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Ordering Information 3 .1 Orders for fire hose under this specifi-cation should include the following informa-tion: 3.1.1 ASTM designation, 3.1.2 Different jacket fibers, if required see
AMERICAN NATIONAL ANSI/ASTM D 296 - n Reproduced By GLOBAL STANDARD ENGINEERING DOCUMENTS With The Permlsalon Of ASTM Under Royalty Agreement AMERICAN SOCIETY FOR TESTING AND MATERIALS 1916 Race St., Philadelphia, Pa 19103 Reprinted from the Annual Book of ASTM Standards, Copyright ASTM If not listed in the current combined index, will appear in the next edition Standard Specification for RUBBER-LINED FIRE HOSE WITH WOVEN JACKET1 This Stand3!d is issued under the fixed design~~on D 296; the num~r_i~mediately foll~wing the designation indicates the year of ong1Dal adoption or, ID the case of reV1s1on, the year of last rev1S1on A number ID parentheses indicates the year of last reapproval · 1 Scope larities of twist as is consistent with good man- ufacturing practice If agreed between the 1.1 This specification applies to the trade manufacturer and the purchaser at the time of sizes of 38-mm (l'h-in.), 51-mm (2-in.), and the order, the jackets may be made in whole 64-mm (2 112-in.) single-jacket and 38-mm or in part of fibers other than cotton suitable (1 1/2-in.), 51-mm (2-in.), 64-mm (2½-in.), for assuring satisfactory service life 76-mm (3-in.), and 89-mm (3 1/2-in.) multiple- jacket, rubber-lined fire hose suitable for use 4.2 Each jacket shall be seamless and shall in public or private fire departments Single- have the fillers woven around the hose jacket hose may be provided with a protective throughout its length and the warps inter- cover Hoses will be hydrostatically pressure- woven with and substantially covering the fill- tested with couplings attached but the cou- ers The jackets may be separate or inter- plings or method of attachment are not cov- woven ered by this standard S Rubber Lining 2 Applicable Documents 5 1 The lining shall be made of a properly 2.1 ASTM Standards: vulcanized rubber compound which will com- D 412 Tests for Rubber Properties in Ten- ply with all tests specified in Sections 6 to 8, inclusive It shall be made from either calen- sion2 dered sheets, lap-jointed and vulcanized in D 572 Test for Rubber Deterim:ation by one solid body, or from a single-ply extruded tube Heat and Oxygen Pressure3 · D 3183 Rubber-Preparation of Pieces for 5.2 The waterway surface of the lining shall be smooth and partically free from pit- Test from Other Than Standard Vulcan- ting and other imperfections and from corru- ized Sheets2 gations 3 Ordering Information 5.3 The lining shall be of uniform thickness and within the limits of thickness, exclusive of 3.1 Orders for fire hose under this specifi- backing, shown in Table 1 cation should include the following informa- tion: 5.4 Backing- The backing, if used, shall not exceed 0.71 mm (0.028 in.) in thickness, 3.1.1 ASTM designation, as measured from the bottom of the corruga- 3.1.2 Different jacket fibers, if required tions It need not be of the same composition (see 4.1), as the rubber lining, but the adhesion between 3.1.3 Conditions and location regarding hydrostatic pressure test (see 9 1), ' This specification is under the jurisdiction of ASTM 3.1.4 Hose diameter size required (see Committee D-11 on Rubber and Rubber-Like Materials 12.1), and and is the direct responsibility of Subcommittee D 11.31 on 3.1.5 Length required (see 13.1) Rubber Hose 4 Woven Jacket Current edition approved March 25, 1977 Published May 1977 Originally published as D 296-28 T Last pre- 4.1 The jackets shall be well, evenly, and vious edition D 296-76 firmly made from good cotton free from un- sightly defects, dirt, knots, lumps, and irregu- • Annual Book of ASTM Srandards, Pans 35 and 37 3 Annual Book of ASTM Standards, Part 37 ~m~ D 296 : : : J1:' - static pressure of 2.1 MPa (300 psi) for 5 s without leaking, or breaking any thread in the the backing and the jacket shall conform to jacket Each length of multiple-jacketed hose the requirements specified in Section 8 shall withstand a hydrostatic pressure of 2 8 MPa (400 psi) for 5 s without leaking or 6 Tensile Properties of Lining breaking any thread in the jackets 6 1 The tensile strength of specimens taken 9.3 Elongation -The elongation of the from the rubber lining shall not be less than hose under 2.1 MPa (300 psi) hydrostatic 8.3 MPa (1200 psi) pressure for single-jacketed, and 2.8 MPa (400 psi) for multiple-jacketed, shall not ex- 6.2 Elongation at Rupture -The ultimate ceed 10 % of the length for single-jacketed elongation, when rupture occurs in the