1、 MSS SP-133-2010 Excess Flow Valves for Low Pressure Fuel Gas Appliances Standard Practice Developed and Approved by the Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. 127 Park Street, NE Vienna, Virginia 22180 Phone: (703) 281-6613 Fax: (703) 281-6671 e-mail: infomss
2、-hq.org www.mss-hq.org MSS STANDARD PRACTICE SP-133i This MSS Standard Practice was developed under the consensus of the MSS Technical Committee 501 and the MSS Coordinating Committee. The content of this Standard Practice is the result of the efforts of competent and concerned volunteers to provide
3、 an effective, clear, and non-exclusive specification that will benefit the industry as a whole. This MSS Standard Practice is intended as a basis for common practice by the manufacturer, the user, and the general public. The existence of an MSS Standard Practice does not in itself preclude the manu
4、facture, sale, or use of products not conforming to the Standard Practice. Mandatory conformance is established only by reference in a code, specification, sales contract, or public law, as applicable. “Unless otherwise specifically noted in this MSS Standard Practice, other standards documents refe
5、rred to herein are identified by the date of issue that was applicable to this Standard Practice at the date of issue of this Standard Practice. See Annex A. This Standard Practice shall remain silent on the applicability of those other standards of prior or subsequent dates of issue even though app
6、licable provisions may not have changed. References contained herein which are bibliographic in nature are noted as supplemental in the text.” In this Standard Practice all notes, annexes, tables, and figures are construed to be essential to the understanding of the message of the standard, and are
7、considered part of the text unless noted as “supplemental“. All appendices, if included, that appear in this document are construed as “supplemental“. Supplemental information does not include mandatory requirements for this Standard Practice. Substantive changes in this 2010 edition are “flagged” b
8、y parallel bars as shown on the margins of this paragraph. The specific detail of the change may be determined by comparing the material flagged with that in the previous edition. U.S. customary units in this Standard Practice are the standard; (SI) metric units are for reference only. Non-tolerance
9、d dimensions in this Standard Practice are nominal, and, unless otherwise specified, shall be considered “for reference only”. Any part of this Standard Practice may be quoted. Credit lines should read Extracted from MSS SP-133-2010 with permission of the publisher, Manufacturers Standardization Soc
10、iety of the Valves and Fittings Industry, Inc. Reproduction is prohibited under copyright convention unless written permission is granted by Manufacturers Standardization Society of the Valve and Fittings Industry Inc. Originally Approved: October 2004 Originally Published: December 2004 Current Edi
11、tion Approved: May 2010 Current Edition Published: September 2010 Copyright , 2004, 2010 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.A.MSS STANDARD PRACTICE SP-133ii TABLE OF CONTENTS SECTION PAGE PURPOSE . 1 1 SCOPE 1 2 CONSTRUCTION . 1 3 PERFORM
12、ANCE . 3 4 MANUFACTURING AND PRODUCTION TESTS 8 ANNEX A Referenced Standards and Applicable Dates . 9 MSS STANDARD PRACTICE SP-1331 PURPOSE To provide a Standard Practice for Excess Flow Valves installed in low pressure fuel gas piping systems which are designed to protect the appliance and its conn
13、ections to the piping system by reducing the flow of gas should the flow in the line exceed some predetermined level. 1.0 SCOPE This Standard Practice applies to Excess Flow Valves used with gas fired appliances in Fuel Gas Distribution Systems with operating pressures between 5 inches water column
14、(5”w.c.) and 14 inches water column (14”w.c.). 2.0 CONSTRUCTION 2.1 Definitions Body The principal structure of the device, which contains and supports an actuation mechanism and constitutes the main gas passage. Btu Abbreviation for British Thermal Unit. The quantity of heat required to raise the t
15、emperature of one (1) pound of water 1F. Burner A device for the final conveyance of the gas, or a mixture of gas and air, to the combustion zone. Bypass A passage, provided in the body of the device or in a gas line around the body, which permits a gas flow from the inlet to the outlet connections
16、of the device entirely independent of the action of the valve. Liquefied Petroleum Gases The term “Liquefied Petroleum Gases” and “LPG” as used in this Standard Practice shall mean and include any material composed predominantly of any of the following hydrocarbons, or mixtures of them; propane, pro
17、pylene, butanes (normal butanes or isobutane), and butylenes. Orifice The opening in a cap, spud, or other device whereby the flow of gas is limited and through which the gas is discharged to the burner. Specific Gravity As applied to gas, specific gravity is the ratio of the weight of a given volum
18、e of a gas to that of the same volume of air, both measured under the same conditions. Tools, Special Tools that are not available on the open retail market. 2.2 General 2.2.1 Valve devices covered by this Standard Practice shall automatically limit the downstream flow of gas in the event: 1) That t
19、here is damage to or failure of any part of the house indoor gas piping or gas appliance system downstream of the valve device that would cause a leak to occur exceeding the valve devices rated activation range; or 2) For any other reason that the fuel gas flow exceeds the rated activation range. 2.
