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
12、 or to any CEN member. This European Standard exists in three official versions (English, 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 officiai ve
13、rsions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMTTEE FOR STANDARDIZATION EUROPISCHES K
14、OMITEE FUR NORMUNG COMITE EUROPEEN DE NORMALISATION Central Secretariat: rue de Stassart, 36 B-1050 Brussels O 2000 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN IS0 14744-6:2000 E Paae 2 EN-IS0 14744-6:2000 Contents Page Forewor
15、d . 3 1 Scope 4 2 Normative references . 4 3 Termsanddefinitions 4 4 Testarrangement 4 4.1 General . 4 4.2 Workpiece preparation . 5 5 Measurement procedure 5 5.1 Welding machine with optical viewing system . 5 5.2 Welding.machine without optical viewing system 8 6 Evaluation . 9 Foreword The text o
16、f EN IS0 14744-6:2000 has been prepared by Technical Committee CENTTC 121 “Welding“, the secretariat of which is held by DS, in collaboration with Technical Committee ISOTTC 44 “Welding and allied processes“. This European Standard shall be given the status of a national standard, either by publicat
17、ion of an identical text or by endorsement, at the latest by October 2000, and conflicting national standards shall be withdrawn at the latest by October 2000. According to the CENKENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement thi
18、s European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. This draft European Standard is composed of the six following parts: - Part 1: Prin
19、ciples and acceptance conditions; - Part 2: Measurement of accelerating voltage characteristics: - Part 3: Measurement of beam current characteristics; - Part 4: Measurement of welding speed; - Part 5: Measurement of run-out accuracy; - Part 6: Measurement of stability of spot position. STD*BSI BS E
20、N IS0 14744-b-ENGL 2001 3624667 0902903 904 Page 4 EN-IS0 14744-6:2000 1 Scope This standard is intended for use when the stability of spot stability of welding machines complying with EN IS0 14744-1 is to be measured in connection with an acceptance inspection. It provides essential information to
21、the procedure and apparatus to be used for making the measurements. The stability of the spot position is a particularly significant parameter for prolonged welding applications and for electron beam welding with automatic devices positioning the workpiece. In such applications, the welding machine
22、shall be able to reproduce, over prolonged periods and without additional correction of the position being required, a given beam-to-joint alignment. The purpose of measurement is to check whether and to what extent the electron beam generated by a welding machine keeps within the range of limit dev
23、iations specified for the spot position. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated refer
24、ences, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN IS0 14744-1:2000 Welding - Acce
25、ptance inspection of electron beam welding machines - Part 1: Principles and acceptance conditions (IS0 14744-1 : 2000) Welding - Acceptance inspection of electron beam welding machines - Part 3: Measurement of beam current EN IS0 14744-3 (IS0 14744-3 2000) IS0 1302 Technical drawings - Method of in
26、dicating surface texture 3 Terms and definitions For the purposes of this European Standard, the following term and definition applies, 3.1 Spot position geometrical position of the electron beam when it impinges on the workpiece surface (weld point) with respect to a system of coordinates perpendic
27、ular to the axis of the beam. 4 Test arrangement 4.1 General During the specified test period, the electron beam, at a given power, transmits its energy to a heatsink A or to a Faraday cup as described in EN IS0 14744-3 (see figure 1). For the actual measurement, a specially prepared workpiece, B, s
28、hall be positioned in the beam axis and the beam power adjusted to the welding task (small melt spots or melt runs). The beam focal distance employed shall be the maximum practical in the work chamber. The heatsink or the Faraday cup and the workpiece B shall be arranged relative to each other so as
29、 to prevent any thermal interaction. To determine the beam current required for the measurement, as is normal in welding practice, a third workpiece, C, of the same height as workpiece B shall be provided (see figure 1). To avoid beam deflection, the workpieces and devices used shall be made of non-
30、magnetizable materials. STD=BSI BS EN IS0 14744-b-ENGL 2001 W Lb24bb9 0902904 840 = EN IS0 14744-6:2000 5 %eatsink or Faraday cup 2 Screen (to prevent possible thermal interaction 3 Workpiece B wit coordinate axis, fixed to the work table 4 Workpiece C 5 Work table A Figure 1 - Test arrangement for
31、measuring the stability of spot position ?he T est ai ri angement 4.2 Workpiece preparation The surface of workpiece B intended to be measured shall have a roughness value, Ra, equal to 1,6 pm as specified in IS0 1302. 5 Measurement procedure 5.1 Welding machine with optical viewing system 5.1.1 Gen
32、eral The measurement shall be carried out with the welding machine set as specified in 6.5 of EN IS0 14744-1 :2000. No modifications, particularly no adjustments, shall be made to the welding machine between the steps described in the following subclauses. 5.1.2 Welding machine with a CNC work table
