1、BRITISH STANDARD BS6283-2: 1991 Safety and control devices for use in hot water systems Part 2: Specification for temperature relief valves for pressures from1 bar to10 barBS6283-2:1991 This British Standard, having been prepared under the directionof the Building ServicesStandards Policy Committee,
2、 was published underthe authority of the BoardofBSI and comes intoeffecton 28 June1991 BSI06-1999 First published November1982 Second edition June1991 The following BSI references relate to the work on this standard: Committee referenceSEB/2 Draft for comment87/12745 DC ISBN 0 580 19245 8 Committees
3、 responsible for this British Standard The preparation of this British Standard was entrusted by the Building Services Standards Policy Committee (SEB/-) to Technical CommitteeSEB/2, upon which the following bodies were represented: Association of Manufacturers of Domestic Electrical Appliances Asso
4、ciation of Manufacturers of Domestic Unvented Supply Systems Equipment (MODUSSE) Association of Water Officers Ltd. British Bathroom Council British Gas plc British Non-ferrous Metals Federation British Plastics Federation British Plumbing Fittings Manufacturers Association British Valve and Actuato
5、r Manufacturers Association Builders Merchants Federation Consumer Policy Committee of BSI Department of the Environment (Building Research Establishment) Department of the Environment (Property Services Agency) Department of the Environment (Water Directorate) Department of Trade and Industry (Nati
6、onal Weights and Measures Laboratory) Institute of Clerks of Works of Great Britain Inc. Institute of Plumbing Institution of Gas Engineers Institution of Water and Environmental Management (IWEM) Metal Sink Manufacturers Association National Association of Plumbing, Heating and Mechanical Services
7、Contractors Royal Institute of British Architects Society of British Gas Industries South London Consortium Water Authorities Association Water Companies Association Water Heater Manufacturers Association Amendments issued since publication Amd. No. Date CommentsBS6283-2:1991 BSI 06-1999 i Contents
8、Page Committees responsible Inside front cover Foreword ii Section 1. General 1.1 Scope 1 1.2 Definitions 1 1.3 Nominal size 1 1.4 Marking 1 Section 2. Materials 2.1 General 2 2.2 Bodies and associated parts 2 2.3 Sealing and diaphragm materials 2 2.4 Spring materials 2 Section 3. Design and constru
9、ction 3.1 General 3 3.2 End connections and flow dimensions 3 3.3 Valve seat attachment 4 3.4 Guides and moving parts 4 3.5 Provision for deposits and drainage 4 3.6 Adjustment 4 3.7 Springs 4 3.8 Easing gear 4 Section 4. Performance 4.1 Production tests 7 4.2 Type tests 7 Appendix A Information to
10、be supplied by the purchaser 8 Appendix B Production tests 8 Appendix C Torque test 8 Appendix D Back pressure test 8 Appendix E Opening and reseating temperature test 8 Appendix F Discharge capacity test 9 Appendix G Water discharge test 9 Appendix H Endurance test 9 Figure 1 Typical arrangement of
11、 temperature relief valves 5 Figure 2 Test arrangement for opening and reseating temperatures 8 Figure 3 Test arrangement for discharge capacity 10 Table 1 Nominal size of valve 1 Table 2 Minimum dimensions of flow passages 3 Table 3 Maximum value of dimension X as shown in Figure 1 4 Table 4 Torque
12、 8 Publication(s) referred to Inside back coverBS6283-2:1991 ii BSI 06-1999 Foreword This Part of BS6283 has been prepared under the direction of the Building Services Standards Policy Committee at the request of the Department of the Environment on the advice of the Standing Technical Committee on
13、Water Regulations. It supersedes BS6283-2:1982 which is withdrawn. Each Part of BS6283 specifies requirements for a particular device for preventing overheating and/or excess pressures in water installations, and is intended to be suitable for citing as deemed to satisfy the relevant regulations or
14、byelaws. This British Standard comprises the following Parts: Part 1: Specification for expansion valves for pressures up to and including10 bar; Part 2: Specification for temperature relief valves for pressures from1 bar to10 bar; Part 3: Specification for combined temperature and pressure relief v
15、alves for pressures from1 bar to10 bar; Part 4: Specification for drop-tight pressure reducing valves of nominal size up to and including DN50 for supply pressures up to and including12 bar. A British Standard does not purport to include all the necessary provisions of a contract. Users of British S
16、tandards 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, pagesi andii, pages1 to10, an inside back cover and a back cover. This
17、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.BS6283-2:1991 BSI 06-1999 1 Section 1. General 1.1 Scope This Part of BS6283 specifies the design, construction and testing requirements fo