tensile hose and 8 % of the length for multiple- strength test, shall not be less than 400 % 51 jacketed hose, from an initial measurement to 255 mm (2 to 10 in.) taken at a pressure of 69 kPa (10 psi) 6.3 Permanent Elongation -The perma- 9.4 Twist-The hose, under 2.1 MPa (300 nent elongation (or set) of specimens cut psi) hydrostatic pressure for single-jacketed, transversely from the lining, elongated from and 2.8 MPa (400 psi) for multiple-jacketed, 51 to 204 mm (2 to 8 in.), held for 2 min, shall not twist more than indicated in Table 1 released, and measured 2 min after release These measurements shall be based on an shall not exceed 25 % original position established under a hydro- static pressure of 69 kPa (10 psi) The figures 7 Accelerated Aging Test in Table 2 refer to the final twist in a direction to tighten, rather than loosen, the couplings 7 1 The tensile strength and ultimate elon- A twist to the right (in the direction that gation of specimens of the rubber lining that would tend to tighten the couplings) is indi- have been subjected to the action of oxygen at cated by a clockwise rotation of the free end a pressure of 2100 ± 69 kPa (300 ± 10 psi) of the hose, viewing from the supply end A and a temperature of 70 ± 2°C (158 ± 3.6°F) maximum twist to the left of 6 6 deg/m (2 deg/ for a period of 96 h shall be not less than 60 % ft) will be permitted while pressure is being of the tensile strength and ultimate elongation raised, and any final twist shall be to the right of similar specimens that have not been heated in oxygen 9.5 Warp and Rise-The hose, under 2.1- MPa (300-psi) hydrostatic pressure for single- 8 Adhesion Test of Lining jacketed, and 2.8 MPa (400 psi) for multiple- jacketed, shall not warp more than 510 mm 8.1 The adhesion between the lining and (20 in.) from a straight line drawn from center the cotton jacket shall be such that the rate of to center of the findings on the ends of the separation of a 38-mm (1 ½-in.) strip of lining hose No rise from the level of the test table from the jacket shall be not greater than 25 shall be permitted for multiple-jacketed hose mm (1 in.)/min under a weight of 5.4 kg (12 Single-jacketed hose shall not rise from the lb) level of the test table more than that indicated in Table 3 These measurements shall be 8.2 This requirement is not intended to ex- based on an original position established un- clude a construction that provides no adhesion der a hydrostatic pressure of 69 kPa (10 psi) between the jacket and lining along the fold, if the surface over which there is no adhesion is 10 Bursting Strength Test not greater than 35 % of the total surface 10.1 A 1-m, (3-ft) sample of the hose, 9 Hydrostatic Pressure Tests while lying either straight or curved to a radius of 69 cm (27 in.), shall withstand without 9.1 All hydrostatic pressure tests shall be failure a hydrostatic pressure as indicated in performed either at the factory or at the desti- Table 4 nation, at the discretion of the purchaser Ar- rangements for such tests shall be subject to 11 Kink Test agreement between manufacturer and the 11.1 A full length of the hose, while purchaser at the time the order is placed If desired, the manufacturer may humidify the kinked, shall withstand without rupturing or hose for hydrostatic tests 9.2 Proof Pressure Test-Each length of single-jacketed hose shall withstand a hydro- 2 D 296 breaking any thread in the jackets a hydro- 16.3 One length of hose shall be selected at static pressure as indicated in Table 5 random from every 760 m (2500 ft), or frac- tion thereof, for the kink test specified in 12 Diameter Section 11 12 1 The hose shall have an internal diam- 16.4 A sample, 1 m (3 ft) in length, shall eter of not less than the trade size of the hose, be taken from every 1520 m (5000 ft) of hose, except that for 64-mm (2 1/i-in.) hose the in- or fraction thereof, for the bursting strength ternal diameter shall be not less than 65 mm test specified in Section 10 (2 9/i6 in.) TEST METHODS 13 Length 17 Lining Thickness 13.1 Unless otherwise specified, the hose shall be in nominal lengths of 15.2 m (50 ft) 17 1 Apparatus: No nominal 15.2-m (50-ft) length shall be less 17.1.1 Dial Micrometer, graduated to than 14.6 m (48 ft) before sampling Length 0.025 mm (0.001 in.) and having a presser measurements shall be made from back end to foot 6.3 ± 0.25 mm (0.25 ± 0.01 in.) in back end of the couplings, with the hose under diameter, exerting under dead load a total 69-kPa (IO-psi) hydrostatic pressure force of (0.84 ± 0.03 N) (3 ± 0.1 ozf) (7 1.2 Buffing Machine in accordance with 14 Workmanship Recommended Fractice D 3183 17 1.3 Metal