1、BRITISH STANDARDBS EN 15520:2007Thermal spraying Recommendations for constructional design of components with thermally sprayed coatingsThe European Standard EN 15520:2007 has the status of a British StandardICS 25.220.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g4
2、4g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 15520:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 September 2007 BSI 2007ISBN 978 0 580 57043 8National
3、forewordThis British Standard is the UK implementation of EN 15520:2007.The UK participation in its preparation was entrusted to Technical Committee STI/40, Thermally sprayed inorganic finishes.A list of organizations represented on this committee can be obtained on request to its secretary.This pub
4、lication 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 issued since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENN
5、EEUROPISCHE NORMEN 15520August 2007ICS 25.220.20English VersionThermal spraying - Recommendations for constructional designof components with thermally sprayed coatingsProjection thermique - Recommandations sur la conceptiondes assemblages dlments comportant un revtementdpos par projection thermique
6、Thermisches Spritzen - Empfehlungen zum konstruktivenGestalten von Bauteilen mit thermisch gespritztenSchichtenThis European Standard was approved by CEN on 20 July 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanS
7、tandard 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 member.This European Standard exists in three official versions (English, Fren
8、ch, 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 members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Cz
9、ech 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 and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPE
10、N DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15520:2007: EEN 15520:2007 (E) 2 Contents Page Foreword3 Introduction .4 1 Sc
11、ope 5 2 Normative references 5 3 Applications and specific properties of thermally sprayed coatings 5 4 Basic rules for design of components with thermal sprayed coatings .6 5 Design of components for partial coating by thermal spraying and final machining7 6 Machining and post-treatment of thermal
12、sprayed coatings 7 7 Instructions for design - Symbolic representation of the sprayed coating on drawings - Test instructions in the parts list .8 8 Examples for design suitable for spraying .8 Bibliography 18 Figures Figure 1 Thermal spraying of plane surfaces 10 Figure 2 Design of rotational symme
13、trical parts (thermal spraying of external surfaces). 11 Figure 3 Design of rotationally symmetrical parts (thermal spraying of internal surfaces) . 12 Figure 4a) Partial coating of an internal surface standard spray gun . 13 Figure 4b) Complete coating of an internal surface with special internal s
14、pray gun 13 Figure 5a) Coating pulled continued around chamfered edge 13 Figure 5b) Coating pulled continued around rounded edge . 13 Figure 6 Examples of design for parts avoiding excessive edge pressure. 14 Figure 7 Example of a lift piston, parent metal: Steel EN 10088-3-1.4571 Designation of coa
15、ting according to EN 14665 15 Figure 8 Example of a pump shaft, parent metal: Steel EN 10083-1 - C35+N. 16 Tables Table 1 Process related features and specific properties of thermal sprayed coatings . 6 Table 2 Basic rules and arguments. 7 Table 3 Customary minimum dimensions for internal spraying 9
16、 Table 4 Example of a parts list for finished pump shaft (see Figure 8b).17 EN 15520:2007 (E) 3 Foreword This document (EN 15520:2007) has been prepared by Technical Committee CEN/TC 240 “Thermal spraying and thermally sprayed coatings”, the secretariat of which is held by DIN. This European Standar
17、d shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2008, and conflicting national standards shall be withdrawn at the latest by February 2008. Attention is drawn to the possibility that some of the elements of t
18、his document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European St
19、andard: 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 and the United Kingdo
20、m. EN 15520:2007 (E) 4 Introduction Thermal spraying is applied to improve the surface properties of work pieces in order to increase the wear resistance, the electrical conductivity or the electrical resistance, to achieve corrosion resistance for the pertinent service conditions, to improve slidin
21、g behaviour or, to provide heat insulation. Recommendations for thermal spraying are contained in EN 14616. EN 15520:2007 (E) 5 1 Scope This European Standard applies for thermal sprayed coatings. It contains basic recommendations for the design of components, which have to be completely or partiall
22、y coated. The recommendations apply for new manufacturing as well as for repair of worn components. The coating may be of metallic, metal-ceramic, oxide-ceramic materials or polymers. 2 Normative references The following referenced documents are indispensable for the application of this document. Fo
23、r dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 14665, Thermal spraying Thermally sprayed coatings Symbolic representation on drawings 3 Applications and specific properties of thermally
24、sprayed coatings Due to their structure, thermal sprayed coatings possess properties which markedly distinguish them from bulk materials. An appropriate basic structural design and a suitable parent metal have to bear any mechanical loading. Usually, thermal sprayed coatings do not increase the stre
25、ngth of the parent work piece. Some process related features and specific properties of thermal sprayed coatings are summarised in Table 1. EN 15520:2007 (E) 6 Table 1 Process related features and specific properties of thermal sprayed coatings Process related features Specific properties of thermal
26、 sprayed coating Components made of almost every material can be coated by thermal spraying. Not every spraying procedure is appropriate for all applications. Coatings with properties completely different from the parent material are possible. Coatings can be sprayed with different spraying material
27、s side by side, one upon another, or mixing into one another (graded coatings). Usually the effect of the residual stress in the coating rises with increasing coating thickness. Usually the heat input caused by spraying is so low, that it is possible to avoid structural transformation or deformation
28、. The heat input by fusing self-fluxing alloys or diffusion annealing may cause structural transformation or deformation. If the coating is not post heat treated the bond strength mainly depends on mechanical adhesive properties. If the coating is post heat treated the bond strength depends on diffu
