1、BRITISH STANDARDBS EN ISO 14744-1:2008Welding Acceptance inspection of electron beam welding machines Part 1: Principles and acceptance conditionsICS 25.160.30g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g
2、55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 14744-1:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2008 BSI 2008ISBN 978 0 580 57187 9National forewordThis British Standard is the UK implementation of EN
3、ISO 14744-1:2008. It supersedes BS EN ISO 14744-1:2001 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee WEE/-/1, Briefing committee for welding.A list of organizations represented on this committee can be obtained on request to its secretary.This public
4、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 cannot confer immunity from legal obligations.Amendments/corrigenda issued since publicationDate CommentsEUROPEAN STANDARDNORME EUROPENNE
5、EUROPISCHE NORMEN ISO 14744-1May 2008ICS 25.160.30 Supersedes EN ISO 14744-1:2000 English VersionWelding - Acceptance inspection of electron beam weldingmachines - Part 1: Principles and acceptance conditions (ISO14744-1:2008)Soudage - Essais de rception des machines de soudagepar faisceau dlectrons
6、 - Partie 1: Principes et conditionsde rception (ISO 14744-1:2008)Schweien - Abnahmeprfung von Elektronenstrahl-Schweimaschinen - Teil 1: Grundlagen undAbnahmebedingungen (ISO 14744-1:2008)This European Standard was approved by CEN on 26 April 2008.CEN members are bound to comply with the CEN/CENELE
7、C Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN
8、 member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN memb
9、ers are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Sw
10、itzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. E
11、N ISO 14744-1:2008: EForeword This document (EN ISO 14744-1:2008) has been prepared by Technical Committee ISO/TC 44 “Welding and allied processes“ in collaboration with Technical Committee CEN/TC 121 “Welding” the secretariat of which is held by DIN. This European Standard shall be given the status
12、 of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2008, and conflicting national standards shall be withdrawn at the latest by November 2008. Attention is drawn to the possibility that some of the elements of this document may be the sub
13、ject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 14744-1:2000. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to impleme
14、nt this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland an
15、d the United Kingdom. Endorsement notice The text of ISO 14744-1:2008 has been approved by CEN as a EN ISO 14744-1:2008 without any modification. BS EN ISO 14744-1:2008ii blankiv Introduction Components, failure of which will endanger life, are subject to comprehensive test and acceptance specificat
16、ions, which, among other things, require production equipment to be of proven type and in accordance with the state of the art. Similarly, in welding practice, standards apply that specify, for example, the required manual skills which a welder must have for controlling the weld. In welding processe
17、s that are not under direct manual control, such as in electron beam welding, requirements for various machine parameters are established. This standard series on acceptance inspection of electron beam welding machines is based on the concept that the production of continuously high-quality welds is
18、 ensured if, among other things, the settings, within defined limits, are reproducible during the operating period. Taking this into account, this standard specifies details of the main machine parameters (accelerating voltage, beam current, lens current and welding speed characteristics) together w
19、ith deviations permitted in short-term or long-term operation. It also includes requirements regarding the run-out accuracy of the devices positioning the workpiece and regarding the stability of the spot position of the electron beam. Users, manufacturers, research experts and inspection bodies are
20、 all agreed that electron beam welding machines complying with the requirements are suitable for welding components subject to acceptance inspection, such as aircraft equipment, pressure vessels, valves, etc., within specified setting ranges, assuming that other conditions (e.g. qualified staff, qua
21、lity control) are fulfilled. ISO 14744 any part(s) can be referred to in contracts for supply of electron beam welding machines. Further tests are not normally required if proof of satisfactory welding results is provided in the form of routine inspection documentation. However, the requirements of
22、the standard can also be used for inspection as part of maintenance, if required by contract. BS EN ISO 14744-1:20081Welding Acceptance inspection of electron beam welding machines Part 1: Principles and acceptance conditions 1 Scope This part of ISO 14744 specifies requirements for acceptance inspe
23、ction of electron beam welding machines preferably when first installed on the users premises. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest ed
24、ition of the referenced document (including any amendments) applies. ISO 17662, Welding Calibration, verification and validation of equipment used for welding, including ancillary activities 3 Symbols and abbreviated terms For the purposes of this part of ISO 14744, the following symbols apply: AFfo
25、cal distance, in millimetres AWwork distance, in millimetres ax; ay; azdeviation, in millimetres, of electron beam axis from weld groove centre or of beam focus from groove centre on weld surface in the x-, y- or z-direction of feed, as a measure of the run-out accuracy D diameter, in millimetres or
26、 in centimetres, of a circumference weld seam IBbeam current, in milliamperes IB maxmaximum beam current, in milliamperes, corresponding to UA maxand UA min, respectively IB minminimum beam current, in milliamperes, corresponding to UA maxand UA min, respectively ILlens current, in milliamperes IL m
27、axlens current, in milliamperes, at UA maxand for AF minIL minlens current, in milliamperes, at UA minand for AF maxBS EN ISO 14744-1:20082 m load, in kilograms force, on the work table or on rotating fixture resulting from workpiece mass including that of any clamping device n rotational frequency,
28、 in reciprocal minutes, of rotating fixture twtime, in seconds, for welding a seam tw maxmaximum time, in seconds, for welding a seam Q pressure rise rate, in pascal cubic decimetres per second, or millibarlitres per second UAindicated accelerating voltage, in kilovolts UA maxmaximum indicated accel
