UL SUBJECT 328-2014 Outline of Investigation for Gasoline Torches (Issue 3)《汽油火炬的调查大纲 (议题3)》.pdf

1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULFebruary 5, 20141UL 328Outline of Investigation for Gasoline TorchesIssue Number: 3February 5, 2014Summary of TopicsThis third issue of the Outline of Investigation for Gasoline Torches, UL328, i

2、ncludes clarification of the scope, removal of requirements for oil,and revisions to the Moist Ammonia-Air Stress Cracking Test.ULs Outlines of Investigation are copyrighted by UL. Neither a printed norelectronic copy of an Outline of Investigation should be altered in any way. All ofULs Outlines of

3、 Investigation and all copyrights, ownerships, and rights regardingthose Outlines of Investigation shall remain the sole and exclusive property of UL.COPYRIGHT 2014 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL

4、FEBRUARY 5, 2014UL 3282No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSINTRODUCTION1 Scope .42 General 42.1 Components .42.2 Units of measurement .52.3 Undated references .5CONSTRUCTION3 Materials .54 Assembly 55 Ho

5、se Connections 56 Venting of Handles 67 Valve Stems 68 Pressure Sensors .69 Flashback Protection 6PERFORMANCE10 Leakage Test 611 Operation Test 712 Start-To-Discharge/Resealing Pressures of Safety Valves 713 Excess Flow Operation Test 814 Hydrostatic Strength Test .915 Valve-Endurance Test .916 Temp

6、erature Test .1017 Accelerated Aging Test 1118 Accelerated Oxygen Pressure Aging Test .1119 Fuel Gas Compatibility 1119.1 General .1119.2 Volume change 1219.3 Weight loss 1220 Moist Ammonia-Air Stress Cracking Test 12MANUFACTURING AND PRODUCTION TESTS21 General .13MARKING22 General 13INSTRUCTIONS23

7、General 13FEBRUARY 5, 2014 UL 328 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINTRODUCTION1 Scope1.1 These requirements cover gasoline torches used in preheating and cutting operations. The termgasoline includes gasoline with small amount

8、s of additives such as detergents, solvents for detergents,and anti-icing chemicals and gasoline with up to 10 percent ethanol.2 General2.1 Components2.1.1 Except as indicated in 2.1.2, a component of a product covered by this outline shall comply with therequirements for that component.2.1.2 A comp

9、onent is not required to comply with a specific requirement that:a) Involves a feature or characteristic not required in the application of the component in theproduct covered by this outline, orb) Is superseded by a requirement in this outline.2.1.3 A component shall be used in accordance with its

10、rating established for the intended conditions ofuse.2.1.4 Specific components are incomplete in construction features or restricted in performancecapabilities. Such components are intended for use only under limited conditions, such as certaintemperatures not exceeding specified limits, and shall b

11、e used only under those specific conditions.2.1.5 A product shall be formed and assembled so that it will have the strength and rigidity necessary toresist the abuses to which it is likely to be subjected, without resulting in a risk of fire or injury to personsdue to total or partial collapse with

12、resulting reduction of spacings, loosening or displacement of parts, orother defects.2.1.6 Hose and hose assemblies for gasoline use shall comply with the applicable sections in theStandard for Hose and Hose Assemblies for Dispensing Flammable Liquids, UL 330.2.1.7 Regulators, when provided, shall c

13、omply with the Standard for Compressed Gas Regulators, UL252.2.1.8 Low pressure gauges, when provided on regulators, shall comply with Standard for CompressedGas Regulator Accessories, UL 252A.2.1.9 High pressure gauges, when provided, shall comply with the Standard for Gauges, IndicatingPressure, f

14、or Compressed Gas Service, UL 404.FEBRUARY 5, 2014UL 3284UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL2.1.10 A pressure vessel, when provided, shall be constructed in accordance with the ASME Boiler andPressure Vessel Code, Section VIII, Ru

15、les for Construction of Pressure Vessels, Division I, and shall bemarked with the pressure vessel symbol.2.1.11 Non-pressurized tanks, when provided, shall comply with the Standard for Metal Safety Cans, UL30.2.2 Units of measurement2.2.1 Values stated without parentheses are the requirement. Values

16、 in parentheses are explanatory orapproximate information.2.3 Undated references2.3.1 Any undated reference to a code or standard appearing in the requirements of this outline shall beinterpreted as referring to the latest edition of that code or standard.CONSTRUCTION3 Materials3.1 Devices of this t