20、2.2 This Standard Practice applies to valves for use with natural, manufactured and mixed gases, liquefied petroleum (LP) gases, and LP gas-air mixtures at pressures from 5 inches water column (”w.c.) to 14”w.c. 2.2.3 This Standard Practice applies to excess flow valves not intended for field applia
21、nces and not exceeding 1 inch Nominal Pipe Size (NPS 1). An excess flow valve may be an individual valve or may be incorporated as part of a manually operated gas valve or other such device that includes other means to control main burner gas. Component(s) of such a device shall comply with the appl
22、icable industry standard. In the case where such standards have conflicting EXCESS FLOW VALVES FOR LOW PRESSURE FUEL GAS APPLIANCES MSS STANDARD PRACTICE SP-1332 requirements, the requirements of this Standard Practice shall take precedence. 2.2.4 Valve devices shall be capable of operation at indoo
23、r ambient temperature ranging from 32F to 125F. Valves shall also be capable of operation at temperatures outside this range when so specified by the manufacturer. 2.2.5 Valves shall be constructed entirely of new unused parts and materials. 2.2.6 Compliance with this Standard Practice does not impl
24、y that the valve is acceptable for use on any particular gas appliance or for any particular application without supplemental tests with the valve applied to the particular appliance or application. 2.2.7 If a valve for measurement as given in this Standard Practice is followed by an equivalent valu
25、e in other units, the worst stated value is to be regarded as the specification. 2.2.8 All references to inches water column (”w.c.) throughout this Standard Practice are to be considered gauge pressures, unless otherwise specified. 2.2.9 The intent of this Standard Practice is to be in harmony with
26、 the requirements for fuel gas systems per the National Fuel Gas Code, ANSI Z223.1 (NFPA 54) and the Liquefied Petroleum Gas Code, NFPA 58; and for devices regulated by the American National Standard for Connectors for Gas Appliances, ANSI/CSA Z21.24; the American National Standard for Manually Oper
27、ated Gas Valves for Appliances, Appliance Connector Valves and Hose End Valves, ANSI/CSA Z21.15; and U.S. Requirements for Excess Flow Valves, IAS 3-92. 2.2.10 The construction of parts not covered by this Standard Practice shall be in accordance with reasonable concepts of safety, substantiality, a
28、nd durability. 2.2.11 All specifications as to construction, set forth herein, may be satisfied by the construction actually prescribed or such other construction as will provide at least equivalent performance. 2.2.12 Pins, stems, or other linkages passing through the valve body shall be sealed to
29、provide gas tight construction. 2.2.13 Valves shall be constructed with mechanical means that will prevent gas flow in excess of the manufacturers specified maximum flow rate at maximum inlet operating pressure, at standard conditions. 2.2.14 The valve shall incorporate automatic reset features that
30、 shall permit reset only when designed to do so. 2.3 Equipment and Data to be Furnished by the Manufacturer 2.3.1 The manufacturer shall furnish the following equipment and data when required: a) Representative valves, as specified by the testing agency; b) Drawings, blueprints, and photographs whic
31、h describe each model valve as specified by the testing agency; c) Minimum and maximum operating pressure in inches water column (”w.c.) (see Section 2.2.2); d) Maximum Flow Capacity (see Section 3.4); e) Mounting orientation(s) (see Section 3.1.1). 2.4 Assembly 2.4.1 Valves shall be constructed to
32、discourage disassembly in the field. 2.4.2 Parts of the valve coming in contact with a diaphragm shall not have sharp edges that might chafe or abrade it. 2.4.3 Springs shall be protected against abrasion and shall be guided or arranged to minimize binding, buckling, or other interference with their
33、 free movement. MSS STANDARD PRACTICE SP-1333 2.5 Connections 2.5.1 When pipe threads are used, connections shall be provided with cleanly cut taper pipe threads in accordance with ASME B1.20.1. 2.5.2 A valve equipped with pipe or tubing threads shall be designed to accept a wrench for use in genera
34、l assembly and disassembly to piping. 2.5.3 Inlet and outlet gas connections shall be designed so that when a pipe, which is threaded two threads beyond standard (for the size in question), is run into the threaded portion of the valve body, will not adversely affect the operation of the valve. 2.5.