18、r temperature relief valves of the automatic reseating type, of nominal sizes DN15 to DN40 for working pressures from1 bar 1)to10 bar. The valves are intended for the protection of storage heaters of the unvented type that are required to operate at temperatures not normally exceeding 90C and not ex
19、ceeding100C under emergency conditions. However, they may be used for other water applications where appropriate. This Part of BS6283 does not cover the application or installation of these valves. Advice on the information to be supplied by the purchaser is given in Appendix A. NOTEThe titles of th
20、e publications referred to in this Part of BS6283 are listed on the inside back cover. 1.2 Definitions For the purposes of this Part of BS6283 the following definitions apply. 1.2.1 temperature relief valve a temperature actuated valve which opens automatically at a specified temperature to discharg
21、e fluid. It is fitted to water heaters to prevent the temperature in the container from exceeding100C 1.2.2 maximum working pressure the maximum static water pressure at which a temperature relief valve is designed to be used 1.2.3 set temperature the nominal temperature at which a temperature relie
22、f valve is set to open in service 1.2.4 reseating temperature the temperature at which a temperature relief valve closes after discharging 1.2.5 rated discharge capacity the power that can be dissipated through the temperature relief valve under the conditions described in the discharge capacity tes
23、t 1.3 Nominal size The nominal size of the temperature relief valve and the nominal size of the appropriate inlet connection shall be as given in Table 1. Table 1 Nominal size of valve 1.4 Marking 1.4.1 Flow marking Each temperature relief valve shall be legibly and permanently marked to identify th
24、e discharge connection. This marking shall be stamped, etched, cast or moulded on the valve. 1.4.2 Identification marking Each temperature relief valve shall be legibly and permanently marked with the following: a) the number of this British Standard, i.e.BS6283/2 2) ; b) the manufacturers or agents
25、 name, trademark or symbol; c) the name or model number of the valve and its nominal size; d) the month and year of manufacture, e.g.1291; e) the rated discharge capacity in kilowatts, to the nearest0.1kW; f) the set temperature inC. NOTEAdhesive labels complying with BS4781 are considered to be per
26、manent for the purposes of this Part of BS6283. 1) 1bar =10 5 N/m 2 =100 kPa. All pressures are gauge pressures unless otherwise stated. Nominal size of valve Nominal size of inlet connection Screwed (complying with BS2779 orBS21) Compression (complying with BS864-2) Flanged (complying with BS4504-2
27、 DN 15 20 25 32 40 1 1 1 15/18 22 28 35 42 15 20 25 32 40 2) Marking BS6283/2 on or in relation to a product represents a manufacturers declaration of conformity, i.e.a claim by or on behalf of the manufacturer that the product meets the requirements of the standard. The accuracy of the claim is the
28、refore solely the responsibility of the person making the claim. Such a declaration is not to be confused with third party certification of conformity, which may also be desirable.BS6283-2:1991 2 BSI 06-1999 Section 2. Materials 2.1 General Any non-metallic materials, under the conditions for which
29、the valve is designed, shall comply with BS6920-1. 2.2 Bodies and associated parts The bodies and associated parts of temperature relief valves shall be constructed from those materials specified in clause 9 of BS5412 and BS5413-5:1976. Materials that are in contact with water shall be capable of co
30、mplying with clause 7 of BS2872:1989. The sheath of the temperature sensing element shall be made of copper complying with BS2870 or BS2871 or of a nickel-copper (monel) alloy complying with BS3074. The temperature probe (sensing element) shall be protected by a coating or sleeve which shall show no
31、 visible evidence of degradation (e.g.blistering) during or following testing of the valve. 2.3 Sealing and diaphragm materials Sealing members and diaphragm materials shall comply with items3) and4) of clause 6 of BS3457:1973. They shall also be capable of complying with the test criteria in Append
32、ix C of BS5412 and BS5413-5:1976. 2.4 Spring materials Springs shall be made of one of the following: a) stainless steel complying with BS970-4 or BS2056; b) nickel-copper alloy (monel) complying with BS3075; c) phosphor bronze complying with grade PB102 ofBS2874; d) when not in contact with water,
33、carbon steel, complying with grades094A65HS and735A50HS of BS2803 or gradesHS2 andHS3 of BS5216.BS6283-2:1991 BSI 06-1999 3 Section 3. Design and construction 3.1 General Temperature relief valves shall be so constructed that failure of any part will not obstruct the free and full discharge from the
