1、BRITISH STANDARD BS 3958-3: 1985 Specification for Thermal insulating materials Part 3: Metal mesh faced man-made mineral fibre mattresses UDC 662.998:677.52.076.4BS3958-3:1985 This British Standard, having been prepared under the direction of the Refrigeration, Heating and Air Conditioning Standard
2、s Committee, was published under the authority of the Board of BSI and comes into effect on 30 September 1985 BSI 07-1999 First published December 1967 First revision The following BSI references relate to the work on this standard: Committee reference RHE/9 Draft for comment 84/72312 DC ISBN 0 580
3、14585 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Refrigeration, Heating and Air Conditioning Standards Committee (RHE/-) to Technical Committee RHE/9, upon which the following bodies were represented: British Ceramic Research Asso
4、ciation British Gas Corporation Chartered Institution of Building Services Combustion Engineering Association Cranfield Institute of Technology Department of Health and Social Security Department of the Environment (Building Research Establishment) Department of Trade and Industry (National Physical
5、 Laboratory) Electricity Supply Industry in England and Wales Engineering Equipment and Materials Users Association Eurisol (UK) Association of Manufacturers of Mineral Fibre Insulation Gypsum Products Development Association Institution of Gas Engineers Refrigeration Industry Board Royal Institute
6、of British Architects Structural Insulation Association Thermal Insulation Manufacturers and Suppliers Association (TIMSA) Thermal Insulations Contractors Association Water-tube Boilermakers Association Amendments issued since publication Amd. No. Date of issue CommentsBS3958-3:1985 BSI 07-1999 i Co
7、ntents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Definitions 1 3 Sampling and testing 1 4 Composition 1 5 Metal facings and ties 1 6 Moisture content 1 7 Physical requirements 1 8 Fire classification 2 9 Chemical requirements 2 10 Dimensional tolerances 3 11 Marking 3 Ap
8、pendix A Information to be supplied when ordering 4 Appendix B Method of test for compressibility and resilience 4 Appendix C Method of test for pH value of water extract 4 Table 1 Thermal conductivity values 1 Publications referred to Inside back coverBS3958-3:1985 ii BSI 07-1999 Foreword This revi
9、sion of this Part of BS3958is one of a series published under the direction of the Refrigeration, Heating and Air Conditioning Standards Committee to specify requirements for a particular range of insulating materials. It supersedes the1967edition which is withdrawn. Other Parts of BS3958are: Part 1
10、: Magnesia preformed insulation; Part 2: Calcium silicate preformed insulation; Part 4: Bonded preformed man-made mineral fibre pipe sections; Part 5: Bonded mineral wool slabs (for use at temperatures above50C); Part 6: Finishing materials; hard setting composition, self-setting cement and gypsum p
11、laster. 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 itself confer immunity from legal obligations. Summary of pages This document co
12、mprises a front cover, an inside front cover, pages i and ii, pages 1 to 4, 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.BS3958-3:1985 BSI 0
13、7-1999 1 1 Scope This Part of BS3958 specifies composition, moisture content, physical and chemical requirements for man-made mineral fibre mattresses for thermal insulating purposes, faced on one or both sides with a flexible metal mesh. Information to be supplied when ordering is given in Appendix
14、 A. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this Part of BS3958, the definitions given in BS874, BS2972 and BS3533 apply. 3 Sampling and testing Sampling and testing shall be in accordance with the appropr
15、iate clause in BS2972. The metal facings and ties shall not be removed except where stated in the relevant clauses. 4 Composition The insulation material shall be of man-made mineral fibre made from rock, slag or glass, and shall not contain non-fibrous pieces of these materials that have any dimens
16、ion exceeding10mm. NOTEThe fibres may be lightly bonded with a thermosetting binder, or may be treated with an oil dust-suppressant. See 9.2. 5 Metal facings and ties The mattress shall be suitably faced with woven wire mesh or expanded metal, and held together by wire or twine extending from one fa
17、ce to the other, spaced not more than120mm apart. The ties shall not become detached from the facings when pressure is applied over the surface of the mattress. NOTE 1The following materials are suitable facing materials and are normally available as standard products. a) Woven wire mesh. Mild steel
18、,25mm mesh,1.2mm to0.6mm diameter wire, galvanized after weaving. b) Expanded metal. Mild steel, diamond shaped mesh6mm to10mm shortway of mesh (SWM),0.45mm thick strands, mass1.22kg/m 2 , with or without galvanized finish. NOTE 2When required for use at high temperature suitable heat resistant faci
