1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULDecember 27, 20061SUBJECT 1785OUTLINE OF INVESTIGATIONFORLP-GAS FUEL HOSE AND HOSE ASSEMBLIES FOR VEHICLE ENGINESIssue Number: 5DECEMBER 27, 2006Summary of TopicsThis new issue of SU 1785 is bein
2、g issued through ULs electronicpublishing system to ensure format uniformity between the PDF andHTML versions of the document. No substantive changes have beenincorporated in the document.The UL Foreword is no longer located within the UL Standard. For informationconcerning the use and application o
3、f the requirements contained in thisStandard, the current version of the UL Foreword is located onULStandardsInfoNet at: http:/ 2006 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULDECEMBER 27, 2006SUBJECT 17852No
4、 Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSGENERAL1 Scope .52 Units of Measurement .5CONSTRUCTION3 Internal Diameter .54 Tube and Cover 65 Thickness of Tube or Cover 66 Reinforcement 67 Couplings 7PERFORMANCE8 Ge
5、neral 79 Proof-Pressure Test .79.1 General .79.2 Samples .79.3 Equipment .79.4 Method 710 Leakage and Coupling Retention 810.1 General 810.2 Sample 810.3 Equipment 810.4 Method .811 Hydrostatic-Strength Test .811.1 General 811.2 Sample 911.3 Equipment 911.4 Method .912 Adhesion Test .912.1 General 9
6、12.2 Sample 912.3 Equipment 912.4 Method .1013 Pull Test .1013.1 General .1013.2 Sample .1013.3 Equipment .1013.4 Method .1014 Tensile Strength and Elongation Tests of Tube and Cover .1114.1 General .1114.2 Samples 1114.3 Equipment .1114.4 Method .1215 Accelerated Aging Tests .1215.1 General .1215.2
7、 Samples 1315.3 Equipment .13DECEMBER 27, 2006 SUBJECT 1785 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL15.4 Method .1316 Flexibility Test 1416.1 General .1416.2 Sample .1416.3 Equipment .1416.4 Method .1417 Permeability Test .1517.1 Gene
8、ral .1517.2 Samples 1517.3 Equipment .1517.4 Method .1518 Low-Temperature Test 1518.1 General .1518.2 Samples 1518.3 Equipment .1518.4 Method .1619 Ozone-Exposure Test .1619.1 General .1619.2 Samples 1619.3 Equipment .1619.4 Method .1620 Immersion Test on Tube and Cover .1720.1 General .1720.2 Sampl
9、es 1720.3 Equipment .1720.4 Method .1821 Salt-Spray Corrosion Test .1921.1 General .1921.2 Samples 1921.3 Equipment .1921.4 Method .1922 10-Day Moist Ammonia-Air Stress Cracking Test .19MANUFACTURING AND PRODUCTION TESTS23 General 20DECEMBER 27, 2006SUBJECT 17854UL COPYRIGHTED MATERIAL NOT AUTHORIZE
10、D FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULGENERAL1 Scope1.1 These requirements cover hose and coupled hose assemblies in sizes up to and including a nominalinternal diameter of 5/8 inch (15.9 mm) for conveying liquefied petroleum gas (LP-Gas) as a fuel forinternal combustio
11、n engines on vehicles, covered by 3-6.2.1 of the Standard for the Storage and Handlingof Liquefied Petroleum Gases, NFPA 58. The hose or assembly is to be used and installed in accordancewith 3-6.2.5(d) and 3-6.2.8 of NFPA 58.1.2 The hose or assembly is intended for a maximum working pressure of 350
12、 psig (2400 kPa) and foruse at temperatures within the range of minus 40 to plus 176F (minus 40 to plus 80C).1.3 A product that contains features, characteristics, components, materials, or systems new or differentfrom those covered by the requirements in this outline, and that involves a risk of fi
13、re, electric shock, orinjury to persons shall be evaluated using the appropriate additional component and end-productrequirements as determined necessary to maintain the acceptable level of safety as originally anticipatedby the intent of this outline. A product whose features, characteristics, comp
14、onents, materials, or systemsconflict with specific requirements or provisions of this outline cannot be judged to comply with this outline.Where considered appropriate, revision of requirements shall be proposed and adopted in conformancewith the methods employed for development, revision, and impl
15、ementation of this outline.2 Units of Measurement2.1 If a value for measurement is followed by a value in other units in parentheses, the second value maybe only approximate. The first stated value is the requirement.CONSTRUCTION3 Internal Diameter3.1 The internal diameter of a hose shall be equal t
16、o the nominal size 1/32 inch (0.8 mm), as determinedby the method described in 3.2 and 3.3.3.2 A tapered plug gauge of wood or metal having a taper of 3/8 inch per foot (31.3 mm/m) marked toindicate variation of 1/64 inch (0.4 mm) in diameter, a set of wood or metal plug gauges, straight or balltype
17、, in increments of 0.005 inch (0.13 mm), or in some cases, see 3.3, an expanding ball gauge andmicrometer or other equivalent means to accurately measure the expanded ball, is to be used.3.3 The end of the hose is to be cut square. If a tapered plug gauge is used, the plug gauge is to beinserted in
