1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULMarch 26, 2013Prior to the third issue, the requirements for products covered by this Outlinewere included in the first and second issues of the Outline of Investigation forOxygen-Fuel Gas Combin
2、ation Flash Arrester and Back-Pressure Check Valves.1UL 1357OUTLINE OF INVESTIGATIONFOROXYGEN-FUEL GAS FLASH ARRESTER AND COMBINATION FLASHARRESTER AND BACK-PRESSURE CHECK VALVESIssue Number: 6March 26, 2013Summary of TopicsThis sixth issue of the Outline of Investigation for Oxygen-Fuel Gas FlashAr
3、rester and Combination Flash Arrester and Back-Pressure Check Valvesincludes a revision to the Moist Ammonia-Air Stress Cracking Test.COPYRIGHT 2013 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULMARCH 26, 2013UL
4、 13572No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSINTRODUCTION1 Scope .42 Limitations of Use .43 Glossary .5CONSTRUCTION4 General 5PERFORMANCE5 General 66 External Leakage Test 77 Seat Leakage Test .88 Back Pres
5、sure Check Valve Endurance Test .89 Pressure Activated Shutoff Valve Operation Test .810 Hydrostatic Pressure Strength Test 911 Moist Ammonia-Air Stress Cracking Test .912 Fuel Gas Compatibility Test .1013 Oxygen Compatibility Test 1014 Continuous Flame Test .1115 Flashback Cycling Test 1116 Explosi
6、on Test .1117 Accelerated Aging Test .1318 Heat Sensitive Device Operation Test 1319 Start-To-Discharge/Resealing Pressure Test .14MANUFACTURING AND PRODUCTION TESTS20 General 14MARKING21 General 15MARCH 26, 2013 UL 1357 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION
7、 WITHOUT PERMISSION FROM ULINTRODUCTION1 Scope1.1 These requirements cover combination liquid and dry-type flashback arresters and combinationflashback arresters with back-pressure check valves for use with oxygen and fuel gas consumingequipment.1.2 Devices covered by these requirements are intended
8、 for use in supply piping, regulator outlets, ortorch inlets in accordance with the following standards:a) Standard for the Design and Installation of Oxygen-Fuel Gas Systems for Welding, Cuttingand Allied Processes, NFPA 51 andb) Safety in Welding and Cutting and Allied Processes, AWS Z49.1.2 Limit
9、ations of Use2.1 The maximum service pressure rating of a device for acetylene shall be 15 psig.2.2 The maximum service pressure rating of a device for oxygen and fuel gases other than acetyleneshall be specified by the manufacturer.2.3 The largest size (ID) of hose or pipe intended for use with the
10、 device shall be specified by themanufacturer and piping representing this maximum size shall be used for the Flashback Cycling Test andExplosion Test, Sections 15 and 16, respectively.2.4 If the device is for limited use such as a maximum number of flashbacks (such as 5 or less) or a shortlength of
11、 time (such as 12 months or less), these limitations shall be stated in the manufacturersinstructions provided with each device. In this case, the Flashback Cycling Test, Section 15, is notconducted.2.5 If a device is to be marked with the term Fuel Gas and not the specific fuel gas(es), the device
12、shallbe suitable for all gases specified in 3.3. The maximum service pressure for these gases, other thanacetylene, shall be the same.2.6 Installation instructions shall be provided with each device.MARCH 26, 2013UL 13574UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION
13、WITHOUT PERMISSION FROM UL3 Glossary3.1 For the purpose of this outline, the following definitions apply.3.2 COMPRESSED GAS IN SOLUTION (ACETYLENE) A nonliquefied compressed gas that isdissolved in a solvent.3.3 FUEL GAS Acetylene, hydrogen, natural gas, liquefied petroleum gas (LP-Gas),methylacetyl
14、ene-propadiene stabilized gas (MPS-Gas), natural gas, methane and propylene.3.4 LIQUEFIED COMPRESSED GAS A gas which under the charged pressure is partially liquid at atemperature of 70.0F (21.1C).3.5 MPS-GAS Methylacetylene-propadiene, stabilized; a mixture of gases that, in the liquid phaseconform
15、s to the following:a) Methylace-propadiene (in combination, with a maximum ratio of 3.0 moles ofmethylacetylene per mole of propadiene in the initial liquid phase in a storage container) 68mole percent maximum;b) Propane, butane, isobutane (in combination) 24 mole percent minimum of which at least1/
16、3 (8 mole percent of total mixture) shall be butane and/or isobutane;c) Propylene 10 mole percent maximum; andd) Butadiene 2 mole percent maximum.CONSTRUCTION4 General4.1 A device shall include all of the components necessary for its intended function and installation andshall be furnished as a sing
17、le unit or assembly.4.2 A seat disc shall be attached to its poppet or holder, or otherwise assembled to prevent it frombecoming dislocated under service conditions. The means to secure the disc shall not rely on cement oradhesive.4.3 A brazing material used for joining liquid-confining parts of a d