29、erating voltage, in kilovolts, within the setting range UA minminimum indicated accelerating voltage, in kilovolts, within the setting range Uamonitored voltage for measuring the accelerating voltage, in millivolts Ubmonitored voltage, in millivolts, for measuring the beam current, in millivolts Uvm
30、onitored voltage, in millivolts, for measuring the welding speed v welding speed, in millimetres per second, in centimetres per minute or in metres per minute 4 Conditions for acceptance inspection 4.1 General Acceptance inspection shall be performed after the first installation or before the first
31、operation of the welding machine. The following tests shall be done: accelerating voltage characteristics; beam current characteristics; lens current characteristics; speed characteristics of movement devices; run-out accuracy of movement devices; stability of spot position. And the following test m
32、ay be agreed: pressure rise rate. After changing of equipment location the following test shall be done: speed characteristics of movement devices; run-out accuracy of movement devices; stability of spot position. BS EN ISO 14744-1:20083And the following test may be agreed: pressure rise rate. After
33、 rebuilding, maintenance or changing the conditions of operation the following tests shall be done: tests of all affected machine components. The acceptance inspection may be extended on parameters, characteristics and additional devices, when there are no requirements described in ISO 14744 (all pa
34、rts). In these cases, requirements and limit deviations shall be agreed. However, measurement of accelerating voltage may be performed prior to delivery of the welding machine in accordance with ISO 14744-2. 4.2 Installation of electron beam welding machine Electron beam welding machines shall be in
35、stalled so that acceptance inspection and machine performance are not interfered with by vibration or by electrical or magnetic fields. 4.3 Power source The power source for electron beam welding machines shall be an electrical mains system with voltage fluctuations not exceeding 10 %. 4.4 Safety pr
36、ecautions This part of ISO 14744 does not cover inspection of safety devices and other safety aspects. IMPORTANT Machines for electron beam welding have several features which assure safe operation. The electron beam generates x-rays during welding and the work chamber walls, the work chamber window
37、s and other parts have to reduce the radiation outside the machine to low safe levels so as to permit operators and other personnel to work safely close to the machine. The parts of the machine subject to high-voltages should, of course, be protected and inaccessible when under high tension. Some of
38、 the features which assure safe operation may have to be tested after installation of the machine, prior to any use of the machine in production. Any such test is, however, outside the scope of this part of ISO 14744. The tests have to be specified by the supplier of the machine. In addition, it is
39、important to consider that the design of machines for electron beam welding, protection against x-rays etc., are subject to several legal requirements at the European level (e.g. directives for: machines; electromagnetic compatibility; low-voltage equipment) and supplementary national requirements i
40、n at least some countries. See also IEC 60204-1. 4.5 Operating instructions The operating instructions for the electron beam welding machine shall be complied with. 4.6 Instruments The accuracy of all instruments for measurement shall be compatible with the limit deviations specified in this part of
41、 ISO 14744, see Table 1. In accordance with ISO 17662, no calibration, no verification, and no validation of measurement equipment is necessary. BS EN ISO 14744-1:20084 5 Principles of acceptance inspection 5.1 Setting range The setting range shall be specified for the machine to undergo the accepta
42、nce inspection, giving setting ranges for the following parameters: accelerating voltage; beam current; lens current; welding speed in all primary welding directions. Other parameters necessary for proper control of the welding machine shall also be specified, e.g.: focal distance; load resulting fr
43、om workpiece and fixture mass; pressure rise rate (if necessary). 5.2 Limit deviations for machine parameters and characteristics The limit deviations given in Table 1 relate to the mean of the measured values concerned, unless otherwise specified. The limit deviations relate to the use of electron
44、beam welding machines without special requirement. Alternative deviations may be agreed by contract for special machines or special applications. BS EN ISO 14744-1:20085Table 1 Limit deviations for machine parameters and characteristics Parameters and characteristics Limit deviations of the measured
45、 value Accelerating voltage: ripple stabilization reproducibility 2 % (peak-to-peak value) 1 % 1 % Beam current: ripple stabilization reproducibility 5 % (peak-to-peak value) 1 % 1 % Lens current: ripple stabilization reproducibility 0,5 % (peak-to-peak value) 0,5 % 0,5 % Welding speed: short-term s
46、tability long-term stability reproducibility 2 % 1 % 1 % Run-out accuracy, longitudinal and circumferential welds 0,1 mm Unless otherwise agreed, requirements may be relaxed for welding of large pieces Stability of spot position in the plane perpendicular to the beam axis 0,1 mm up to a focal distan
47、ce of 300 mm Stability of spot position for longer focal distance to be agreedPressure rise rate To be agreed (see Annex A) 5.3 Test report All inspection results shall be recorded in a test report which includes: reference to this part of ISO 14744; all measured results; assessment of all measureme
48、nt results; the name of the responsible welding supervisor; and description the setting range, which complies with the requirements of this part of ISO 14744. The test report has to be signed by the examiner. BS EN ISO 14744-1:20086 6 Acceptance inspection 6.1 General The acceptance inspection speci
49、fied below is applicable for general applications for electron beam welding machines. Alternative conditions may be agreed for special applications. However, the applicability of limit deviations specified in Table 1 has to be assessed for such special applications. 6.2 Accelerating voltage, beam current, and lens current 6.2.1 Measurement procedure ISO 14744-2 specifies details of the method of measurement, the test arrangement and the procedure to be followed in measuring the accelerating volta