35、4 Connections for attachment to semi-rigid tubing shall be in accordance with or be interchangeable with the fittings described in SAE J512 or SAE J514, as applicable. 2.6 Bolts, Nuts, and Screws 2.6.1 Bolts, nuts, machine screws, and other threaded parts used in covers, housings, casings, and exter
36、nal mounting brackets shall have threads conforming to, as applicable, ASME B1.1, ISO 68, or ISO 261. 2.7 Materials 2.7.1 Materials used in the manufacture of an Excess Flow Valve shall be those compatible with the applicable fuel gas and suitable for the intended purpose. 2.7.2 Valve bodies or cast
37、ings shall be of material having a melting point of not less than 800F. 2.8 Instructions 2.8.1 The manufacturer shall furnish complete instructions covering installation and proper operation. Included in these instructions shall be: a) Manufacturers or dealers name and address; b) Model number; c) M
38、aximum and minimum operating temperatures (see Section 2.2.4); d) Maximum and minimum operating pressure rating in inches water column (“w.c.) or pound-force per square inch gauge (psig) (see Section 2.2.2); e) The type(s) of gas for which the valve is intended; f) Maximum Btu/hr capacity (see Secti
39、on 3.4); g) Mounting orientation(s) (see Section 3.1.1). 2.9 Marking 2.9.1 Excess flow gas valves shall bear a marking on which appears the following: a) Manufacturers or dealers name, trademark, or symbol; b) Model designation; c) A marking stating “Excess Flow Gas Valve”; d) Direction of gas flow
40、and mounting position(s); e) Maximum Btu/hr capacity (see Section 3.4); f) Symbol of the organization performing the tests for compliance with these requirements; g) Each valve shall bear a date code marking that identifies, at minimum, the month and year of manufacture. 3.0 PERFORMANCE 3.1 General
41、3.1.1 The tests specified herein shall be conducted with the valve mounted in the manufacturers specified position(s). If one or more of the following optional mounting orientations are selected by the manufacturer, additional tests, as specified under Section 3.5, shall be conducted: a) Horizontal
42、Parallel to the horizon; MSS STANDARD PRACTICE SP-1334 b) Vertical Perpendicular to the horizon; c) Multi-poise any position on a horizontal, vertical, or intermediate axis. 3.1.2 Unless otherwise specified, the tests specified herein shall be conducted at operating ambient temperatures of 32F and 1
43、25F or at the limits of the manufacturers specified temperature range. 3.1.3 The tests of Section 3.3 shall be conducted on each sample prior to the tests in Section 3.4. 3.2 Test Gases Unless otherwise specified herein, either natural or LP gas or air may be used for the tests. 3.3 Strength and Def
44、ormation 3.3.1 Pressure All parts of a valve subjected to gas pressure, except a diaphragm, shall withstand a static pressure of 5 psig or the maximum permissible under the National Fuel Gas Code ANSI Z223.1 (NFPA 54). Method of Test Pressure The inlet and outlet of the valve under test shall be con
45、nected to a suitable hydraulic or pneumatic system under room temperature conditions (77F +/- 10F). The pressure shall be raised slowly to 5 psig and held at that pressure for one (1) minute. For a diaphragm type valve, the diaphragm shall be substantially removed to allow the test media to flow fre
46、ely throughout the device body. There shall be no sign of rupture or mechanical dislocation of parts of the enclosure communicating with the atmosphere. 3.3.2 Torque A valve shall be capable of withstanding (without deformation impairing valve operation, breakage, or leakage) the turning effort show
47、n in Table 1 exerted by assembling to piping or tubing. This test shall not apply to valves having flange connections. TABLE 1 Turning Effort for Torque Test Nominal Outlet Connections Size, Inches Turning Effort, Inch-Pounds 1/8170 1/42203/8280 1/23753/4560 1 750Method of Test Torque This test shal
48、l be conducted at room temperature (77F +/- 10F). A wrench of suitable size shall be used to apply the turning force. SAE 10 viscosity machine oil shall be applied to the taper threads of steel pipe nipples, which shall be inserted in the inlet and outlet of the valve and turned up hand tight. With
49、the inlet nipple secured in a vise, the specified turning effort shall be applied to the outlet nipple. For other than straight through type valves, the tests shall be repeated as outlined above, except with the outlet nipple inserted in the vise and the turning effort applied to the inlet nipple. Valves designed for tubing connections shall be tested as outlined above except that the torque shall be applied at opposite ends of the valve body through wrench flats or bosses and not to the tubing fittings. There shall be no evidence of deformati
