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1、FOR INTERNAL UL OR CSDS USE ONLY NOT FOR OUTSIDE DISTRIBUTION Subject 842 January 26, 2007 SUMMARY OF TOPICS The following is being proposed: 1. Reaffirmation and Continuance of the Eighth Edition of the Standard for Valves for Flammable Fluids, UL 842, as an American National Standard, with no chan
2、ges to current requirements. STP BALLOTS AND ALL COMMENTS DUE: MARCH 12, 2007 1. Reaffirmation and Continuance of the Eighth Edition of the Standard for Valves for Flammable Fluids, UL 842, as an American National Standard, with no changes to current requirements. RATIONALE Proposal submitted by: Ed
3、gar Wolff-Klammer, Underwriters Laboratories Inc. Underwriters Laboratories Inc. is proposing to administratively update the ANSI approval of the Standard for Valves for Flammable Fluids, UL 842. The status of an ANSI recognized standard is required to be updated within 5 years of ANSI approval, if
4、the standard has not otherwise been updated on a continuous maintenance program, or if an extension of ANSI recognition of the standard has not otherwise been granted. The latest ANSI approval date for UL 842 is August 3, 1999. At ULs request, ANSI has granted an extension to the status of UL 842 as
5、 an ANSI recognized standard to August 3, 2009. UL is seeking only to maintain the currently published requirements in UL 842 as an American National Standard, and no revisions are proposed at this time. PROPOSAL Standard for Valves for Flammable Fluids, UL 842, Eighth Edition INTRODUCTION 1 Scope 1
6、.1 These requirements cover valves that are intended to be used for the control of fl ammable fl uids. They are of the type commonly used in piping systems and in the assembly of motor fuel dispensing and fuel burning equipment. Valves covered by this standard are for use with fl ammable fl uids whi
7、ch are handled at temperatures within the range of minus 29C (minus 20F) to 52C (125F). 1.2 These requirements cover valves of the manually operated, pressure operated, or temperature operated types, or combinations of such to the exclusion of types operated wholly or partially by electricity. When
8、they form a part of an assembly which provides for additional functions or service, the requirements are outside the scope of these requirements. FOR INTERNAL UL OR CSDS USE ONLY NOT FOR OUTSIDE DISTRIBUTION 1.3 These requirements do not cover the following: a) Valves for handling liquids under cryo
9、genic conditions. b) Valves for general refi nery service, offshore and pipe line terminals, natural gas processing plants, gas distribution systems, petrochemical processing facilities, or the like. c) Constant-level oil valves and electrically operated valves. d) Relief valves and pressure regulat
10、ors for liquefi ed petroleum gas (LP-Gas) service. e) Shutoff and check valves for liquefi ed petroleum gas (LP-Gas) in the liquid phase. f) Manually operated gas valves of the plug and body or rotating disc type which are evaluated under the Standard for Manually Operated Gas Valves for Appliances,
11、 Appliance Connector Valves and Hose End Valves, ANSI Z21.15. g) Valves covered by the Standard for Gas Appliance Pressure Regulators, ANSI Z21.18; the Standard for Automatic Valves for Gas Appliances, ANSI Z21.21; or the Standard for Gas Appliance Thermostats, ANSI Z21.23. 1.4 A product that contai
12、ns features, characteristics, components, materials, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fi re or of electric shock or injury to persons shall be evaluated using appropriate additional component and end-product requirements
13、 to maintain the level of safety as originally anticipated by the intent of this standard. A product whose features, characteristics, components, materials, or systems confl ict with specifi c requirements or provisions of this standard does not comply with this standard. Revision of requirements sh
14、all be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this standard. 2 Glossary 2.1 EMERGENCY SHUTOFF VALVES Valves intended for installation at the inlet of remote control type fl ammable liquid dispensing devices. They are normally he
15、ld open by a mechanical holding means. They incorporate a fusible element and close automatically in the event of exposure to fi re or break-off resulting from severe impact. They are designed for an operating pressure of not less than 50 psi (345 kPa). 2.2 FLAMMABLE FLUIDS Fuel oil, gasoline, keros
16、ene, and similar petroleum products, liquefi ed petroleum gas (LP-Gas) in the gaseous phase, not in excess of 1 pound per square inch (psi) (6.9 kPa), and manufactured and natural fuel gases. 2.3 FUSIBLE LINK VALVES Valves intended for use in lines conveying fuel gas or fuel oil which function to cl
17、ose when the temperature in the vicinity of the valve exceeds the fusing temperature of the fusible element. 2.4 HOSE NOZZLE VALVES Self-closing type valves designed for an operating pressure of minimum 50 psi (345 kPa) and intended for use at the outlet end of a hose for dispensing fl ammable liqui
18、ds. JANUARY 26, 2007SUBJECT 842-2- FOR INTERNAL UL OR CSDS USE ONLY NOT FOR OUTSIDE DISTRIBUTION 2.5 AUTOMATIC HOSE NOZZLE VALVE A hose nozzle valve that incorporates a mechanism that shuts off the fl ow of liquid during refueling operations to prevent overfl ow from the fi ll opening when the tank