Die, conforming to Die A re- 14.1 The character of the workmanship quirements of Methods D 412 shall be such as is incident to good manufac- 17 2 Procedure: turing practice 17 2 1 Separate the lining of vulcanized rubber or unmilled natural rubber latex from 15 Marking the jacket without the use of solvent, if prac- ticable, and without excessive stretching of 15 1 Beginning at a point not less than 1 2 the rubber If it is necessary to use a solvent, m (4 ft) from each end, each 15 2-m (50 ft) use a commercial isooctane, benzene, or simi- length of hose shall be stenciled at two places lar low-boiling petroleum solvent which, upon in indelible letters at least 25 mm (1 in.) in evaporation, will not leave an oily residue height with the name of the manufacturer, or Make the separation gradually while gripping other identification acceptable to the pur- the lining near the point of separation Then chaser, and the month and year of manufac- place the lining so as to permit free evapora- ture tion from all parts of the surface and allow to rest at least 1 h before measuring 16 Sampling 17 2 2 Take the thickness on two 12 5-mm ( 1h-in.) die-cut specimens cut from the ring 16.1 Each length of hose shall be examined sample, selected so that the specimens include and tested for the following items: opposite folds in their constricted portions Buff the constricted portions of these die-cut 16.1.1 Weaving of jackets, specimens just sufficiently to remove the fab- 16.1.2 Construction of lining, ric impressions left by the jacket The speci- 16 1.3 Smoothness of waterway, mens may be buffered by hand, if desired 16.1.4 Workmanship, After buffing, take three measurements on 16.1.5 Length, each specimen in the area from which the 16 1.6 Hydrostatic proof pressure, fabric impressions have been removed, using 16.1.7 Elongation, twist, warp, and rise, the dial micrometer specified in 17 1 1 Take and the average of six measurements as the lining 16.1.8 Marking thickness 16.2 A sample not less than 200 mm (8 in.) 17 2 3 Separate the linings of latex-coated in length shall be taken from each lot of 380 m fabric from the jacket without the use of sol- (1250 ft) or fraction thereof of hose, for the vent as specified in 17 2 1 and measure the tests specified in Sections 5 3, 6, 7, 8, and 12 All test specimens shall be cut transversely from the sample whenever possible 3 D 296 total thickness of fabric and coating as speci- 19 Physical Tests fied in 17 2.2, except omit buffing of the spec- imens Then carefully separate the latex coat- 19 1 Apparatus: ing from the fabric and measure the thickness 19 1.1 Testing Machine - Tension tests of the coating as specified in 17 2.2, except shall be made on a power-driven machine omit buffing of the specimens equipped with a suitable dynamometer and indicating or recording device for measuring 18 Lining Adhesion the applied force within ± 2 % (Note 1) If the capacity range cannot be changed during a 18 1 Apparatus - The apparatus required test, as in the case of the pendulum dynamom- for this method consists of a supporting frame, eter, the applied force at break shall be mea- clamps, weights, weight holders, and a timer sured within ± 2 % , and the smallest tensile The supporting frame shall be of such design force measured shall be accurate to within that specimens, with weights attached, may be 10 % If the dynamometer is of the compen- suspended vertically and hang freely during sating type for measuring tensile stress di- the progress of the test rectly, means shall be provided to adjust for the cross-sectional area of the specimen The 18.2 Procedure: response of either an indicator or recorder 18.2.1 Cut the adhesion test specimens all shall be sufficiently rapid that the applied transversely from the samples in rings 50 mm force is measured with the requisite accuracy (2 in.) in width Then open these rings and lay during the extension of the specimen to rup- them out flat so as to give rectangular speci- ture If the tester is not equipped with a re- mens of length equal to the full circumference corder, a device shall be provided that indi- of the hose Accurately cut on each specimen cates after rupture the maximum force applied a central strip of lining 38 mm (1 ½ in.) in during extension Testers equipped with a de- width, the cut extending through the lining vice to measure elongation automatically shall but not entirely through the woven jacket be capable of determining extensions within Separate these strips from the jacket at one 5 % of the original length If elongation is end for a distance of about 38 mm measured manually, a scale capable of meas- 18.2.2 With the separated