19、ngs and ties should be specified. Particular attention is drawn to the limitations of galvanized finishes. See33.17.1 of BS5970:1981. 6 Moisture content When conditioned at high humidity in accordance with 40.4 of BS2972:1975, the moisture content of the materials shall not exceed5% by mass. 7 Physi
20、cal requirements 7.1 Thermal conductivity When tested in accordance with the appropriate method of test for thermal conductivity given in BS874, the thermal conductivity shall not exceed the values given inTable 1. Table 1 Thermal conductivity values NOTE 1BS874requires the test report to state whic
21、h method of test was employed, the bulk density of the material, the hot face temperature and cold face temperature (generally within the range10C to50 C), the conditioning procedure and the moisture content before and after test. NOTE 2In order to comply with the requirements of Table 1, products o
22、f different bulk density may be supplied for use at different service temperatures. Mean temperature Thermal conductivity C 50 100 150 200 250 300 350 W/(mK) 0.042 0.050 0.060 0.073 0.090 0.110 0.130BS3958-3:1985 2 BSI 07-1999 NOTE 3Not all products are designed to operate at the highest temperature
23、 in Table 1; conversely, there are materials which can be used at higher temperatures; it is important, therefore, to take note of the manufacturers declared maximum service temperature. NOTE 4In calculations of heat loss, only the thickness of the insulating material is relevant; where the metal fa
24、cing is of substantial thickness, a suitable correction should be applied by subtracting the total thickness of the facings from the nominal thickness of the mattress. Metal ties of heavy gauge may also increase the conductivity of the mattress. 7.2 Bulk density For any particular product, the varia
25、tion from the manufacturers declared value for bulk density, calculated at the nominal thickness, shall not exceed 15 %. NOTEThe bulk density of the material, excluding metal facings and ties, will normally lie within the range50kg/m 3to150 kg/m 3 . 7.3 Limiting temperature and thickness 7.3.1 The m
26、anufacturer shall state the maximum limiting temperature and limiting thickness at that temperature. 7.3.2 The material shall comply with the requirements of 18.1 to 18.3 of BS2972:1975. 7.3.3 When a sample is heated in accordance with 21.1 of BS2972:1975at the stated maximum limiting temperature of
27、 use, the material shall maintain its general form and not suffer visible deterioration of the fibrous structure. NOTEColour changes are not relevant. 7.4 Compressibility and resilience When tested by the method described in Appendix B, the thickness of the specimen whilst under pressure shall be no
28、t greater than the nominal thickness plus3mm. After removal of the pressure, the thickness shall be not less than the nominal thickness minus3mm. NOTEThe objects of this test are to ensure that a mattress supplied at greater than nominal thickness is sufficiently compressible to be fitted at its nom
29、inal thickness and that a mattress is sufficiently resilient to recover its nominal thickness after being subjected to compression. 7.5 Vibration settlement When tested in accordance with clause 28 of BS2972:1975, the settlement shall not exceed2 %. 8 Fire classification The mattress shall be non-co
30、mbustible when tested in accordance with BS 476-4. For the purposes of this test, the metal facings and ties shall be removed. NOTE 1Attention is drawn to the requirements of 27.1 of BS5422:1977. NOTE 2Some organic matter may be present either in a fibrous form or as a bonding agent. It is suggested
31、 that the composition of the product be checked with the manufacturer for use in process conditions where organics may present a hazard, e.g. processes involving powerful oxidizing agents, thermal insulation on pipework and plant in a flammable atmosphere. 9 Chemical requirements 9.1 pH value of wat
32、er extract When tested by the method described in Appendix C, the pH value recorded shall be between 6.0 and 9.0. 9.2 Corrosive attack The material shall not include significant quantities of substances that will promote corrosive attack on the surfaces with which it is to be in contact. NOTEWater-s
33、oluble chlorides are normally present in trace quantities in most commercial thermal insulating materials. In the presence of moisture and oxygen and under certain adverse metallurgical conditions chloride ions are capable of initiating stress corrosion cracking in susceptible metal alloys such as a
34、ustenitic stainless steels. It is not practicable to indicate a safe upper limit for chloride content since water can leach out soluble chlorides from substantial volumes of insulating materials and allow them to be concentrated at the metal-insulation interface. In addition, water from outside sour
