1、- -, - - hp - - y AECMA PREN2253 BLi m LOL231L 00-02b116 3-a- - * - - prEN2253 A.E.C.M.A. STANDARD NORME A.E.C.M.A. A.E.C.M.A. NORM Edition 1 February 1984 a Ln m A I i I- l 5 ENGLISH VERSION c) u In w 2 a m O O Ln t- !i?- .c $ Flexible hose assemblies in elastomers 2 -Type 1 - Technical Specificati
2、on J Aerospace Series 9 o - O! - O m m I -I 0 a O enlastomres Schlauchleitungen aus Elastomeren w -Type 1 - -Typ 1 - ct ! Srie arospatiale Tuyauteries flexibles Luft- und Raumfahrt !? v Spcification technique . . . Technische Lieferbedingungen -I w 5 2 W O cn CT 3 W 3 L E .E n w z W This industrial
3、standard for the aerospace sector has been drawn up under the responsibility of AECMA (Association Europenne des Constructeurs de Matriel Arospatial). It is published on yelfow paper in three equivalent versions (English, French, German). It will be submitted to CEN (European Committee for Standardi
4、zation) as a draft European Standard. u) W z w 8 3 W z I- U 2 o 8 4 U a t w O w O Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-AECMA PREN2253 8Lt LO
5、I12311 00026117 5 a prEN2253 Page 2 Contents Annex A Annex B Annex C General . Scope and field of application References Definitions, symbols and abbreviations Description of the product Conduct of tests Qualification Acceptance conditions Utilisation tinie Copyright Association Europeene des Constr
6、ucteurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A.E .C.MA. STANDARD prEN2253 * Flexible hose assemblies . in elastomers -Type 1- . Technical specification O General prEN2253 Page 3 For general
7、information concerning the various types of non-metallic flexible hose assemblies see EN2245. 1 This standard specifies the requirements for flexible elastomer hose assemblies type 1 for pressure classes I, I I, I I I, IV and V.intended for use on aircraft to convey fluids. This standard applies whe
8、never it is referenced in a drawing, contact, or other standard. The present standard does not apply to flexible hose assemblies intended for oxygen systems. Scope and field of application 2 References =- IS0 471 - 1977 - Rubber - Standard temperatures, humidities and times for the conditioning and
9、testing of test pieces. EN2245 - Pipelines for liquids and gases - Definitions. EN2379 - Test fluids for non-metallic materials 1 1. 3 Definitions, symbols and abbreviations See EN2245. o 1) In preparation. r 0- Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IH
10、S under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN2253 Page 4 4 Description of the product Each flexible hose assembly consists of a cylindrical hose in elastomer of consta_nt cross section with an end fitting at each end1 l. The hose ma
11、y be armed by means of a layer of fabric or reinforced with steel wire braid and covered in any other manner. 5 Conduct of tests Before being used on aircraft, the flexible hose assemblies must be capable of clearing the following tests : - qualification test specified in clause 6 - acceptance tests
12、 specified in clause 7 All these tests may however be conducted at any time during manufacture or assembly. 6 Qualification 6.1 General Qualification is the recognition of the capability of a manufacturer to manufacture a product in accordance with this Technical Specification and ta guarantee its p
13、roduction at an acceptable quality level. Unless otherwise stated, qualification remains valid as long as no modification is made to the hose assembly. 62 Submission For each nominal size, type and class of flexible hose assembly for which qualification is requested, the manufacturer shall supply th
14、e Official authorities with a certain number of fitted-out hose assemblies of appropriate length, as well as with some bare hose. As regards the quantity and the numbering of test pieces, see the test schedules corresponding to the hose assemblies : - table 4 - class I - table 5 - class II - table 6
15、 - class II I - table 7 - classes IV and V 6.3 External markings The method of marking shall be at the manufacturers discretion, however it must not damage the flexible hose assembly and must be legible for the identification of the hose assembly after testing. 6.3.1 Identification of hose - Manufac
16、turers trade mark and reference - Type, pressure class and/or nominal pressure - Nominal size - Manufacturing batch 1) Attachement by a clip is not permissible, Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduc
17、tion or networking permitted without license from IHS-,-,-AECMA PREN2253 84 -LO12311 OOOZbSO 5 32 40 50 63 - 25,4 31,8 41,3 55,3 prEN2253 Page 5 80 71,2 6.3.2 Jdentification of end fitting - Manufacturers trade mark_ - Nominal size 6.3.3 identification of hose assembly - Manufacturers trade mark and
