1、STD.AECMA PREN 2900-ENGL 1998 lOl23Ll 00L507b 5Ll m Declassification approved AECMA STANDARD NORME AECMA AECMA NORM C4 Chairman Comments should be sent within six months after the date of publication to prEN 2900 Edition P 2 September 1998 PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIE
2、S (AECMA) Gulledelle 94 - 8-1200 BRUXELLES - Tel. (+32) 2 775 81 10 - Fax. (+32) 2 775 81 11 UDC: 629.7.02. : 658.56 Supersedes issue P 1 April 1989 Key words: Aeronautical industry, clamps, specification ENGLISH VERSION Srie arospatiale Colliers Spcification technique Aerospace series Clamps Techni
3、cal specification Luft- und Raumfahrt Schellen Technische Lieferbedingungen This “Aerospace Series“ Prestandard bas been drawn up under the r (The European Association of Aerospace Industries) of AECMA-Members. It has been technically approv Technical Committee following comment by the Memb Subseque
4、nt to the publication of this Prestanrd, of the standard. After examination an Checking Centre (NPS) and formal tries it will be submitted as a draft stion) for formal vote. Replace page 1 of the previous issue by this page 1998-09-30 AECMA Gulledelle 94 6-1 200 BRUXELLES Mr Staib aecma 1998 Copyrig
5、ht Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Issue P 1 prEN 2900 Page 2 Contents 1 2 3 4 5 6 7 8 9 Scope Field of application Re fer en ces Definitions Req
6、uired characteristics, inspections and test methods Quality assurance Acceptance conditions Packaging Certificate of conformity Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted with
7、out license from IHS-,-,-I AECMA PREN2700 87 L0123LJ OOOLl347 3 W - I Issue P 1 prEN 2900 Page 3 1 Scope This standard specifies the required characteristics, inspections and tests, quality assurance and qualification, acceptance and delivery conditions of clamps designed to support, and in conjunct
8、ion with suitable rubber hoses, form joints in fluid system pipe lines. 2 Field of application These clamps are intended to be used as specified in the product standards, 3 References IS0 2859 IS0 6771 IS0 8625 EN 2000 EN 2901 EN 2902 EN 2903 EN 2904 EN 2905 EN 3276 EH 3277 - Sampling procedures and
9、 tables for inspectior: by attributes - Aerospace construction - Fluid systems and components - Pressure and temperature - Classifications - Aerospace fluid systems and components - Terminology - General pressure terms and definitions 1) - Aerospace series - Quality assurance requirements for the ma
10、nufacture and procurement of EN aerospace standard parts 33 - Aerospace series - Clamps, loop (Pl type) with rubber cushioning, in corrosion resisting steel - Diniensions - Masses 2j - Aerospace series - Clamps, loop (IP* type) with rubber cushioning in aluminium alloy - Dimensions - Niasses 11 -Aer
11、ospace series - Clamps, worm drive - Dimensions - Niasses 2) -Aerospace series - Clamps, saddle, aluminium alloy - Dimensions - Masses 2) -Aerospace series - Rubber cushioning for clamps - Dimensions - Masses 2j -Aerospace series - Clamps, loop, (Pl type) without rubber cushioning, corrosion resisti
12、ng steel - Dimensions and masses 23 -Aerospace series - Clamps, loop, type without rubber cushioning, aluminium alloy - Dimensions and masses 1) 4 Definitions 4.1 A clamp loop is a band of metallic material with or wihout a rubber cushion intended to support systems pipe lines. Single bolt attachmen
13、t. 4.2 A clamp saddle is a two part band of metallic material with rubber cushioning intended to support systems pipe lines. Two bolt attachment, 4.3 A clamp worm drive is a band of material fitted with an adjustment device intended, in conjunction with a suitable hose, to provide a pipe to pipe joi
14、nt. 44 Pressure terms and definitions see IS0 8625. 12 In preparation 2) Published as AECMA pre-standard 3: Published as AECMA standard Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permit
15、ted without license from IHS-,-,-AECMA PREN2900 89 LOL23Ll 0004348 5 Issue P 1 prEN 2900 Page 4 5 The required characteristics, inspections and test methods are specified table 1, kcyuired characteristics and test methods 5.4 Table 1 Surface Clause I Characteristic 5.5 I Tightening range 5.1 I Mater