19、is overfi lled. 2.5 added October 13, 1997 3 General 3.1 Components 3.1.1 Except as indicated in 3.1.2, a component of a product covered by this standard shall comply with the requirements for that component. 3.1.2 A component is not required to comply with a specifi c requirement that: a) Involves
20、a feature or characteristic not required in the application of the component in the product covered by this standard, or b) Is superseded by a requirement in this standard. 3.1.3 A component shall be used in accordance with its rating established for the intended conditions of use. 3.1.4 Specifi c c
21、omponents are incomplete in construction features or restricted in performance capabilities. Such components are intended for use only under limited conditions, such as certain temperatures not exceeding specifi ed limits, and shall be used only under those specifi c conditions. 3.2 Units of measure
22、ment 3.2.1 When a value for measurement is followed by a value in other units in parentheses, the fi rst stated value is the requirement. 3.3 Undated references 3.3.1 Any undated reference to a code or standard appearing in the requirements of this standard shall be interpreted as referring to the l
23、atest edition of that code or standard. JANUARY 26, 2007SUBJECT 842-3- FOR INTERNAL UL OR CSDS USE ONLY NOT FOR OUTSIDE DISTRIBUTION CONSTRUCTION 4 Assembly 4.1 All valves 4.1.1 A valve shall include all of the components required for its intended function and installation. 4.1.2 When a valve requir
24、es the use of special pipe fl anges, gaskets, bolts, or other special fi ttings or parts for making an installation, such parts shall be furnished by the manufacturer with each valve. 4.1.3 Two or more subassemblies intended to be assembled in the fi eld as a unit shall be capable of being joined to
25、gether without requiring any of the subassemblies to be cut, drilled, welded or otherwise altered. 4.1.4 When two or more valves or actuating devices, or both, are to be used together as one unit, the entire assembly is, for the purpose of these requirements, to be considered and tested as one valve
26、. 4.1.5 The construction of a valve shall be such that parts can be reassembled after being dismantled to the extent provided for routine maintenance. 4.1.6 Means shall be provided for the purpose of making any required fi eld adjustment. 4.1.7 A seat disc shall be attached to its poppet or holder o
27、r otherwise assembled so as to prevent it from becoming dislocated under service conditions as determined by the Endurance Test, Section 21. The means to secure the disc shall not rely upon cement or adhesive. 4.1.8 A brazing material used for joining liquid confi ning parts of a valve shall have a
28、melting point (solidus temperature) of minimum 538C (1000F). 4.1.9 A valve with socket or butt weld ends shall be capable of being installed without damaging nonmetallic seats or seals. Required instructions for accomplishing this shall accompany each valve. 4.2 Shutoff valves 4.2.1 A shutoff valve
29、shall not be equipped with a bypass or with a means to prevent it from closing completely. 4.2.2 The requirement in 4.2.1 does not apply to a feature provided to permit a take-off to recirculate fl uid or to supply a pilot or other individually controlled outlet. 4.2.3 The appropriate operating posi
30、tions or the direction of movement shall be clearly indicated for a manual operating lever or reset handle included in a nonself-closing type valve. 4.2.4 An automatic shutoff valve shall function as a shutoff regardless of the position of any damper or external operating lever or any reset device.
31、The manipulation of a manual-reset device shall not cause the valve to function as an automatic-reset valve. JANUARY 26, 2007SUBJECT 842-4- FOR INTERNAL UL OR CSDS USE ONLY NOT FOR OUTSIDE DISTRIBUTION 4.2.5 An automatic shutoff valve shall not be equipped with means for manually latching the valve
32、in the open position in a manner which prevents the valve from functioning as a shutoff. 4.2.6 An automatic shutoff mechanism shall be guarded to prevent interference with the intended operation of the mechanism. 4.2.7 When a mechanically actuated indicator is provided to show whether the main valve
33、 is open or shut, it shall be visible from a distance of at least 5 feet (1.52 m). 4.2.8 An automatic shutoff valve shall close independently of the energy supplied by the medium fl owing. The medium fl owing is not prohibited from being used to exert supplementary forces on the valve seat. 4.2.9 An
34、 automatic shutoff valve shall close upon accidental escape of the actuating media. 4.3 Hose nozzle valves 4.3.1 A hose nozzle valve shall be of the manually-operated or of the automatic type. A manually-operated valve requires the valve to be manually held open during the entire fi lling operation
35、without the aid of hold-open devices or latches, but is capable of closing automatically. An automatic valve requires the valve to: a) Be manually opened, but is capable of being held open during the fi lling operation by a latch or other device and b) Is provided with automatic closing features. 4.