jacket gripped uring each 10 % elongation shall be provided in a stationary clamp, grip the separated rub- ber in a freely suspended clamp hanging verti- Norn 1-An accuracy of 2 % does not permit cally, to which the prescribed weight is at- the use of the portion of the range below 50 times tached with suitable provision for supporting the smallest change in force that can be measured and releasing it slowly without jerking Note In machines with close graduations the smallest the dista·nce through which separation takes change in force that can be measured may be the place for a period of 10 min, or until complete value of a graduation interval; with open gradua- separation occurs Take the adhesion to the tions, or with magnifiers for reading, it may be an jacket as the rate obtained by dividing the estimated fraction, rarely as fine as one tenth of a total distance separated in centimetres (or graduation interval; and with verniers it is custom- inches) (to the nearest 2.54 mm (0.1 in.)), by arily the difference between the scale and vernier the elapsed time in minutes graduations measured in terms of scale units If the 18 2 3 If a rubber backing is used between indicating mechanism includes a stepped detent, the the lining and the jacket, determine the adhe- detent action may determine the smallest change in sion between the lining and the backing and force detectable the adhesion between the backing and the jacket, using 18.1 to 18.2.2 If the adhesion 19 1.2 Grips - The tester shall have two between the lining and the backing or be- grips, one of which shall be connected to the tween the backing and the jacket cannot be dynamometer, and a mechanism for separat- determined because the backing has a ten- ing the grips at a uniform rate of 8.3 ± 0.8 dency to tear during the test, consider the rate mm/s (20 ± 2 in./min) (Note 2) for a distance of separation between separating members as of at least 750 mm (30 in.) Grips for testing the adhesion dumbbell specimens shall tighten automati- cally and exert a uniform pressure across the gripping surface, increasing as the tension in- creases in order to prevent uneven slipping and to favor failure of the specimen in its 4 D 296 constricted section At the end of each grip a break in the curved portion just outside the positioning device is recommended for insert- gage marks may be accepted if within the ing specimens to the same depth in the grip minimum requirements and aligning them with the direction of pull 19 2 2 Calculation: NoTE 2-A rate of separation of 17 mm/s (40 in./ 19.2.2.1 Calculate the tensile strength as min) may be used in routine work and notation of follows: the speed used made on the report, but in casi: of dispute the rate shall be 8.3 :!: 0.8 mm/s (20 :!: 2 m./ Tensile strength, MPa(psi) = FIA min) where: 19.2 Tensile Strength and Elongation: F observed force to break the specimen, 19.2.1 Procedure-Cut dumbbell speci- mens transversely from the sample using Die and A of Methods D 412 Buff specimens oflining A cross-sectional area of the unstretched to remove uneveness of surface, such as jacket depressions or corrugations, and to remove specimen backing, if used, which would interfere with 19 2 2 2 Calculate the elongation as fol- an accurate measurement of the specimen lows: thickness Buff the samples prior to cutting out with the die Make three measurements Elongation,% = ((L - L 0 )/L0 ] x 100 for thickness in the constricted portion of the specimen Use the minimum value obtained where: as the thickness of the specimen in calculating L observed distance between the bench the tensile strength Place two parallel gage marks for use in determining elongation sym- marks on the stretched specimen, and metrically 50 mm (2 in.) apart on the con- L0 original distance between the bench stricted portion perpendicular to the longitu- dinal axis of the specimen The marks should marks be narrow as consistent with good visibility 19 3 Permanent Elongation - Determine Marks made with ink, using a stamp with the permanent elongation (or set) on speci- parallel steel blades, are recommended Take mens cut transversely from the lining, elon- care not to injure the lining Make measure- gated to 75 % of the required ultimate elon- ments of tensile strength and elongation on gation, held for 2 min, released, and mea- the same specimen Place the test specimen in sured 2 min after release the clamps, using care to adjust it symmetri- 19 4 Accelerated Aging - Prepare three cally in order that the tension is distributed specimens taken from the lining in the same uniformly over the cross section If the tension manner as for physical tests, except