17、ype shall be constructed of materials that are compatible with the gas or gases withwhich they are used. Metal parts shall be inherently corrosion resistant or protected to resist corrosion.4 Assembly4.1 A torch unit consists of a valve body assembly burner tube, orifice(s), and burner head(s). A to

18、rch unitmay also incorporate an integral container assembly that may be refillable.5 Hose Connections5.1 Hose connections shall be union connections, which do not require gaskets. They shall have left-handthreads for the attachment of fuel-gas hose fittings and right-hand threads for oxygen hose fit

19、tings andshall comply with the specifications of the Compressed Gas Association in the Standard Connections forRegulator Outlets, Torches, and Fitted Hose for Welding and Cutting Equipment, E-1.5.2 With reference to 5.1, a slip-joint connection is allowed to be used for connecting hose having aninte

20、rnal diameter of 3/16 inch (4.8 mm) or smaller.FEBRUARY 5, 2014 UL 328 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL6 Venting of Handles6.1 Non-gas-carrying spaces in handles shall be vented.7 Valve Stems7.1 The valve stem of a gas control

21、 valve shall be so constructed that it cannot be removed withoutremoving the packing nut or stem-retaining means.8 Pressure Sensors8.1 Torches shall be provided with a means to prevent continued delivery of fuel to the hose assembly inthe event of hose rupture.8.2 Torches shall be provided with a me

22、ans to prevent the buildup of pressure in the fuel storageassembly if it is exposed to external sources of heat.9 Flashback Protection9.1 Torches shall be provided with flashback protection to prevent explosion of gases or vapor/airmixtures resulting from the flame of the torch igniting fuel in the

23、fuel line and/or fuel tank. This may beaccomplished through the following or equivalent means:a) Designs that keep the fuel in an inert state (e.g. liquid) until the fuel is in the burner head tobe mixed for combustion, for example through suitable pressurization of the fuel to preventbuildup of vap

24、ors andb) Combustion burner head designs that minimize the risk of clogging.PERFORMANCE10 Leakage Test10.1 A torch unit is to be subjected for one minute to an internal aerostatic pressure of not less than 1-1/2times the service pressure specified by the manufacturer. There shall be no observable le

25、akage.10.2 This test is to be conducted on three samples of each torch unit design. For torch units incorporatingan integral container assembly, the container portion is to be provided with a fitting for connection to asource of aerostatic pressure. The samples are to be tested with the shutoff valv

26、e in a closed position sothat seat leakage, as well as external leakage, can be checked.FEBRUARY 5, 2014UL 3286UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL11 Operation Test11.1 Each torch assembly is to be tested in accordance with the man

27、ufacturers instructions and shallperform its intended function.11.2 This test is to be conducted on the same samples subjected to the Leakage Test, Section 10, using:a) Fuel containers filled and charged as intended andb) All equipment comprising the assembly.12 Start-To-Discharge/Resealing Pressure

28、s of Safety Valves12.1 The start-to-discharge pressure of each sample of a safety valve shall be within 3 percent of theaverage of the pressures, but the start-to-discharge pressure of any one of the three samples shall not beless than 100 percent, nor more than 110 percent, of the set pressure mark

29、ed on the valve.12.2 The resealing pressure of a safety valve shall not be less than 90 percent of the initially observedstart-to-discharge pressure.12.3 A safety valve is to be connected to an air- or other aerostatic-supply source capable of beingmaintained at a pressure of at least 50 psi (344 kP

30、a) above the marked set pressure of the valve beingtested. A positive-shutoff valve and a pressure indicating device, are to be installed in the pressure-supplypiping. The pressure gauge is to be installed in the piping between the valve being tested and the shutoffvalve. Start-to-discharge and rese

31、aling pressures are to be observed through a water seal not more than4 inches (101.6 mm) deep. The pressure indicating device shall comply with one of the following:a) An analog gauge having a pressure range such that the test pressure is between 30 and 70percent of the maximum scale reading of the

32、gauge;b) A digital pressure transducer, or other digital gauge, that is calibrated over a range ofpressure that includes the test pressure; orc) Other device that is equivalent to the devices in (a) or (b).12.4 The shutoff valve is to be opened to permit the pressure to the valve being tested to inc

