1、BRITISH STANDARD AEROSPACE SERIESBS 2X 34:1998Incorporating Amendment No. 1Specification for two component polyurethane finish for aerospace purposesICS 49.040g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g
2、55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS 2X 34:1998This British Standard, having been prepared under the direction of the Engineering Sector Board, was published under the authority of the Standards Board and comes into effect on 15 April 1998 BSI 16 November 2005First published
3、 1 May 1992The following BSI references relate to the work on this standard:Committee reference ACE/44Draft for comment 96/705060 DCISBN 0 580 27986 3Committees responsible for this British StandardThe preparation of this British Standard was entrusted to Technical Committee ACE/44, Protective treat
4、ments and aircraft finishes, upon which the following bodies were represented:British Coatings Federation Ltd.Metal Finishing AssociationMinistry of DefenceNational Centre of TribologyOil and Colour Chemists AssociationSociety of British Aerospace CompaniesAmendments issued since publicationAmd. No.
5、 Date Comments15985 16 November 2005 See ForewordBS 2X 34:1998 BSI 16 November 2005iContentsPageCommittees responsible Inside front coverForeword ii1Scope 12 Normative references 13 Definitions 14 Materials 15 Performance 16Batch inspection 27 Marking 4Annex A (normative) Type approval 5Annex B (nor
6、mative) Preparation of test panels 5List of references 6Table 1 Tests on liquid paint 2Table 2 Tests on the dry film 3BS 2X 34:1998ii BSI 16 November 2005ForewordThis British Standard has been prepared by Technical Committee ACE/44 and is one of a series for paints and varnishes suitable for aerospa
7、ce purposes. It covers two types of cold curing polyurethane finish. This British Standard supersedes BS X 34:1991 which has been withdrawn. During its preparation the layout has been aligned with other BS X series standards and all references have been revised.The start and finish of text introduce
8、d or altered by amendment is indicated in the text by tags !“. Tags indicating changes to the text carry the number of the amendment. For example, text altered by amendment 1:2005 is indicated by !“.It has been assumed in the drafting of this British Standard that execution of its provisions is entr
9、usted to appropriately qualified and experienced people.The quality assurance authority and approving authority referred to in this British Standard are as stated in the contract or order, or the accredited representative of the authority stated, as instructed by the purchaser.WARNING. This British
10、Standard calls for the use of substances and/or procedures that may be injurious to health if adequate precautions are not taken It refers only to technical suitability and does not absolve the user from legal obligations relating to health and safety at any stage.This publication does not purport t
11、o 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 pagesThis document comprises a front cover, an inside front cover, pages i and ii, pages 1 t
12、o 6, an inside back cover and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.BS 2X 34:1998 BSI 16 November 200511 ScopeThis British Standard specifies requirements for the materials and performance of two types of two pack polyurethane fi
13、nish, for air-drying at ambient temperature, in a range of gloss levels, for aerospace applications.Type A materials are intended for interior and exterior use where maximum resistance to fluid attack is required.Type B materials are intended for exterior surfaces, and offer increased tolerance to f
14、lexing compared with type A materials.The polyurethane finish, as part of a paint scheme including a primer, is intended for application to metallic and non-metallic surfaces to give protection against corrosion and resistance to aircraft fluids and to offer surface appearance in terms of colour and
15、 level of gloss as specified by the purchaser.Information on application for type approval is provided in Annex A.2 Normative referencesThis British Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are made at the appropriate places
16、 in the text and the cited publications are listed on page 6. For dated references, only the edition cited applies; any subsequent amendments to or revisions of the cited publication apply to this British Standard only when incorporated in the reference by amendment or revision. For undated referenc
17、es, the latest edition of the cited publication applies, together with any amendments.3 DefinitionsFor the purposes of this British Standard the definitions given in BS 2015 apply.4 Materials4.1 CompositionThe paint shall consist of a pigmented base and an aliphatic isocyanate curing agent. The base