18、evice shall have a melting point (solidustemperature) not less than 1000F (538C).4.4 A part in contact with the gas to be handled shall be resistant to the action of such gas.4.5 If corrosion of a part will interfere with the intended function of the device the part shall be of acorrosion-resistant
19、material or be provided with a corrosion-resistant protective coating.MARCH 26, 2013 UL 1357 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL4.6 A protective coating shall provide resistance against corrosion to a degree not less than that pr
20、ovidedby the protective coatings specified in 4.7.4.7 Cadmium plating shall have a thickness of not less than 0.0003 inch (0.008 mm), and zinc platingshall have a thickness of not less than 0.0005 inch (0.013 mm).Exception: If threads constitute the major portion of the area of a part, the thickness
21、 of the cadmium orzinc plating may not be less than 0.00015 inch (0.0038 mm).4.8 A part made of drawn brass or machined from brass rod incorporating female threads made of copperalloy containing more than 15 percent zinc shall be subjected to the 10-Day Moist Ammonia-Air StressCracking Test, Section
22、 11.4.9 Copper or a copper alloy exceeding 67 percent copper shall not be used for a part in contact withacetylene or MPS-Gas.4.10 If the device is for use with regulators, torches, or hose assemblies, its inlet and outlet connectionshall be threaded and conform to Standard Connections for Regulator
23、 Outlets, Torches and Fitted Hosefor Welding and Cutting Equipment, CGA Pamphlet E-l; right hand threads for oxygen, left hand threadsfor fuel gases.4.11 Other threaded connections may be used if the threads conform to a nationally recognized standardand the device is intended for such application.4
24、.12 A device shall not terminate in a hose barb type of connection.PERFORMANCE5 General5.1 A device may be investigated for oxygen or fuel gases. This outline anticipates the fuel gases outlinedin 3.3. Representative samples of either the fuel gas or oxygen model may be used for the required tests,i
25、f the construction is identical except for the threaded connections. For most tests the maximum ratedworking pressure is used to determine test pressure. Because the oxygen pressure rating is always higherthan the fuel gas rating, it is therefore used to determine test pressure, except for the Conti
26、nuous Flame,Flashback Cycling, and Explosion Tests, Sections 14 16 respectively.5.2 To determine the test pressure and fuel gas(es) to be used for the Explosion Test, Section 16, seeTable 5.1.MARCH 26, 2013UL 13576UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT
27、 PERMISSION FROM ULTable 5.1Test gasesFuel gas at maximum working pressure Test fuel gases and pressureAcetylene at 15 psig Acetylene at 20 psigFuel gases as defined in 3.3 at 25 psig maximum Acetylene at 20 psigAcetylene at 15 psig and all other fuel gases as specified bymanufacturer (includes hydr
28、ogen)Acetylene at 20 psig and hydrogen at 1.2 times maximumworking pressureAcetylene at 15 psig and other fuel gas(es) does not includehydrogen as specified by the manufacturerAcetylene at 20 psig and propane at 1.2 times maximumworking pressureOne fuel gas as specified by the manufacturer 1.2 times
29、 maximum working pressure of the specific fuel gas5.3 When acetylene is used for the Explosion Test, Section 16, 11 trials shall be conducted with theacetylene-oxygen mixture varying for each trial as follows: 6.5% 15.5% and 35% acetylene by volumein 1% increments. When hydrogen is used, 10 trials s
30、hall be conducted, with the mixture varying asfollows: 20% 29% hydrogen by volume in 1% increments. When propane is used, 10 trials shall beconducted with the mixture varying as follows: 3.0% 10%, and 15% and 29% propane by volume in 1%increments.5.4 For the Continuous Flame Test, Section 14, if the
31、 device is for use with acetylene and other fuelgases, the test is conducted with acetylene and hydrogen. If the device is for use with acetylene and otherfuel gases other than hydrogen, the test is conducted with acetylene and propane. If the device is for useonly with one fuel gas, the test is to
32、be conducted with that gas.5.5 For the Flashback Cycling Test, Section 15, if the maximum working pressure of the fuel gases is 50psig or less either one of the test fuel gases used in the Explosion Test is to be used. If the maximumworking pressure of the fuel gases is greater than 50 psig, hydroge
33、n or the specific fuel gas at 1.2 timesmaximum rated pressure shall be used. Stoichiometric mixture of oxygen and fuel gas shall be used;Acetylene 35% by volume, Hydrogen 67% by volume, Propane 29% by volume. See Table 5.1.6 External Leakage Test6.1 Three representative samples are subjected to this
