BS 5617-1985 Specification for urea-formaldehyde (UF) foam systems suitable for thermal insulation of cavity walls with masonry or concrete inner and outer leaves《适用于砖砌或混凝土内外层空心墙保温.pdf

1、BRITISH STANDARD BS 5617:1985 Specification for Urea-formaldehyde (UF) foam systems suitable for thermal insulation of cavity walls with masonry or concrete inner and outer leaves UDC 678.6524121:692.232.2:699.86BS5617:1985 This British Standard, having been prepared under the directionof the Plasti

2、cs StandardsCommittee, was published under the authority ofthe Board of BSI and comes intoeffect on 31July1985 BSI 07-1999 First published August 1978 First revision July 1985 The following BSI references relate to the work on this standard: Committee reference PLM/46 Draft for comment 85/35764 DC I

3、SBN 0 580 14652 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Plastics Standards Committee (PLM/-) to Technical Committee PLM/46, upon which the following bodies were represented: Association of Building Component Manufacturers Ltd.

4、Brick Development Association British Board of Agrment British Plastics Federation British Rigid Urethane Foam Manufacturers Association British Urethane Foam Contractors Association (BUFCA) Calcium Silicate Brick Association Limited Chief and Assistant Chief Fire Officers Association Department of

5、the Environment (Building Research Establishment) Department of the Environment (Building Research Establishment FireResearch Station) Department of the Environment (Housing and Construction Industries) Department of the Environment for Northern Ireland Department of the Environment (Property Servic

6、es Agency) Engineering Equipment and Materials Users Association Fire Offices Committee Flat Roofing Contractors Advisory Board Greater London Council Institute of Refrigeration Ministry of Defence National Cavity Insulation Association National Coal Board National Federation of Roofing Contractors

7、National House-building Council Phenolic Foam Manufacturers Association Royal Institute of British Architects Shipowners Refrigerated Cargo Research Association Structural Insulation Association The following bodies were also represented in the drafting of the standard, through subcommittees and pan

8、els: Building Employers Confederation Eurisol (UK) Association of Manufacturers of Mineral Insulation Fibres Welwyn Hall Research Association Amendments issued since publication Amd. No. Date of issue CommentsBS5617:1985 BSI 07-1999 i Contents Page Committees responsible Inside front cover Foreword

9、ii 0 Introduction 1 1 Scope 1 2 Definitions 1 3 Property requirements 1 4 Processing requirements 2 5 Shelf-life limitations of foam system components 3 Appendix A Method for determination of effective density 4 Appendix B Method for determination of linear shrinkage 4 Appendix C Method for determin

10、ation of water absorption 5 Appendix D Method for determination of wet density 5 Appendix E Method for determination of foam system gel time 6 Appendix F Method for determination of foam system stability 7 Appendix G Method for determination of foam system appearance 7 Appendix H Method for determin

11、ation of solid resin yield 7 Appendix J Method for determination of free formaldehyde content of UF resin 7 Appendix K Method for determination of water tolerance of UF resin 8 Appendix L Method for determination of total acidity of foaming hardeners 9 Appendix M Method for determination of resin vi

12、scosity by the break time method 9 Figure 1 Test sample for effective density and shrinkage tests 4 Figure 2 Determination of foam system gel time 6 Table 1 Property requirements: type tests 2 Table 2 Property requirements: quality control tests 2 Table 3 Limiting values and permissible deviations f

13、or foam system components 2 Table 4 UF resin: shelf-life limitations 3 Table 5 Water tolerance conversion 9 Publications referred to Inside back coverBS5617:1985 ii BSI 07-1999 Foreword This revision of BS 5617, which has been prepared under the direction of the Plastics Standards Committee, superse

14、des BS5617:1978 which is withdrawn. The successful insulation of external cavity walls still relies on two standards, i.e.this standard, which specifies requirements for the foam systems which would be suitable for the application and the second standard, BS5618 which is the code of practice used by

15、 the installation contractor to satisfactorily install suitable foam systems. Accordingly, BS 5617 addresses the interface between the foam system supplier and the installation contractor, and BS5618 that between the installation contractor and his client. In this revision the foam systems have been

16、 restricted to use in cavities with masonry or concrete inner and outer leaves, requirements relating to the activities of the installation contractor have been removed (and placed as recommendations in the revision of BS5618), and the property requirements made more stringent. Attention is drawn to