for stamp- is greater on one side of the test specimen ing the 50-mm (2-in.) marks before placing than on the other, the gage marks will not the samples in the aging vessel Then age the remain parallel and the maximum strength of specimens for 96 hat 70 :!: 2°C (158 :!: 3.6°F) the rubber will not be developed Start the in accordance with Method D 572 machine and run until the specimen ruptures Note and record the elongation and breaking 20 Rubber Cover load Elongation is the increase in distance between the gage marks at rupture Tensile 20.1 Procedure - When single-jacketed strength is the breaking load in newtons hose is supplied with a protective rubber cov- (pounds-force) divided by the product of the ering, perform tests on the cover for thick- minimum thickness and width of the con- ness, tensile, elongation, adhesion, set, and stricted portion When a dumbbell test speci- aging as spelled out for the lining men breaks outside the gage marks, or if the result of either tensile strength or elongation 21 Hydrostatic Pressure Tests is below the requirements, test an additional specimen, and consider the results as final 21.1 Due to the inherent danger to person- However, results of tests of specimens that nel in conducting tests at high pressures on fire hose, only well-qualified personnel shall perform the following testing under proper conditions It is strongly recommended that they be performed at the factory or an inde- pendent test laboratory equipped to perform the required tests Before testing, the hose may be humidified by the manufacturer 5 D 296 21.2 Proof Pressure: necessary to complete the measurements and 21.2 1 Apparatus - Hydrostatic pressure observations To expedite the test program, a may be applied by means of a hand or power- "nominal length" may be assumed unless the driven pump or an accumulator system capa- actual length measured at 70 kPa (10 psi) is ble of increasing the pressure in the hose at a less than 14.6 m (48 ft) or more than 16.1 m rate not less than 2 1 MPa (300 psi) nor more (53 ft) than 7.0 MPa (1000 psi)/min A test table, or equivalent, may be used to provide a clear 21.3 Elongation - For hose that does not space of at least 500 mm (20 in.) wide on each warp to any extent, take the measurement side of a line drawn through the center of the parallel to the edge of the test table For this water supply connection parallel to the edges purpose, mark off an edge of the table in of the test table and equipped with properly metres and millimetres (or feet and inches) calibrated pressure gages A slight incline up- When the hose warps to any appreciable ex- ward from point of supply is desired to facili- tent and particularly when the allowable limit tate in removing air when filling the hose of elongation is approached, measure the 21.2.2 Procedure: length at final pressure by following the con- 21 2.2.1 Connect one end of the length to tour of the hose Take all measurements from the supply and fill with water Elevate the the inside edges of the fittings opposite end during the filling period to allow all air to escape through a petcock before 21.4 Twist - The amount of twist can be applying pressure This is important as a measured by following the color line or by safety measure because expansion of air com- noting, during the period during which the pressed in the hose, when suddenly released pressure is being applied, the turns of the by bursting or other failure, might result in a fittings at the free end of the hose Record the serious accident Then close the petcock and amount of twist to the nearest one-eighth turn raise the pressure to 70 kPa (IO psi) and hold or 45 deg Report the direction of twist as there while the initial length measurement is right or left A right twist is in the direction taken While at this pressure, straighten out that would tend to tighten couplings the hose in order to obtain accurate measure- ment Measure the length of hose between 21.5 Warp- Warping is the deviation from fittings and record to the nearest 10 mm (or 1 a straight line drawn from fitting to fitting in a in.) Note the position of the hose with regard plane parallel to the surface on which the hose to twist From this point on, neither the hose rests For hose having nominal length of 15 m nor the fittings are to be touched, moved, or (50 ft), the amount of warping is the maxi- interfered with in any way until all measure- mum deviation of any portion of the hose ments and observations have been completed from a straight line drawn from center to cen- at the final test pressure ter of the fittings For hose having nominal 21.2 2.2 During the time the hose is being