35、ces such as the process itself or wind-driven spray can substantially increase the chloride content of the insulation. In conditions potentially conducive to stress corrosion cracking, appropriate safeguards should be adopted (see 33.17 of BS5970:1981). Where necessary, trace quantities of water-sol
36、uble chlorides may be estimated in accordance with section 22 of BS2972:1975.BS3958-3:1985 BSI 07-1999 3 10 Dimensional tolerances 10.1 Length and width The dimensions of the mattress shall be in accordance with the nominal dimensions stated by the manufacturer (or supplier, as appropriate), subject
37、 to the following tolerances: 10.2 Thickness The thickness shall be not less than the nominal thickness minus3mm when measured by the method given in 6.1 of BS2972:1975. NOTEAs these materials can be compressed, they are often supplied at a thickness substantially in excess of nominal in order to en
38、sure correct thickness after application. 11 Marking Each package containing mattresses complying with this standard, or the articles themselves, shall be clearly marked with the following: a) manufacturers name, mark or symbol; b) manufacturers type, designation and grade; c) dimensions; d) the num
39、ber and date of this British Standard, i.e. BS3958-3:1985 1) . length and width: + 15mm, 10mm for sizes up to0.5m + 3 %, 2 % for sizes over0.5m 1) Marking BS3958-3:1985 on or in relation to a product is a claim by the manufacturer that the product has been manufactured to the requirements of the sta
40、ndard. The accuracy of such a claim is therefore solely the manufacturers responsibility. Enquiries as to the availability of third party certification to support such claims should be addressed to the Director, Quality Assurance Division, PO Box 375, Milton Keynes MK14 6LO for certification marks a
41、dministered by BSI or to the appropriate authority for other certification marks.BS3958-3:1985 4 BSI 07-1999 Appendix A Information to be supplied when ordering The following information should be supplied when ordering: a) the number of this British Standard, i.e. BS3958-3; b) the dimensions of the
42、 mattress required; c) the type of metal facing, e.g. woven wire mesh or expanded metal, as in clause 5, or a special type of metal facing; d) whether the material is required faced on two sides or on one side only; e) the type of tie required, e.g. galvanized wire ties or a special type of tie to s
43、atisfy a particular requirement; f) a note of any unusual condition, e.g. of any acidic or alkaline fumes in the atmosphere around the insulation or of any other hazardous condition; g) the maximum temperature to which the product will be subjected. Appendix B Method of test for compressibility and
44、resilience B.1 Specimens Cut five specimens, each200mm 200mm, from the mattress sample. B.2 Procedure Remove all facings and ties from a specimen and place the specimen on a flat horizontal surface. Place on it a flat, stiff platten of dimensions 300mm 300mm and a mass of0.5 0.05kg. Apply a10kg load
45、 (equivalent to 2600 N/m 2 ) centrally to the platten and, after 5 min, determine the thickness of the specimen by measurements at the four corners of the platten. Remove the load and the platten, allow the specimen to expand freely for5min, replace the platten and measure the final thickness at the
46、 four corners of the platten with a steel rule. Appendix C Method of test for pH value of water extract C.1 Preparation of sample From the bulk sample, taken in accordance with BS2972, cut five pieces, each of approximate mass5g, from separate units where possible. Disintegrate these pieces and mix
47、thoroughly. C.2 Determination of pH value of water extract Weigh2g of the sample and shake well for10min with100mL of distilled or deionized water (pH6.5to7.5) at room temperature. Leave to settle for5min and decant the solution if necessary. Measure the pH of the mixture, using a standard pH meter
48、to BS3145. Repeat the test on a further2g of the sample and report both values.BS3958-3:1985 BSI 07-1999 Publications referred to BS 476, Fire tests on building materials and structures. BS 476-4, Non-combustibility test for materials. BS 874, Methods for determining thermal insulating properties, w
49、ith definitions of thermal insulating terms. BS 2972, Methods of test for inorganic thermal insulating materials. BS 3145, Specification for laboratory pH meters. BS 3533, Glossary of thermal insulation terms. BS 3958, Specification for thermal insulating materials 2) . BS 3958-1, Magnesia preformed insulation. BS 3958-2, Calcium silicate preformed insulation. BS 3958-4, Bonded preformed man-made mineral fibre pipe sections. BS 3958-5, Bonded mineral wool slabs (for use at temperatures above 50 C). BS 3958-6, Finishing materials; hard