17、 the fact that the urea-formaldehyde resins used for foam system production have a limited shelf-life: during storage they will ultimately undergo changes and become unsuitable for use. It is therefore important that the manufacturers recommendations with regard to storage should be observed if the

18、maximum storage life is to be obtained. Also foam systems differ according to the source of supply of the UF resin and the foaming hardener, and certain properties listed in Table 2 to Table 4 have therefore been given tolerances rather than specific values. A British Standard does not purport to in

19、clude 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 itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pag

20、esi andii, pages1 to10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS5617:1985 BSI 07-1999 1 0 Introduction A urea-formaldehyde foam syste

21、m is generated at the point of injection from a mixture of aqueous resin solution, aqueous foaming hardener solution and air. The resin and hardener solutions are supplied at controlled rates to suitable foam system generating equipment from pressurized pots or by a pumping system. The foam system,

22、which is fluid at the time of injection into the cavity, sets shortly afterwards by chemical reaction. This chemical reaction continues and simultaneously loss of residual water occurs by absorption by and subsequent evaporation from the wall to produce the final foam. Urea-formaldehyde foam systems

23、 complying with this standard have a fine, uniform, cellular structure which is vapour permeable. The foam is durable and has sufficient strength to be self-supporting in the cavity. Because chemical reactions are taking place during the foam system injection process, some variation in foam properti

24、es can occur due to differences in in situ operating conditions. Foam system tests are carried out on site prior to injection to ensure that the quality of the system to be injected complies with this standard. These aspects are detailed in BS5618. The thermal insulation is achieved by the foam rest

25、ricting air circulation in the cavity and by limiting radiation losses without adding substantially to the conducted heat loss. Its performance is therefore primarily determined by the extent to which the cavity is filled rather than by variations in the foam density. 1 Scope This British Standard s

26、pecifies the property requirements, the properties of the components and the production parameters, of urea-formaldehyde foam systems suitable for injection into external masonry or concrete cavity walls to provide improved thermal insulation. NOTEThe titles of the publications referred to in this s

27、tandard are listed on the inside back cover. 2 Definitions For the purposes of this British Standard the following definitions apply: 2.1 urea-formaldehyde (UF) foam an infusible cellular matrix of cured urea-formaldehyde resin insoluble in water and other common solvents 2.2 urea-formaldehyde (UF)

28、foam system a mixture of urea-formaldehyde resin, hardener, surfactant, water, air and water additives 2.3 foaming hardener a mixture of surface active agents and acids that enables a foam system to be produced by the introduction of air into an aqueous solution and will cause UF resin, when mixed i

29、nto the foam system, to set to an insoluble, infusible matrix 2.4 cavity an air space between two leaves of an external wall 2.5 effective density (ED) the mass of a specified sample divided by its initial volume using the method described in Appendix A 2.6 declaration the document supplied by the f

30、oam system supplier to the purchaser or to any authorized testing or approvals organization, containing relevant details for the proper use of the foam system 3 Property requirements NOTEThe quality of the foam system depends on the choice of components (see 4.1) and their method of application as d

31、eclared by the foam system supplier (see4.2). 3.1 Type tests The UF foam system shall be such that the foam produced, when tested in accordance with the methods given in Table 1, with samples prepared in accordance with the declaration of the foam system supplier as specified in4.2, shall comply wit

32、h the property requirements also given in Table 1. The samples required for the type tests given in Table 1 shall be conditioned to constant mass, at23 2 C and63 5 % r.h., after being allowed to dry naturally for a period of three weeks. 3.2 Quality control tests NOTEDetails of when these tests are

33、to be carried out are given in6.5 of BS5618:1985. When tested in accordance with the methods given in Table 2, with samples prepared in accordance with the declaration of the foam system supplier as specified in4.2, the UF foam system shall comply with or, as appropriate, be such that the foam produ

34、ced complies with the quality control requirements also given in Table 2.BS5617:1985 2 BSI 07-1999 4 Processing requirements 4.1 Foam system components The application of the two foam system components, an aqueous solution of a urea-formaldehyde resin and an aqueous solution of a foaming hardener sh