18、 and curing agent shall be mixed in simple proportions by volume and thinned as necessary with the appropriate thinners as recommended by the manufacturer.4.2 Scheme components4.2.1 GeneralComponents used in tests on the paint as part of a paint scheme shall conform to 4.2.2 and 4.2.3.4.2.2 PrimerTh
19、e primer shall conform to type B of BS X 33 unless otherwise specified.4.2.3 FinishThe finish shall conform to this British Standard.NOTE. The performance of a scheme including components otherwise specified may be suitable but should be separately assessed5 Performance5.1 General5.1.1 The test pane
20、ls shall be prepared and coated as described in Annex B.5.1.2 Unless otherwise specified, all tests shall be carried out in temperature and relative humidity conditions conforming to BS EN 23270.5.2 Tests on liquid paintThe finish shall conform to Table 1.BS 2X 34:19982 BSI 16 November 20055.3 Tests
21、 on the dry filmThe dry film of the paint system comprising primer and finish, prepared in accordance with Annex B, shall conform to Table 2.6 Batch inspectionBefore despatch, a representative sample of each batch of material, taken in accordance with BS EN 21512, shall be tested to confirm conformi
22、ty to tests 1, 4, 5 and 6 of Table 1, and, when prepared in accordance with Annex B, the scheme shall conform to tests 1, 2, 4 and 6 of Table 2.NOTE. Samples of material and material ingredients may be inspected at any stage of manufacture, and from any portion of the batch.Table 1 Tests on liquid p
23、aintTest Test panel, preparation and paint systemConditions Test method Requirement1) Condition Components in their original or laboratory containersBS EN ISO 1513 Shall be free from extraneous matter and shall show no skinning, gelling, hard settlement or other defect that may prevent satisfactory
24、application of a defect-free film.2) Volatile organic compound (VOC) content When prepared for application as specified in B.3.1!Process Guidance Note PG6/40“ 1Shall be less than or equal to the reference value1).3) Shelf life After 12 months at 5 C to 35 C, components in their original containersTe
25、sts 1), 5) and 6) of this tableShall conform to the requirements.4) Pot life !4 h unless otherwise agreed between manufacturer and purchaser“BS EN ISO 2431 Viscosity shall not increase by more than a factor of two from the initial value, unless otherwise specified by the purchaser.5) Application B.1
26、.1, B.1.3 and B.3 (without primer)24 h after applicationVisual examination with normal corrected visionPaint film shall show an opaque even finish, free from runs, sags, wrinkling, pin-holing or other defect.6) Drying time B.1.1, B.1.3 and B.3 (without primer)After application BS EN 29117 Paint film
27、 shall be through-dry at k6 h from application, unless otherwise specified by the purchaser.1)The reference value shall be established during type approval unless agreed otherwise between manufacturer and purchaser (see Annex A).BS 2X 34:1998 BSI 16 November 20053Table 2 Tests on the dry filmTest Te
28、st panel, prepaation and paint systemConditions Test method Requirement1) Colour B.1.1, B.1.3 and B.324 h after application, under diffuse daylightBS 3900: Part D1 Shall match the colour specified by the purchaser.2) Specular gloss B.1.1, B.1.3 and B.324 h after application, using a 60 glossmeterBS
29、3900: Part D5 Shall be as follows: high gloss: 85 units or above; semi matt: (15 3) units matt: less than or equal to 5 units.3) Flexibility (cupping test)B.1.1, B.1.3 and B.3 BS EN ISO 1520 (10 magnification)Type B: there shall be no cracking at an indentation depth of 4 mm4) Flexibility (impact)B.
30、1.1, B.1.2 and B.3 BS EN ISO 6272 (coating downwards)Type B: there shall be no cracking at an indentation depth of 3.8 mm5) Adhesion (cross hatch)B.1.1, B.1.3 and B.3 BS 3900: Part E6, 1 mm spacingkclass 16) Hardness (scratch)B.1.1, B.1.3 and B.3 BS 3900: Part E2 There shall be no penetration of the
31、 needle to the primer under a load of 1 500 g.7) Water resistance B.1.1, B.1.3 and B.3Immerse for 168 h at (40 2) C in water conforming to at least grade 3 ofBS EN ISO 3696a) Method 1, procedure A of BS 3900: Part G5k2 min after removal shall show no blistering or other film defects.b) BS 3900: Part
32、 E6, 1 mm spacingk2 min after removal, adhesion shall be kclass 1.c) BS 3900: Part E2 k2 min after removal shall show no penetration of the needle to the primer under a load of 1 500 g.8) Hydraulic fluid resistanceB.1.1, B.1.2 and B.3Cut paint film through to substrate down middle of panel; immerse
33、at(70 2) C in tri-n-butylphosphate; type A: 1 000 h; type B: 168 ha) Method 1, procedure A of BS 3900: Part G51 h after removal shall show no blistering or other film defects.b) BS 3900: Part E2; scratch (10 2) mm parallel to the cut1 h after removal shall show no penetration of the needle to the pr
34、imer under the following load: type A: 1 200 g; type B: 1 000 g.BS 2X 34:19984 BSI 16 November 2005Table 2 Tests on the dry film (continued)7 MarkingIn addition to any statutory requirements each container shall be legibly and durably marked with at least the following:a) a description of the materi