18、the hose sample until a close fit is obtained without forcing. The diameter of the gauge at theend of the sample, to the nearest 1/64 inch (0.4 mm), is to be recorded as the internal diameter of thehose. If a set of straight or ball-type plug gauges is used, the diameter of the gauge, which when ins
19、ertedin the hose sample gives a close fit without forcing, is to be recorded as the internal diameter of the hose.If the end of a hose is constricted or flared, the inside diameter is to be measured far enough from theend to be representative of the inside diameter by means of an expanding ball gaug
20、e.DECEMBER 27, 2006 SUBJECT 1785 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL4 Tube and Cover4.1 A tube or a cover shall be smooth, of uniform thickness, free from defects in workmanship, and freefrom pitting, blisters, or other imperfect
21、ions. Intentional pricking of a cover shall not be considered animperfection. This requirement is not intended to exclude the use of a corrugated cover.5 Thickness of Tube or Cover5.1 The thickness of a tube and a cover shall be not less than 0.047 inch (1.19 mm).5.2 A power-driven buffing machine (
22、grinding wheel) is necessary for buffing off irregularities inspecimens. The abrasive wheel is to be No. 30 to 36 grit; and the diameter and rotary velocity of the wheelare to be such that it will have a peripheral speed of 4000 700 feet per minute (20.3 3.6 m/s). Themachine is to be provided with a
23、 slow feed to avoid overheating of the specimen.5.3 A dial micrometer graduated to 0.001 inch (0.025 mm) which exerts a load of 80 85 grams bymeans of a weight is to be used. The load is to be applied through a flat contact foot 0.25 0.01 inch (6.40.25 mm) in diameter.5.4 One piece, about68inches (1
24、50 200 mm) in length, is to be used in determining the thicknessof the lining and cover in accordance with 5.5 and 5.6.5.5 A strip, about68inches (150 200 mm) in length and 1 inch (25.4 mm) in width, or as close to a1-inch width as possible for a small diameter hose, is to be cut from the hose, and
25、the rubber partseparated from the plies. In case the thickness of the part is not uniform around the circumference of thehose, the strip is to be cut from the thinnest portion of the sample.5.6 The strip specimen is to be buffed to remove the impressions left by the fabric or braid or othersurface i
26、rregularities, using the buffing machine described in 5.2. A series of five thickness measurementsare to be taken within the area from which the impressions have been removed, and the maximum readingobtained is to be taken as the thickness of the rubber part.6 Reinforcement6.1 A tightly braided stai
27、nless steel reinforcement with at least 90 percent coverage shall be evenly andfirmly applied over the tube or over a reinforcement of cotton or synthetic fibers firmly applied over thetube. Hose having a reinforcement not complying with the above is permitted if found to be substantiallyequivalent
28、to stainless steel braided hose complying with the requirements of this Outline when subjectedto heat, flame, water, impact, and kinking.DECEMBER 27, 2006SUBJECT 17856UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL7 Couplings7.1 Couplings sha
29、ll be made from brass or from steel with a protective coating. See the Salt-SprayCorrosion Test, Section 21 and the 10-Day Moist Ammonia-Air Stress Cracking Test, Section 22.PERFORMANCE8 General8.1 The following performance tests apply to hose furnished to the purchaser with or without couplingsatta
30、ched, unless indicated otherwise.9 Proof-Pressure Test9.1 General9.1.1 A hose, when lying straight, shall withstand a hydrostatic pressure of 700 psig (4830 kPa) for 5minutes without leakage, ballooning, or rupture.9.2 Samples9.2.1 One 3-foot (0.9-m) length of hose is to be used.9.3 Equipment9.3.1 H
31、ydrostatic pressure may be applied by means of a hand- or power-operated pump or anaccumulator system capable of increasing the pressure in the hose at a rate of approximately 1000 psig(6900 kPa) per minute. All pressures are to be measured with a calibrated pressure gauge.9.4 Method9.4.1 Using coup
32、lings or temporary test fittings, one end of the hose is to be connected to the source ofwater and the other end closed with a fitting provided with a valve for the escape of air while the hose isbeing filled with water. The hose is to be placed on a test table or other flat surface.9.4.2 With the v
33、alve open, the water is to be gradually admitted through the hose until all of the air hasbeen expelled and the hose is completely filled. The valve is then to be closed and the pressure in thehose increased at a uniform rate of approximately 1000 psig (6900 kPa) per minute until the required testpr