16、ials 5.2 i Dimensions and I to1 erances I I 5.3 I Marking I l Requirement They shall conform with the requirements of the product standards, rubber cushioning to EN 2905. They shall conform with the values quoted in the product standards. The clamps shall be marked to the requirements of the product
17、 standards. It shall be legible and not degrade the material or adversely affect the part. . The clamps shall be free from burrs, sharp edges, irregular surfaces on the clamp band and any other defect which could affect their service use. Worm drive clamps shall be designed to operate within the ful
18、l tightening range specified in the product . standard. When the clamp is fully opened it shall be possible to re-engage the band/screw easily so that it passes onto the closing range without any noticeable resistance. inspection or test method The test and acceptance certificate for the semi -fi ni
19、 shed product may be used. They shall be measured using suitable instruments Visual examination Visual examination The maximum and minimum values of the tighteging range shall be checked by dimension and inspection. The maximum value shall be checked by mounting the clamp on a mandrel and the band/s
20、crew engaged while the clamp is opened and the closing process i ni ti ated. . . ./. . . i 17 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 PRE
21、N2900 W 1012311 OOOLt349 7 W C1 ause 5.6 5.7 5.8 Characteristic Tightening torque (Normal ) U1 timate torque Pressure test: Issue P 1 prEh 2900 Page 5 Table 1 (continued) Requirement Worm drive clamps shall be capable of being tightened to the values specified in table 2. They chal apply over the fu
22、ll tighten ng range. Worm drive clamps shall be capable of vii thstandi ng a tightening torque of twice the values specified in table 2 without failure. Worm drive clamps assembled with a suitable hose shall be subjected to a pressure test. The assembly shall be capable of withstanding the pressures
23、 specified in table 3. Inspection or test method The clamps shall be mounted on a mandrel of nominal diameter and tightened to the torque val ues specified. There shall be no deformation of screw threads or band slots. The test shall be repeated on mandrels of maximum and minimum diameter The clamps
24、 may be lubricated or dry. The clamps shall be mounted on a mandrel of nominal diameter. The clamp shall then be tightened until failure occurs. The torque recorded shall be in excess of the values specified. The test apparatus shall conform with figure 1 and the worm drive clamps torque tightened t
25、o the values specified in table 2. The fluid to be used for the test shall be water at room temperature. The assembly shall be allowed to settle prior to application of pressure. After this period the pressure chal 1 be increased at a rate of 10 kPa/second until leakage or failure occurs. The record
26、ed pressure at failure shall be in excess of the values specified. . . ./* . , Q = Qualification A = Acceptance Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from
27、 IHS-,-,-AECMA PREN2900 - 89 m 1032311 OOOLI350 3 W Issue P 1 prEN 2900 Page 6 Table 1 (continued) Characteristic Requirement Res; stance to Worm drive clamps shall oscillation neither loosen nor fail when subjected to oscillation. Re-usabi 1 i ty Repeated assembly shall not cause any change in clam
28、p dimensions or affect the correct functioning. Inspection or test method The test apparatus shall conform with figure 2 and the worm drive clamps torque tightened to the values specified in table 2, The position of the tightening jaws shall be marked. One end of the hose shall be subjected to 1500
29、oscillations per minute of an amplitude of 2 3,2 mm for 24 hours. During the test a sufficient amount of a suitable oil shall be pumped through the hose to stabilize the temperature at 120 ?C 2 3 ?C and the pressure to the values specified in table 3, After 2h hours of oscillation it shall be checke
30、d whether the screws have loosened. The clamps shall be loosened and tightened again with the same tightening torque to reveal any slackening of the hose. The hose shall be examined for cuts which might have been caused by the clamp. To verify repeated assembly the clamps shall be installed 5 times