36、3.2 A hose nozzle valve shall be of the normally closed type. It shall be self-closing upon the manual or automatic release of the operating lever. 4.3.3 A guard shall be provided to guide or protect the free end of an operating lever and to prevent opening of the valve or damage to an operating par
37、t if the valve is dropped. A guard shall be of such strength as to permit operation of the valve subsequent to its being subjected to mechanical strength tests. See the Hose Nozzle Valve Strength Test, Section 15. 4.3.4 An operating lever shall possess the strength required to resist bending or brea
38、king when tested in accordance with these requirements. See the Endurance Test, Section 21. 4.3.5 The closing action of a hose nozzle valve shall be in the direction of fl uid fl ow. A seat seal or valve disc shall consist of resilient material and shall provide proper seating of a disc. 4.3.6 A hos
39、e nozzle valve shall be equipped with a spout not exceeding 12 inches (305 mm) in length. Nozzles shall be of corrosion resistant material, such as brass or aluminum. 4.3.7 A sand casting employed as a pressure confi ning part of a hose nozzle valve shall have a wall thickness of minimum 0.094 inch
40、(2.38 mm). JANUARY 26, 2007SUBJECT 842-5- FOR INTERNAL UL OR CSDS USE ONLY NOT FOR OUTSIDE DISTRIBUTION 4.3.8 A fl exible metal spout shall be fi tted with a threaded adapter that overlaps an end at least 3/4 inch (19.1 mm) for attachment to the body of a valve. The discharge end of a fl exible meta
41、l spout shall terminate in a smooth ferrule. 4.3.9 The means for attaching a spout to a valve body shall permit ready replacement of a spout in the fi eld with the use of ordinary hand tools. 4.3.9 revised October 13, 1997 4.3.10 A hose nozzle valve shall provide electrical continuity from the spout
42、 to the body inlet so that when in use, continuity is provided for grounding of static charges. Such continuity shall be inherent in the construction and shall not be accomplished by a jumper wire. See the Electrical Continuity Test, Section 23. 4.3.11 A hose nozzle valve intended for use in salt wa
43、ter marine or boat yard environments shall be constructed so as to comply with the applicable construction and performance requirements except that the tests specifi ed in Sections 15, 16, 20, 22, and 23 are to be conducted following exposure to a salt enriched atmosphere as described in 24.2 24.6.
44、Exception:A hose nozzle valve is not required to operate in accordance with the requirements of Section 16 when, due to accumulation of salt in the sensing port, the hose nozzle valve does not operate to deliver fl uid. 4.3.12 A hose nozzle valve for use in salt water or boat yard environments shall
45、 be of the automatic closing type without a latch-open device. 4.3.12 added October 13, 1997 5 Materials 5.1 Fluid-confi ning or operating parts of a valve, when failure of the part allows leakage or impairs operation, shall have the strength and durability to provide reliable service of the parts a
46、nd of the assembly. 5.2 To conform to 5.1, a material other than a valve disc or soft seat, a seal ring, a diaphragm, or a gasket shall have a melting point (solidus temperature) of minimum 510C (950F) and a tensile strength of minimum 10,000 psi (69 MPa) at 204C (400F). 5.3 A material not in confor
47、mance with 5.2 is not prohibited from being employed in a hose nozzle valve used only in dispensing service. 5.4 A part in contact with the fl uid to be handled shall be resistant to the action of such fl uid. 5.5 A part made of an elastomer shall not crack or show visible evidence of deterioration
48、following exposure in an air oven for 70 hours at 100C 2C (212F 3.6F). 5.5 revised October 13, 1997 5.6 When atmospheric corrosion of a part interferes with the intended function of a valve, the part shall be of a corrosion resistant material or be provided with a corrosion resistant coating. JANUAR
49、Y 26, 2007SUBJECT 842-6- FOR INTERNAL UL OR CSDS USE ONLY NOT FOR OUTSIDE DISTRIBUTION 5.7 A coating complying with 5.6 shall provide resistance against corrosion to a degree not less than that provided by the coatings specifi ed in 5.8. 5.8 Cadmium plating shall be minimum 0.0003 inch (0.008 mm) thick and zinc plating shall be minimum 0.0005 inch (0.013 mm) thick other than on parts where threads constitute the major portion of the area, in which case the thickness of the cadmium or zinc plating shall be minimum 0.00015 inch (0.0038 mm). 5.9 A hose n
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