33、 Measurements shall be carried out in the following way: 1) before starting the measurements, the settings necessary to obtain a small melt spot shall be determined for the selected focal distance on workpiece C, see figure 1 ; 2) then the first spot P, shall be melted on workpiece B by programming
34、in the CNC-position: x, = 0,000 mm; y, = 0,000 mm; x, = 5,000 mm; y, = 0,000 mm; and x, = 0,000 mm; y, = 5,000 mm; see figure 2. 3) The next spots P, and P, shall be melted at the coordinates: STD-BSI BS EN IS0 L4744-b-ENGL ZU01 E 1624bb9 0902905 787 = Page 6 EN IS0 14744-6:2000 Figure 2 - Spot weld
35、s arrangement with CNC work table To avoid backlash it is important to move the work table only in the same X- or Y-direction to reach the (- U) positions. 4) heatsink A or Faraday cup shall be positioned in the beam axis. The welding machine shall be switched on, interrupted and be set and maintain
36、ed at the power and operating time specified in EN IS0 14744-1 :2000 in 6.5; 5) workpiece B shall be positioned with table coordinates: x, = 5,000 mm; y, = 5,000 mm; and the fourth spot shall be melted. 6) using the reference spots P, P, and P, workpiece B shall be positioned in the X- and Y-directi
37、on of a workshop travelling microscope. The coordinates x, and y; of the spot center P, shall be measured. The deviation from the correct position x, y, shall be calculated as follows: where Ax = x, - x, If a focal distance other than 300 mm has been used for melting the spots, the value Ar thus obt
38、ained shall be converted proportionally on Ar to A, = 300 mm. AY = Y, - Y4 5.1.3 Welding machine without a CNC work table 5.1.3.1 Workpiece B Using a marking tool and a set square rule, engrave a system of axes (Y, X, and X,) on the surface of workpiece B as shown in figure 3, in such a way that val
39、ues can be read to an accuracy of * 0,02 mm under a workshop travelling microscope. - Page 7 STD-BSI BS EN IS0 14744-b-ENGL 2001 m Lb24bb9 09029Ob hL3 D EN IS0 14744-6:2000 Figure 3 - Coordinate axes on workpiece B 5.1.3.2 Measurements Measurements shall be carried out in the following way: 1) befor
40、e starting the measurements, the settings necessary to obtain a small melt spot shall be determined for the selected focal distance on workpiece C, see figure 1. It shall be ensured by a slight adjustment that the melt spot is not at the centre of the coordinate system viewed through the viewing sys
41、tem; 2) then, workpiece 6, having the same focal distance as workpiece C, shall be positioned under the optical viewing system so that axes Y and X, coincide with axes Y and X of the viewing system (see figure 4). Following that, spot PA shall be melted, using the values previously determined (see f
42、igure 4); Figure 4 - Axes as seen through optical viewing system 3) heatsink A or the Faraday cup, as appropriate, shall be positioned on the beam axis. The welding machine shall be switched on, interrupted and be set and maintained at the power and operating time specified in 4) workpiece B shall b
43、e positioned under the optical viewing system so that axes Y and X, coincide with axes Y and X of the viewing system (see figure 5). Following that, spot P, shall be melted, using the same settings, see figure 5; EN IS0 14744-1; YIY Figure 5 - Melt spots as seen through optical viewing system STD-BS
44、I BS EN IS0 L4744-b-ENGL 2OOL I 1624667 0902907 55T H Page 8 EN IS0 14744-6:2000 5) using a workshop travelling microscope, distances x, and y, as well as x, and y, of weld spots PA and P, shall be measured, see figure 6. The stability of the spot positions shall be calculated from distances x, and
45、x, for the X-axis and distances y, and y, for the Y-axis. where Ax = x, - x2 If a focal distance other than 300 mm has been used for melting the spots, the value Ar thus obtained shall be converted proportionally on Ar to A, = 300 mm. AY = Y, - Y2 Figure 6 - Melt spots on workpiece B 5.2 Welding mac
46、hine without optical viewing system 5.2.1 General Only general information on the measurement procedure can be given, since the procedure depends, to a large extent, on the structure and the mode of operation of the welding machine. 5.2.2 Initial and end positions of focal spot Instead of melting sp
47、ots, before and after continuous operation of the machine, concentric circular melt runs shall be made on workpiece B by moving the beam around in a circular path, see figure 7. Run RA shall be made prior to, and run R, after continuous operation, the radius of the latter being changed so that in th
48、e event of a displacement of the focal spot, the two runs will not overlap and thus prevent correct measurement. The machine settings for the runs shall be determined separately using a third workpiece, C, whilst the welding parameters for continuous operation are specified in EN IS0 14744-1. For th
49、is purpose, it is assumed that the welding machine is equipped with devices permitting automatic positioning of the workpiece in relation to the beam axis without an optical viewing system being required. The positioning accuracy of these devices shall, where necessary, be tested separately. RA t I Figure 7 - Workpiece B with circular melt runs STDmBSI BS EN IS0 14744-b-ENGL 2001 = 1b24bb9 0902908 496 Page 9 EN IS0 14744-612000 5.2.3 Measuring the stability of spot position Distances x, s, y, and y, on the four coordinate axes shall be measured using a
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