35、al;b) the number and date of this British Standard, i.e. BS 2X 34:1998;c) the type of material, i.e. type A or type B;d) the colour (with the colour standard if appropriate);e) the gloss category;f) the manufacturers name and recognized trade mark;g) the batch number;h) the date of manufacture;i) mi
36、xing and thining instructions.Test Test panel, prepaation and paint systemConditions Test method Requirement9) Artificial weatheringB.1.1, B.1.3 and B.3BS 3900: Part F16, method A. Lamps: UV-B (313); total duration 500 ha) BS EN ISO 1520 Type B: there shall be no cracking at an indentation depth of
37、4 mmb) BS 3900: Part D5High gloss and semi matt: gloss reduction shall be k20 % of initial value.c) BS 3900: Parts D8, D9 and D10%Eab*k 2.0BS 2X 34:1998 BSI 16 November 20055Annex A (normative) Type approvalA.1 When the manufacturer is required to prove product conformity to this British Standard, t
38、he following shall be provided:a) test results conforming to this British Standard;b) wet samples of all materials;c) a declaration of composition, including the percentage and nature of all ingredients;d) reference values if required, e.g. VOC content.A.2 After type approval has been granted, there
39、 shall be no change in the product formulation unless this is approved by the approving authority.Annex B (normative) Preparation of test panelsB.1 Preparation of substrateB.1.1 Use test panels made from unabraded aluminium sheet conforming to BS L 163:1978, and measuring approximately 150 mm 100 mm
40、 and 0.8 mm thick.B.1.2 Where specified (see Table 1 and Table 2), pickle the panels in accordance with BS EN 2334.B.1.3 Where specified (see Table 1 and Table 2), detergent degrease the panels as follows. Remove protective oil or grease either by vapour degreasing or solvent washing in accordance w
41、ith BS EN ISO 1514. Allow to dry and immerse in a 10 % aqueous solution of aircraft cleaning detergent conforming to DEF STAN 79-17 3 for 15 min. Remove and wash with running tap water for 1 min. Check that a water break-free surface is obtained. Rinse with water conforming to at least grade 3 of BS
42、 EN ISO 3696, and allow to dry.B.2 Primer applicationB.2.1 Prepare the primer by mixing the base and curing agent in the proportions specified and thin as necessary with the appropriate thinners as recommended by the manufacturer.B.2.2 Spray the primer on the test panels prepared in accordance with
43、B.1, within 24 h of preparation, at a spreading rate sufficient to produce a single dry coat with a film thickness of (20 5) 4m, unless otherwise specified, and allow to dry vertically, with free air access, for 4 h to 16 h, unless otherwise specified.B.3 Finish applicationB.3.1 Prepare the finish b
44、y mixing the base and curing agent in the proportions specified and thin as necessary with the appropriate thinners as recommended by the manufacturer.B.3.2 Spray the finish to the test panels, primed in accordance with B.2, at a spreading rate sufficient to produce a single dry coat with a film thi
45、ckness of (40 5) 4m, unless otherwise specified, and allow to dry vertically with free air access for at least 7 d, unless otherwise specified.BS 2X 34:1998 BSI 16 November 20056List of references (see Clause 2)Normative referencesBSI publicationsBRITISH STANDARDS INSTITUTION, LondonBS 2015:1992, Gl
46、ossary of paint and related terms.BS 3900, Methods of test for paints.BS 3900: Group D, Optical tests on paint films.BS 3900: Part D1: 1978, Visual comparison of the colour of paints.BS 3900: Part D5: 1995, Measurement of specular gloss of non-metallic paint films at 20, 60 and 85.BS 3900: Part D8:
47、1986, Determination of colour and colour difference Principles.BS 3900: Part D9: 1986, Determination of colour and colour difference Measurement.BS 3900: Part D10: 1986, Determination of colour and colour difference Calculation.BS 3900: Group E, Mechanical tests on paint films.BS 3900: Part E2: 1992
48、, Scratch test.BS 3900: Part E6: 1992, Cross cut test.BS 3900: Group G, Environmental tests on paint films (including tests for resistance to corrosion and chemicals).BS 3900: Part G5: 1993, Determination of resistance to liquids General methods.BS L 163:1978, Specification for sheet and strip of al
49、uminum-coated aluminumcoppermagnesiumsiliconmanganese alloy (solution treated, cold-worked for flattening and aged at room temperature) (Cu 4.4, Mg 0.5, Si 0.8, Mn 0.8).BS 2X 33:1998, Specification for two component epoxy primer for aerospace purposes.BS EN 23341), Specification for acid chromate pickle for aluminum alloys.BS EN 23270:1991, Specification for temperatures and humidities for conditioning and testing paints, varnishes and their raw materials.BS EN 29117:1992, Paints and varnishes Determination o