18、 reference - Type pressure class and/or nominal pressure - Nominal size of hose assembly - Date of assembly and of proof pressure test of the hose assembly 6.4 Tests common to all hose assemblies 6.4.1 Physical checks 6.4.1.1 Examination of product Each hose assembly shall be carefully examined to c
19、heck that it has been correctly made and is free from defects. 6.4.1.2 Minimum passage diameter at the bead This diameter (see figure 1 and table 1) is checked with a gauge of which the end is of spherical form and of which the diameter is equal to the minimum passage diameter with tolerance O, 4,02
20、5 mm. The weight of the gauge shall be equal to 18 times the nominal size in grammes. The gauge shall pass through the hose under its own weight without lubrication. FIGURE l - Minimum passage diameter at the bead ,F at the bead - 5 2P - 6 TABLE 1 Copyright Association Europeene des Constructeurs de
21、 Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,- AECMA PREN2253 84 m LOL2311 O002653 7 = prEN2253 Page 6 6.4.1.3 Variation of length and volume Connect one of the end fittings of the hose assembly to a p
22、ressure source, the other fitting being blanked and left free. The internal volume of the hose assembly shall not vary by more than 15 % under nominal pressure PN applied for 3 to 5 minutes. The length shall remain within the following limits : class I classes I I to V : - 4 % ; + 2 % under pressure
23、 PN One of the procedures used to measure the variations of volume and length is described in Annex A. The two hose assemblies used for this check may be used for any other test. : - 2 % ; + 10 % under test pressure 2 PN 6.4.2 Ageing 6.4.2.1 Ageing in the liquid conveyed This test which appears in t
24、ables 4 to 7 shall be carried out on hose assemblies weighed before testing. As a rule, the liquid used for this test is that for which the hose assembly is intended. When one and the same hose assembly is capable of carrying several kinds of liquid, the Official Authorities will select the fluid or
25、 liquids to be used for the test as shown in the table 2 below. The hose assemblies shall be completely immersed in a tank containing thetest fluid for 7 days at a temperature of 70 +1“C so that they are surrounded on all sides and that there is no air inside the hose. A tank preventing the escape o
26、f volatile matter is used for this test. After being used ten times a new bath of liquid shall be used. TABLE 2 - Products for tests No 1 2 3 4 5 6 - Products used for the tests (examples) Lubricant (see Annex B) Hydraulic fluid, petroleum base (see Annex C) Mixture of 70 % iso-octane and 30 % tolue
27、ne Phosphoric ester hydraulic fluid Hot air Water met hano I 6.4.2.2 Ageing by the gas conveyed As a general rule, the gas used for this test which appears in tables 4 to 7, is that for which the hose assembly is intended. When one and the same hose assembly is capable of carrying several kinds of g
28、as, the Official Authorities select the gas or gases to be used for the test. The hose assemblies are placed for 7 days in a chamber containing the gas held at the temperature of 70 41 OC. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AE
29、CMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,- AECMA PREN2253 84 W 1012311 0002652 7 W prEN2253 Page 7 6.4.2.3 Ageing in air This test is indicated in tables 4 to 7. The hose assemblies are placed for 7 days in a chamber containing air held at the temperature
30、of 70 i 1 OC without any particular hygrometric requirement. 6.4.3 Tests after ageing 6.4.3.1 After ageing by the liquid or gas conveyed 6.4.3.1.1 This test is indicated in tables 4 to 7. The minimum inside diameter of the hose assemblies shall not be less than 90 % of that measured during the dimen
31、sional check (see sub-subclause 6.4.1.2). 6.4.3.1.2 Vacuum test This test indicated in tables 4 to 6 applies only to hose assemblies of classes I, I I and I I I. The empty hose assembly of which one end is blanked and the other connected to a vacuum pump is held bent over a mandrel corresponding to
32、class I I I of table 3. For a period of 5 minutes, apply a vacuum to the hose assembly producing ambient pressure reduced by : 66 % for the hose assemblies of nominal sizes belw 12. 33 % for hose assemblies of nominal sizes above or equal to 12. During this time check free circulation of a ball 1 1