34、 test. Aerostatic pressure of 1-1/2 times themaximum rated pressure is applied through the inlet with the outlet sealed. The pressure is applied in thenormal flow direction for 1 minute. No visible external leakage at any body joints is allowed.MARCH 26, 2013 UL 1357 7UL COPYRIGHTED MATERIAL NOT AUT
35、HORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL7 Seat Leakage Test7.1 The same samples subjected to the External Leakage Test, Section 6, are used for this test.Aerostatic pressure from 1/4 psig to 1-1/2 times the maximum rated pressure is applied at the outlet ofthe valve
36、 with the inlet open. This pressure is applied in the back flow direction for 1 minute. No visibleleakage is allowed past the seat.8 Back Pressure Check Valve Endurance Test8.1 One representative sample of each type of back pressure check valve shall be subjected to 50,000cycles of operation at a ra
37、te not faster than 10 cycles per minute. Aerostatic pressure sufficient to allowflow through the sample is applied in the flow direction and then quickly reduced to 0 psig pressure andwhile 100 psig pressure is applied in the backflow direction.8.2 If the device incorporates a pressure activated shu
38、toff valve that prevents flow in either direction, thenumber of cycles is reduced to 100 and the pressure for the endurance test is a pressure just belowactivation pressure of the shutoff valve.8.3 If the device incorporates a hose coupler, the socket portion shall be subjected to the devicesmaximum
39、 rated pressure (static condition) and the mating plug, which is plugged, shall be inserted andremoved for 50,000 cycles. If provided with a locking means, it may be defeated for this test.8.4 The samples that have undergone the endurance test are again subjected to the seat and externalleakage test
40、s noted above after the endurance test is completed. No external or seat leakage is allowedafter completion of the cycling.9 Pressure Activated Shutoff Valve Operation Test9.1 This test is conducted if such a device is incorporated into the assembly. One sample, that has beensubjected to the Seat Le
41、akage Test, Section 7, shall be subjected to this test. The outlet of the sampleshall be subjected to increasing aerostatic pressure until the shutoff valve actuates. This pressure shallbe recorded. The valve mechanism shall then be cycled for 100 cycles, (6 cpm) in the following manner.Aerostatic p
42、ressure of 5 psig above the pressure that caused actuation shall be applied to the outlet ofthe valve and then released. The device shall then be reset. The application of pressure is to be repeated.At the conclusion of this cycling, aerostatic pressure of 1-1/2 times maximum working pressure shall
43、befirst applied to the outlet and the device checked for seat leakage at the inlet, and then the test pressureshall be applied to the inlet and the device checked for seat leakage at the outlet. The device shall thenbe tested again to determine activation pressure. This pressure shall not have signi
44、ficantly changed afterthe cycling.MARCH 26, 2013UL 13578UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL10 Hydrostatic Pressure Strength Test10.1 Representative samples will be subjected to the maximum pressure developed in the ExplosionTest,
45、Section 16, if measured. If the explosion pressure is not measured, 2500 psig shall be used. Thebody of the device shall not rupture or be permanently deformed after such test. The hydrostatic pressureshall be applied through the inlet with the outlet sealed. The pressure shall be maintained for 1 m
46、in.11 Moist Ammonia-Air Stress Cracking Test11.1 After being subjected to the conditions described in 11.2 11.3, a pressure confining brass partcontaining more than 15 percent zinc shall:a) Show no evidence of cracking, delamination, or degradation orb) Perform as intended when tested as described i
47、n 11.5.11.2 One test sample of each size is to be subjected to the physical stresses normally imposed on orwithin a part as the result of assembly with other components. Samples with female tapered pipe threads,intended to be used for installing the product in the field are to have the threads engag
48、ed and tightenedto the required torque. Samples with female threads other than tapered pipe threads shall be torqued asspecified by the manufacturer. Teflon tape or pipe compound is not to be used on any threads. Sampleswith male threads are evaluated in “as received” condition.11.3 The samples are
49、then to be tested in accordance with Apparatus (Section 6), Reagents andMaterials (Section 7), Test Media (Section 8), Test Sample Preparation (9.3 9.4), and Test Procedure(10.1 10.4) of the Standard Test Method for Ammonia Vapor Test for Determining Susceptibility toStress Corrosion Cracking in Copper Alloys, ASTM B858-06, with the test solution pH level High 10.50.1; exposure temperature of 25 1C; and with the examination in accordance with 11.4.11.4 After the exposure period, the samples are to be examined for cracks or other signs