29、sion and the coating is densified. The ability to apply the spraying process is practically independent of the size of the component. Some geometric dimensions e.g. internal bores with too small a diameter may limit the spray ability. Components with complicated shapes can be coated, if appropriate
30、spraying equipment is used. Sprayed coatings are susceptible to edge loading, point and line loading and impact stresses. Areas of a component, which shall be free of sprayed material can be protected, e. g. by masking. The untreated surface of the coating provides a good basis for painting or seali
31、ng. Several thermal spraying processes can be applied on site as well as in a workshop. Coating properties e.g. porosity can be varied to suit particular applications. Sprayed coatings are micro porous except for post heat treated self-fluxing alloy coatings. 4 Basic rules for design of components w
32、ith thermal sprayed coatings Without proper consideration of the constructional design for thermal sprayed coatings, it may not be possible to achieve the desired properties of the coating. Designs which are suitable for thermal spraying will be suitable for pre-treatment, blasting and visual inspec
33、tion. Further design instructions for specific applications are contained in EN ISO 14921 and EN ISO 17834 and for the protection of steel structures against corrosion in EN ISO 12944-3, EN ISO 14713 and EN ISO 2063, which deal with the evaluation of coating material, processing and testing and give
34、 recommendations for coating thicknesses for several corrosive conditions. The most important rules for the design are summarised in Table 2. EN 15520:2007 (E) 7 Table 2 Basic rules and arguments Basic rules Arguments Explanations Sufficient accessibility of the area to be coated. The procedure, spr
35、ay gun with its electrical and/or gas connections, required spray distance and spray angle shall all be considered. Area to be coated shall be visible and attainable. Visible and within reach for the spray jet or tool moved by an operator or a manipulator. Sharp edges are to be avoided. Usually they
36、 cannot be coated, with a sufficient and uniform coating thickness. Coatings may be damaged on sharp edges. Sharp edges on holes and along cut edges shall be chamfered or rounded. Small internal radii are to be avoided. Turbulence of the spray jet, unfavourable angles of incidence, and irregular reb
37、ounding spray particles will occur which will lead to insufficient bond strength and density. Sprayed coatings in narrow holes, slots or in blind holes are to be avoided. Turbulence and spray particles which are insufficiently adherent to the wall may occur. Dust inclusions when coating internal sur
38、faces shall be minimised, see Figure 4. Special care to remove dust and heat. The spray jet should hit the surface at right-angles. The angle of incidence shall not be less than 45. Insufficient spray angles impair bond strength, efficiency, and coating structure. See Figures 4a) and 4b). The risk o
39、f spalling of the coating has to be minimised. The coating shall be continued around rounded or chamfered edges. See Figures 5a) and 5b). The risk of damaging the coating has to be minimised. A support edge or pocket (e. g. per Figure 8 detail X) may be employed. Welds to be coated shall be free of
40、splatters, undercuts and pores. Smoothing of such irregularities shall be required. Heat affected zone from thermally cut edges has to be minimised. Remove the hardened sharp edge of the cut. 5 Design for preparation of components and work pieces for thermal spraying When components or work pieces s
41、hall be only partially coated, the final machining to finished size of the whole component shall be carried out after spraying the coating. When manufacturing rotationally symmetrical components the blank should be pre-machined only in the area to be sprayed to the diameter appropriate for the coati
42、ng thickness. One example is shown in Figure 7. In case of thermal spraying of finish-machined parts or repair of parts by coating, areas which shall not be coated may be protected by appropriate measures (e. g. masking) for blasting and thermal spraying. 6 Machining and post-treatment of thermal sp
43、rayed coatings The different properties of thermal sprayed coatings compared to bulk materials shall be considered in machining processes. Procedures for machining, thermal post-treatment, or sealing of sprayed coatings are indicated in EN ISO 14924 and in EN ISO 14920. Impairment of the parent meta
44、l by any thermal post-treatment shall be considered. For details see EN ISO 14920. EN 15520:2007 (E) 8 7 Instructions for design - Symbolic representation of the sprayed coating on drawings - Test instructions in the parts list The symbolic representation of a sprayed coating on a drawing shall be a
45、ccording to EN 14665. If the symbolic representation does not cover the requirements for the coating, the coating specification shall be indicated in the pertinent parts list or by a note on the drawing. The coating specification shall contain the type of coating, pre-treatments, test procedures, re
46、quired values for e.g. tensile adhesive strength, hardness, etc. relevant for this component, and if applicable, the spraying procedure and post treatments. An example is given in Clause 8 of this standard in Table 4 and Figure 8. Instructions that define tests and the scope of tests shall be indica
47、ted in the parts list. Tests on component and tests on accompanying test specimens have to be indicated separately, see Figure 8 and Table 4. If further tests like corrosion or wear tests are required, test procedures and required results have to be agreed between the contracting parties. It is reco
48、mmended to indicate the general supply conditions as per EN 15311 in the pertinent parts list to specify requirements concerning quality management of the manufacturer and specific instructions for manufacturing and testing. 8 Examples for design suitable for spraying 8.1 Plane surfaces Examples are
49、 shown in Figure 1. Further examples for coatings for protection against corrosion of welded structures are presented in EN ISO 12944-3. 8.2 Rotationally symmetrical parts Restrictions of geometrical dimensions exist when coating inner surfaces. Specific conditions of the spray procedure such as spray distance and the size of spray spot have to be considered. Customary minimum dimensions for thermal spraying are contained in Table 3 (see also Figures 2 and 3). The actual dimensions depend on the procedure, equipment, and spray