33、of a diameter equal to 80 % of the minimum diameter at the bead of the hose assembly (see table 1). Check of inside diameter (after ageing in liquid only) e 6.4.3.2 After ageing by the liquid or gas and in air 6.4.3.2.1 Low temperature bend test This test is indicated in tables 4 to 7. A hose assemb
34、ly previously aged in the liquid or gas conveyed and a hose assembly aged in air are filled with appropriate liquid and placed for 443 hours in a cold chamber of which the temperature is held : For hose assemblies of classes I I I, IV and V : at - 50 k 2 OC. For hose assemblies of classes I and I I
35、of nominal sizes below or equal to 16 : at - 50 f 2 “C. For hose assemblies of classes I and I I of nominal sizes greater than or equal to 20 : - 40 f 2 “C. While they are still at this temperature and full of fluid, these two hose assemblies are bent to 180 O, once in one direction and once in the
36、other with a rate of one bending every 4 th second on a mandrel of which the diameter is given in table 3. After this test, the hose assemblies shall withstand the proof pressure for 3 to 5 minutes. O i) To avoid the effect of the vacuum, the ball shall be drilled. ._ :- -* *-2.-c : , .-,y, -2, -. 1
37、. I L _I Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-10 200 200 200 250 300 i2 - 250 250 250 300 - - - - AECMA PREN2253 84 B 1012311 0002653 O prEN
38、2253 Page 8 TABLE 3 - Diameter of test mandrel - 8 Dimensions in millimetres 500 600 700 800 - 16 _I 20 350 350 - 25 400 400 Nominal sizes Class I 3 and 4 5 and 6 - 1 O0 1 O0 - I 50 150 - 200 200 - 300 300 II I- 1-1- III 1 O0 150 150 - - - 150 150 - 200 200 - 350 400 - 300 350 400 500 IV V 200 - 250
39、 - 6.4.3.2.2 Impulse test This test is applied only to hose assemblies of classes I I I, IV and V. The test is conducted on : - 2 hose assemblies aged either in the liquid or in the gas conveyed - 2 hose assemblies aged in air - 2 new hose assemblies The hose assemblies are connected to the impulse
40、manifold. The hose assemblies of a nominal diameter of less than 20 shall be held bent at the radius specified for the low temperature bend test (sub subclause 6.4.3.1). The minimum length of the hose assembly is defined by the formula : where D = diameter of mandrel defined in the table 3 DN = nomi
41、nal size Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-AECMA PREN2253 84 m 1012311 0002b54 2 m 1 prEN2253 Page 9 Peak pressure at 150 % for classes I
42、V and V Pak pressure at 125 % for class 111 4- 5%of cycle FIGURE 2 - Diagram of impulses Hose assemblies of a nominal diameter equal to or greater than 20 shall have a total length of 450 mm and shall be straight. The machine shall produce, in the manifold, dynamic pressure impulses of the amplitude
43、s and frequencies given by the diagram in figure 2. The test fluid shall be held at the temperature of 50 1 10 “C measured in the manifold. The number of impulses shall be on average : - Class I II : 100,000 for hose assemblies up to DN = 12 - 75.000 for hose assemblies from DN 16 to DN = 25 50.000
44、for hose assemblies above DN = 25 - Classes IV : 100.000 for hose assemblies up to DN = 10 and V 75.000 for hose assemblies of DN = 12 50.000 for hose assemblies of ON = 16 35.000 for hose assemblies of DN = 20 45.000 without pressure peak for hose assemblies of DN = 25 No leakage or damage shall oc
45、cur during the test. 6.4.4 Other tests (on hose assemblies which have not been aged) 6.4.4. I Tests for external resistance to aircraft liquids This test is indicated in tables 4 to 7. . The hose assemblies are immersed for 48 hours at room temperature in each of the following aircraft liquids : :i
46、. . ._ . . . . Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-r AECMA PREN2253 84 LOL231L 0002655 4 prEN2253 Page 1 O - hydraulic fluid (petroleum bas
47、e or phosphate ester fluid) - lubricant - fuel (iso-octane 70 % -toluene 30 %) -water methanol . The operation shall be carried out in such a way that the fluid cannot enter the interior of the hose assembly, either by plugging the ends of the latter or by keeping them out of the fluid. After this t
48、est, the outer envelope of the hose assembly shall not exhibit any cracks. 6.4.4.2 Test at proof pressure This test shall be conducted on hose assemblies which successfully pass the test of par. 6.4.4.1. The hose assembly is connected to an appropriate fluid system and subjected to proof pressure (P
49、E = 2 PN) for a period from 30 seconds to 5 minutes. This pressure is gradually applied at the rate of 2 MPa (20 bar) to 3 MPa (30 bar) per second. Throughout this test the hose assembly shall show no evidence of leakage or damage. 6.4.4.3 Leakage test This test which appears in tables 4 to 7 shall be conducted on a new hose asse