length greater than 15 m (50 ft) and up to 30 prepared for this test, note and record the m (100 ft), the amount of warping is the jacket construction and workmanship in maximum deviation of any 15-m (50-ft) por- weaving, particularly the matter of knots, tion of the hose from an initial straight line loose ends, and skips in warp threads drawn from the center of the fittings at each 21 2 2 3 Following measurement of length end of the hose The warp is measured as the at 70 kPa (10 psi), increase the pressure in the distance from the referenced straight line to hose at a rate of not less than 2 1 MPa (300 the center line of the hose at the point of psi) nor more than 7 0 MPa (1000 psi)/min maximum deviation As an alternative until the required test pressure is reached method, when desired by the manufacturer, While the pressure is being increased carefully the position of the hose relative to the water examine the hose for leakage and other de- supply may be reversed, end for end, follow- fects Maintain the test pressure for at least 15 ing the first measurement of warping, and the s, but not more than 1 min The time during test for warping then repeated which the test pressure is maintained should not exceed the minimum of 15 s longer than is 21.6 Rise - Consider the amount that the hose rises from the surface of the test table as "rise", and record as such Report results to the nearest 10 mm (or¼ in.) 21.7 Kink: 6 D 296 21 7 1 Apparatus - The apparatus shall be water supply, expel the air, and raise the pres- the same as in 21.2.1 sure at a rate of not less than 2 1 MPa (300 psi) nor more than 7.0 MPa (1000 psi)/min 21 7 2 Procedure - Conduct this test on a until the hose bursts The sample may be full length of hose Fill the hose with water tested straight or curved to a radius of 690 with the petcock open to allow all air to es- mm (27 in.) Where more than one sample is cape Then close the petcock, raise the pres- to be tested, perform the test alternately, sure to approximately (but not exceeding 70 straight and curved kPa (10 psi), and kink the hose 45 cm (18 in.) from the free end by tying the hose back 21 9 Diameter: against itself as close to the fitting as practica- 21.9.1 Apparatus-A tapered plug gage of ble, so that there will be a sharp kink Then wood or metal having a taper of 31 mm/m {3/s raise the pressure at a rate of not less than 2 1 in./ft), marked to indicate variations of 1.5 MPa (300 psi) nor more than 7 0 MPa (1000 mm (1164 in.) in diameter and provided with a psi)/min to the required pressure and immedi- slot 16 mm (5/s in.) wide by 2.3 mm {3/n in.) ately release deep to accommodate the lap joint of the hose lining 21.8 Burst: 21.9.2 Procedure-Cut the end of the hose 21.8 1 Apparatus - The apparatus shall be square and insert the tapered plug gage in the similar to that for 21.2 1, except that instead hose sample until a close fit is obtained with- of the test table, a suitable enclosure shall be out forcing Record the diameter of the gage used to protect the operator at the end of the sample, to the nearest 1.5 21.8 2 Procedure -Cut a 1-m (3-ft) sample mm {1/64 in.) as the internal diameter of the from a length selected at random before the hose length is subjected to the hydrostatic proof test Connect the sample to the source of TABLE 1 Requirements for Lining Thickness TABLE 3 Rise of Single Jacket Hose Internal Diameter of Hose Lining Thickness, Size of Hose, Single Jacket Permissible Rise, min max mm in mm in mm in mm in 38, 51, and 64 JI/,, 2 and 21/, 1.24 0.049 38 and 51 11/, and 2 180 7 76 3 1.47 0.058 64 89 3 1/ i 1.83 0.072 211, 100 4 TABLE 2 Twist Requirements for Hose Trade Size of Hose Twist, max Jackets mm in deg/m deg/ft 38 and 51 I 112 and 2 single 164 50 64 2½ single 82 25 38 and 51 I½ and 2 multiple 95 29 64, 76, and 89 2 ½, 3, and 3 \/2 multiple 40 12 7 ~m~ D 296 TABLE 4 Burst Pressure or Hose Sample Trace Size Required Pressure mm in Number or Jackets MPa psi 38 51 and 64 I'"· 2, and 211, single 3.5 500 38 51 64 76 and 89 multiple 11,,,-2 2 ,,;, 3 and 3 'n 4.2 600 TABLE 5 Bursi Pressure or Kinked Hose Trade Size Required Pressure in Number of Jackets MPa psi m 38, 51 and 64 I'"· 2." and 1 single 2.1 300 38, 51, and 64 multiple 76 and 89 2 11 multiple 11,, 2 and 2 111 2.5 350 3 and 3 1,, 1.8 250 The American Society for Testing and Materials takes no position respecting the validity ofany patent rights asserted in connection with any item mentioned in this standard Users of this standard are expressly advised that determination ofthe validity ofany such patent rights, and the risk ofinfringement of such rights, is entirely their own responsibility 8