31、on a maximum diameter mandrel. Clamps support (Loop) shall be opened so that they pass over the mandrel. Worm drive clamps shall be opened by detaching the band from the screw and passing over the mandrel. On completion of the test the dimensions of the clamps shall be checked using sui table instru
32、ments and inspected for defects likely to affect performance, . . 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-,-,-I AECMA PREN2900 89 U 1012311
33、 OOOL)351 5 mp Issue P 1 prEN 2900 Page 7 Tight-rom ening range Table 2 - lightening torques r 8 12 16 20 25 32 40 50 60 70 80 90 100 11 120 130 140 to 16 20 25 32 40 5 60 70 80 90 100 110 120 130 140 150 169 A 3 Tightening I clamp sizes I k Pi4 I 016 020 to 032 3300 2500 040 to 050 060 to 070 2100
34、1700 080 to O90 0100 to 0160 1400 700 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-,-,-I AECMA - - - PREN2900 A W 1012311 OOOY352 i Issue P 1 prEN 2900
35、Page 8 Pressure connect ion Figure 2 - Oscillation resistance test apparatus 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 PREN2700 87 m LOL231
36、1 0004353 9 W I Issue P 1 prEN 2900 Page 9 6 Quality assurance G .1 hrianufacturers approval See EN 2000. 6.2 Product qualification To obtain qualification for clamps the manufacturer shall observe the schedule and requirements of table 4. No change in material or design is permitted without prior a
37、pproval of the qualification authorities who granted the initial approval. 7 Acceptance conditions 7.1 Ganufacturers responsibility 7.2 Inspection and tests The inspections ana tests to be performed by the manufacturer for the acceptance of a batch of clamps (worm drive and loop type) shall be those
38、 listed in table 5. A random sample shall be selected from each batch in accordance with the procedures listed in IS0 2859. The inspection level and acceptance quality level AQL shall be as specified in table 5. 7.3 Definition of a batch An inspection batch shall consist of clamps of a particular si
39、ze and material produced under essentially the same manufacturing conditions and presented for inspection at the sanie time. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without
40、 license from IHS-,-,-Issue P 1 5.2 5.4 5.5 5.6 5.7 - 5.8 prEN 2900 Page 10 Ali test samples I_ 2 12 Table 4 - Inspection and tests .to be performed for qualification 2 3 Inspection or test Test PJ o I Dimensions and tolerance: Mark i rig 4 5 Surface appearance Tightening range 6 7 8 9 10 I Re-usabi
41、lity Tightening torque (normal) Ultimate torque Pressure test Resistance to oscillation I 5.11 Defined No, of sample 5 5 parts I 2 *- 4 The tests of the worm drive clamps will be performed with each nominal size. Table 5 - Inspection and tests to be performed for acceptance lnspection or test Define
42、d in Ma ter ia Is 5.1 Dimensions Band width, and tolerances thickness and loop diameter Bolt hole and pos t ion - 5.2 Marki ng Surface appearance Tightening range 5.6 Ke-usabili ty - IS0 2859 Inspection - Level 1 AQL At ma nu fac tu rer s option 1 .O (Major) 4.0 (Minor) 4.0 (Minor) 4.0 (Minor) 4.0 (
43、Minor 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 PREN2900 89 = L0123LL 0004355 2 Issue P 1 prEN 2900 Page 11 8 Packaging The clamps shall be
44、 packed so as not to be damaged during transit. Individual packaging is preferred. They shall be protected against humidity, corrosion, dirt and any of other haririfiil attacks. The packaging material ir1 contact with the clamps shall provide this protection, The following shall appear on each indiv
45、idual package : - name of manufacturer - quantity - identity block of the product standard - date of packaging - cure date of cushioning material. At least the following shall appear on collective packages for transport : - name of manufacturer - number of order or contract - quantity - description
46、- identity block of the product standard - reference of manufacturer. 9 Certificate of conformity All deliveries of clamps referring to this standard shall be accompanied by a certificate of conformity. 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-,-,-