34、essure is reached. While the pressure is being increased, the hose is to be carefully examined forleakage and other defects. When the test pressure has been reached, it is to be held at 5 minutes andthe hose checked for leakage or ballooning.DECEMBER 27, 2006 SUBJECT 1785 7UL COPYRIGHTED MATERIAL NO
35、T AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL10 Leakage and Coupling Retention10.1 General10.1.1 A coupled hose assembly shall withstand an aerostatic pressure of 700 psig (4830 kPa) for 10minutes without slippage of the couplings, leakage of the couplings or hose,
36、or damage to the hose at thecouplings.10.2 Sample10.2.1 One 3-foot (0.9-m) length of hose, with couplings attached, is to be used.10.3 Equipment10.3.1 Aerostatic pressure may be applied by means of a source of pressurized air or nitrogen capableof increasing the pressure in the hose at a rate of app
37、roximately 1000 psig (6900 kPa) per minute. Thepressure is to be measured with a calibrated pressure gauge.10.3.2 A protective water-tight enclosure with means for safely observing the sample during the test is tobe used to protect the operator.10.4 Method10.4.1 The coupled hose assembly is to be ma
38、rked prior to the test with a pencil or other suitable deviceat a point immediately adjacent to each coupling. The sample is then to be connected to the source ofaerostatic pressure and placed in the protective enclosure so that the entire sample is immersed in water.The pressure is then to be incre
39、ased at a uniform rate of approximately 1000 psig (6900 kPa) per minuteuntil the required test pressure of 700 psig (4830 kPa) has been reached. The test pressure is to bemaintained for 10 minutes. While the hose assembly is pressurized, it is to be examined for slippage andleakage of the hose and c
40、ouplings and damage to the hose at the couplings.11 Hydrostatic-Strength Test11.1 General11.1.1 A hose shall withstand a hydrostatic pressure of 3500 psig (24,150 kPa) without leakage,ballooning, or rupture.DECEMBER 27, 2006SUBJECT 17858UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION
41、 ORDISTRIBUTION WITHOUT PERMISSION FROM UL11.2 Sample11.2.1 A 3-foot (0.9-m) length of hose is to be used.11.3 Equipment11.3.1 The equipment for this test is to be the same as specified for the proof-pressure test, except that,instead of the test table or surface, an enclosure is to be used to prote
42、ct the operator.11.4 Method11.4.1 The hose sample, while lying straight, is to be connected to the pump and filled with water or otherliquid, leaving the valve open to allow the air to escape. The valve is then to be closed and the pressurein the hose is to be increased at a uniform rate of approxim
43、ately 1000 psig (6900 kPa) per minute untilthe required test pressure of 3500 psig (24,150 kPa) has been reached.12 Adhesion Test12.1 General12.1.1 The rate of separation between the cover and the reinforcement, shall not exceed 1 inch perminute (0.42 mm/s) when tested in accordance with 12.4.1. The
44、 adhesion between wire braids ofreinforcement and between the tube and a wire braid of reinforcement shall be such that adjacent braids,and the tube and the braid, adhere firmly to each other by means of a rubber compound impregnated inthe braids.Exception: This requirement does not apply to the adh
45、esion between the cover or tube and any lightfabric braids embedded in or vulcanized to the cover or tube to the reinforcement.12.2 Sample12.2.1 A short length of hose is to be used.12.3 Equipment12.3.1 Adhesion tests are to be conducted with the type of equipment described for the Standard TestMeth
46、ods for Rubber Property Adhesion to Flexible Substrate, ASTM D413-98.DECEMBER 27, 2006 SUBJECT 1785 9UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL12.4 Method12.4.1 Samples of the hose are to be prepared in accordance with the specifications
47、 for adhesion testsin the Methods of Testing Rubber Hose, ASTM D380-94. Samples of hose are to be prepared using asharp, fine-blade saw. The samples are to be tested in accordance with the procedure for ring samplesusing (1) the Standard Test Methods for Rubber Property Adhesion to a Flexible Substr
48、ate, ASTMD413-98 and (2) a weight of 10 pounds (4.5 kg).12.4.2 If the adhesion of the reinforcement to the cover is such that the parts cannot be separatedsufficiently to permit attachment of the clamp, the adhesion is considered to be in compliance with therequirements.13 Pull Test13.1 General13.1.
49、1 A coupled hose assembly shall withstand a 400-pound (1760-N) pull force.13.2 Sample13.2.1 A 1-foot (0.3-m) coupled length of hose is to be used.13.3 Equipment13.3.1 A power-operated machine, as described in the Standard Test Methods for Vulcanized Rubberand Thermoplastic Rubbers and Thermoplastic Elastomers Tension, ASTM D412-98a, is to be used.The rate of travel of the power-actuated grip is to be 0.5 0.1 inch (12.7 mm) per minute.13.4 Method13.4.1 The couplings on each end of the sample are to be connected