35、all be as declared by the foam system supplier as specified in4.2. The values of the properties given in Table 3 for the system components shall be declared for each foam system by the system supplier. The components shall then comply with the permissible deviations and limiting values given in Tabl

36、e 3. Table 1 Property requirements: type tests Table 2 Property requirements: quality control tests Table 3 Limiting values and permissible deviations for foam system components Property Requirement Test method Linear shrinkage, % max. Water absorption, kg/m 2max. Thermal conductivity, W/(mK) max. R

37、esistance to microbial attack Ignitability Burning characteristics a 8 2 0.035 No attack Class P Extent of burning not to exceed125 mm Appendix B Appendix C Method7 of BS4370-2:1973 Method3 of BS1982:1968 BS476-5 BS4735 NOTE 1Because UF foam chars on contact with flame and emits little smoke, the pr

38、esence of foam tends to reduce the risk of fire and smoke spread via the cavity. However, the use of UF cavity insulation does not affect requirements for the provision of cavity barriers. NOTE 2For design purposes an effective thermal conductivity value for UF foam installed in masonry cavity walls

39、 should be taken to be 0.04 W/(mK). This aspect is more fully discussed in Appendix J of BS 5618:1985. a CAUTION. The small scale laboratory test described in BS4735:1974 is solely for assistance in monitoring consistency of production and is not for use as a means of assessing the potential fire ha

40、zard of a material in use. Property Requirements or limiting values Permissible deviations Test method Effective density, kg/m 3 Linear shrinkage, % max. Wet density, kg/m 3 Gel time, s Foam stability Appearance Target value specified by the system supplier 10 Target value specified by the system su

41、pplier To be within the limits specified by the system supplier Does not collapse Uniform, fine cellular structure 25 % 20 % Appendix A Appendix B Appendix D Appendix E Appendix F Appendix G Property Limiting values and permissible deviations on declared values Test method UF resin: Solid resin yiel

42、d, % m/m Density, g/mL Viscosity, mPas Free formaldehyde content, % m/m Water tolerance, % V/V Foaming hardener: Total acidity, % m/m Surfactant concentration, % KOH m/m 2 1.5 % 30 % Between0 and1 100 2 10 Appendix H Use a hydrometer complying with BS718 Method1 of BS5350-B8:1977 Appendix J Appendix

43、 K Appendix L To be specified by system supplierBS5617:1985 BSI 07-1999 3 4.2 Declaration The foam system supplier shall make a declaration for each foam system with respect to the following parameters. a) The dilution at which the UF resin is to be used and the dilution procedure. b) The dilution a

44、t which the foaming hardener is to be used and the dilution procedure. c) The ratio to be used of the diluted UF resin to the diluted foaming hardener. d) Any water hardness limitations and the method of correction. e) The method of coping with variations in operating temperatures. f) The data requi

45、red in Table 2, the values of the properties given in Table 3 and the usable limits as required in Table 4. 5 Shelf-life limitations of foam system components 5.1 UF resin NOTEThe urea-formaldehyde resins of the type used for foam system production have a limited shelf-life. During storage they unde

46、rgo changes and will ultimately become unsuitable for use. The foam system supplier shall ensure that UF resins for use in UF foam systems specified by this standard shall remain usable for a period of3months when stored at temperatures up to20 C. The period shall be counted from the quality control

47、 release date and shall be stated for each container. To ensure that UF foam system quality is not affected by the ageing of the UF resin the foam system supplier shall define usable limits for the resins in respect of the properties given in Table 4. 5.2 Foaming hardener If there are shelf-life lim

48、itations on foaming hardener they shall be stated by the foam system supplier. Table 4 UF resin: shelf-life limitations Property Usable limits Test method Maximum viscosity, s Minimum water tolerance, % V/V To be specified by the system supplier Appendix M Appendix KBS5617:1985 4 BSI 07-1999 Appendi

49、x A Method for determination of effective density A.1 Principle The effective density is obtained from the sample by relating its dried mass to its original volume. A.2 Test sample A cylindrical shaped sample shall be produced in a polyethylene bag which is slightly greater in circumference than the internal circumference of the tube into which it is placed. A.3 Apparatus A.3.1 Rigid tube, approximately450 mm long and approximately200 mm internal diameter. A.3.2 Polyethylene bag, of length approximately1000 mm