34、 valve. The valves shall not open under pressure alone at pressures below16bar. The inlet and discharge connections shall be unobstructed except for the portion of the temperature sensing element within the inlet of the temperature relief valve. The section of the element within the inlet shall not
35、exceed the limits given in Table 2. The thermally responsive material of temperature sensing elements shall be sealed against water entry. 3.2 End connections and flow dimensions 3.2.1 Type of connections 3.2.1.1 General End connections shall be screwed ends, compression ends or flanged ends complyi
36、ng with3.2.1.2, 3.2.1.3 or3.2.1.4 respectively. 3.2.1.2 Screwed ends Where the end connection is screwed, the thread shall be a parallel pipe thread complying with BS2779 for internal threads and class B of BS2779 or BS21 for external threads of lengths given in Table6 of BS864-2:1983. Screwed end c
37、onnections shall be designed so that when a pipe or fitting is screwed into the connection it shall not reduce the area of flow through the valve, distort any part of the valve body or adversely affect the operation of the valve. 3.2.1.3 Compression ends Where compression end connections are provide
38、d they shall comply with BS864-2 or BS864-5. 3.2.1.4 Flanged ends Where flanged end connections are provided they shall comply with Table9 of BS4504-3.3:1989. 3.2.2 Size of connections End connections shall be either the same nominal size as the valve (see Table 1) or, in the case of discharge conne
39、ctions only, one size larger than the nominal size of the valve. Temperature relief valves with rated discharge capacities up to and including7.5kW shall be not smaller than DN15. Temperature relief valves with rated discharge capacities exceeding7.5kW shall be not smaller than DN20. The minimum int
40、ernal diameter of end connections shall be as given in Table 2. 3.2.3 Total flow area The minimum total flow area at any point within the valve body, other than at the end connections and at the seating, shall be as given in Table 2. Where the total flow area is divided into two or more flow passage
41、s in parallel, the minimum flow area of any such passage shall be as given in Table 2. Calculation of total flow area shall exclude any portion in a corner of the flow area that would not be included in a5mm diameter circle positioned tangentially to two sides of the flow area. 3.2.4 Width of passag
42、es 3.2.4.1 The clearance around the shroud shall be as shown in Figure 1(e) and Figure 1(f). 3.2.4.2 The smallest cross-sectional dimension of all the other flow passages shall be not less than5mm, except when the smallest dimension of the flow area below the lip of the shroud is at least5mm, in whi
43、ch case the clearance between the valve body wall and the valve shroud shall be not less than1.5mm (seeFigure 1). Table 2 Minimum dimensions of flow passages (see Figure 1) Nominal size of valve Minimum internal diameter of end connections (see3.2.2) Minimum total flow area (see3.2.3) Minimum flow a
44、rea of any body passage (see3.2.3) Maximum diameter of the portion of sensing element within the valve inlet (see3.1) a Minimum volume under seating bore DN 15 20 25 32 40 mm 14 18 24 32 38 mm 2 200 344 558 968 1316 mm 2 100 172 279 484 658 mm 7 8 11 14 17 mL 5 7 10 14 17 a These dimensions include
45、the protective coating or sleeve.BS6283-2:1991 4 BSI 06-1999 3.2.4.3 The flow-way between the walls of the orifice and any part of a temperature sensing element extending through the orifice may be less than5mm, but it shall be not less than3mm. The minimum dimension between any part of a temperatur
46、e sensing element below the orifice, which is larger than that part extending through the orifice, and the lower edges of the orifice shall be5mm (seeFigure 1). 3.2.5 Minimum seating bore Temperature relief valves shall have a seating bore, B, of not less than11mm diameter. The minimum volume under
47、the seating bore shall be as given in Table 2. The volume under the seating excludes any volume contained within the inlet connection. If the seating bore diameter is less than90% of the minimum internal diameter of end connections given in Table 2, the length of the seating bore shall not exceed th
48、e seating bore diameter. However, twice the length shall be permissible until January1994. 3.3 Valve seat attachment Where separate seats are fitted to the valve disc or body they shall be secured to prevent them from working loose or blowing out. 3.4 Guides and moving parts Means shall be provided
49、to guide the valve disc and to prevent it from being misaligned during working. Disc guides shall be located on the discharge side of the valve, except that shallow conical self-centring guides integral with the disc may be used on the inlet side see Figure 1(c). Wing or similar guides shall not be used on the inlet side of the valve seeFigure 1(d). Moving parts shall have sufficient clearance to ensure freedom of movement under the intended conditions of service. 3.5 Provision for deposits and drainage The outlet from a tempe