33、rease towithin about 25 psi (172 kPa) of the set pressure marked on the valve. The pressure to the valve is thento be increased slowly, at a rate no greater than 2 psi (13.8 kPa) per second, until the first bubbles throughthe water seal are observed. The pressure at this instant, as indicated by the

34、 pressure gauge, is to berecorded as the start-to-discharge pressure of the valve under test.12.5 After recording the start-to-discharge pressure of the valve, the pressure is to be increased to abovethe start-to-discharge pressure to unseat the valve. The shutoff valve is then to be tightly closed

35、and thewater seal, as well as the pressure gauge, are to be closely observed. The pressure at which bubblesthrough the water seal cease is to be recorded as the resealing pressure of the valve.FEBRUARY 5, 2014 UL 328 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WIT

36、HOUT PERMISSION FROM UL13 Excess Flow Operation Test13.1 An excess flow valve shall operate at no more than 10 percent above, nor less than 20 percentbelow the rated closing flow capacity specified by the manufacturer, and shall close automatically at apressure differential across the valve of no mo

37、re than 15 psi (103 kPa) during the operation testsdescribed in 13.2 13.14.13.2 Three samples of each size and style of valve are to be subjected to these tests. A valve intendedfor use only with liquid is to be tested with water, otherwise the tests are to be made both with air and withwater. Excep

38、t as indicated in 13.3, separate tests are to be run with each sample installed in vertical,horizontal and inverted positions. The tests with air are to be made without piping or other restrictionconnected to the outlet of the test sample.13.3 A valve intended for installation in one position only m

39、ay be tested only in that position.13.4 The test with air is to be conducted by utilizing a properly designed and calibrated orifice flowmeterof the flange type connected to an air supply source of adequate capacity and pressure.13.5 The test sample is to be connected to the outlet of the flowmeter.

40、 A manometer or calibratedpressure indicating device is to be installed on the upstream side of the test sample to indicate the closingpressure. The pressure indicating device shall comply with one of the following:a) An analog gauge reading in increments of no more than 1/2 psi (3 kPa);b) A digital

41、 pressure transducer, or other digital gauge, that is calibrated over a range ofpressure that includes the test pressure; orc) Other device that is equivalent to the devices in (a) or (b).13.6 The test is conducted by slowly increasing the flow of air through the flowmeter until the check valveclose

42、s. At the instant of closing, the pressure differential across the flowmeter orifice and the closingpressure indicated by the gauge are to be recorded. The rate of flow at closing is then to be calculated.13.7 Other types of flowmeters and a gas, other than air, may be used.13.8 The test with water

43、is to be conducted using a liquid flowmeter (or equivalent) installed in a pipingsystem having the pressure to provide the required flow. The system is to include an inlet piezometer orpipe at least one pipe size larger than the valve to be tested, with a flow control valve connected betweenthe flow

44、meter and piezometer. A hose or hydrostatic relief valve, or both, may be used to reduce the effectof the pressure shock when the excess flow valve closes.13.9 The test sample is to be connected to the outlet end of the piezometer. A manometer or pressureindicating device gauge of the retard type, i

45、s to be connected to a pressure takeoff on the upstream sideof the test sample to indicate the closing pressure. The connection is to be made using a length of rubberhose between the pressure gauge and the pressure take-off, with a valve installed at the gauge inlet topermit bleeding air from the sy

46、stem. The pressure indicating device shall comply with one of the following:a) An analog gauge which permits readings in the range of060psi(0414kPa);b) A digital pressure transducer, or other digital gauge, that is calibrated over a range ofpressure that includes the test pressure; orc) Other device

47、 that is equivalent to the devices in (a) or (b).FEBRUARY 5, 2014UL 3288UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL13.10 Prior to the test, the flow control valve is to be opened slightly, with the bleed valve at the pressuregauge open, t

48、o eliminate air from the system. The bleed valve is then to be closed. The test is conductedby slowly increasing the flow until the check valve closes. During the test, the pressure gauge is to bepositioned at the same level as the test sample. At the instant of closing, the rate of flow and closing

49、pressure are to be recorded.13.11 An excess flow valve used in the assembly of a filler valve shall close automatically at a pressuredifferential of no more than 20 psi (138 kPa) when tested as described in 13.12.13.12 Three samples of each size of valve are to be subjected to these tests. The tests are to beconducted with air, and separate tests are to be run with each sample mounted vertically and horizontally.The tests are to be conducted as described in 13.4 13.7, with a filler valve hose coupling connected tothe test sample and with the upper back pressure check val