1、STD-AECMA PREN 3076-ENGL 1996 10L2311 0014863 223 AECMA STANDARD NORME AECMA AECMA NORM prEN 3078 Edition P 1 September 1998 PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - B-1200 BRUXELLES - Tel. (+32) 2 775 81 10 - Fax. (+32) 2 775 81 11 ICs: Descriptors: ENGL
2、ISH VERSION Aerospace series P, Q and saddle clamps with rubber cushion Technical specification Srie arospatiale Colliers en “P“, serrage central et “LI“ avec profils en lastomre Spcification technique Luft- und Raumfahrt Schellen in P, Q- und Sattel-Form mit Profilgummi Technische Lieferbedingungen
3、 This “Aerospace Series Prestandard has been drawn up under the responsibility of AECMA (The European Association of Aerospace industries). It is published on green paper for the needs of AECMA-Members. It has been technically approved by the experts of the concerned Technical Committee following co
4、mment by the Member countries. Subsequent to the publication of this Prestandard, the technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and signature of the AECMA Standard
5、Checking Centre 1NPSI and formal agreement of the Official Services of the Member countries it will be submitted as a draft European Standard to CEN (European Committee for Standardization) for formal vote. Nota - Extra copies can be supplied by B N A. - Technopolts 54 - 199, rue Jean-Jacques Rousse
6、au - 921 38 ISSY-LES-MOULINEAUX CEDEX C4 Chairman I Comments should be sent within six months after the date of publication to I Edition approved for publication AECMA Gulledelle 94 1998-09-30 6-1 200 BRUXELLES Mr Staib aecrna 1998 Contents list 1 Scope 2 Normative references 3 Definitions 4 5 Quali
7、ty assurance 6 Delivery condition 7 Packaging and storage Required characteristics, method and inspection test STDmAECMA PREN 3078-ENGL L99 H LOL23LL OOL48b5 OTb Page 3 prEN 3078: 1998 I Scope This standard specifies the required characteristics, inspection test methods, quality assurance and delive
8、ry conditions, for P, Q and saddle clamps with rubber cushion, used for aerospace applications. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and
9、 the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. IS
10、0 468: 1982 IS0 2859-1: 1989 IS0 3161: 1996 IS0 5855-2: 1988 EN 2000 EN 10204 Surface roughness - Parameters, their values and general rules for specifying requirements Sampling procedures for inspection by attributes - Part 1 : Sampling plans indexed by acceptable quality level (AQL) for lot-by-lot
11、 inspection Aerospace - UNJ threads, with controlled root radius, for aerospace - Inch series Aerospace - MJ threads - Part 2: Limit dimensions for bolts and nuts Aerospace series - Quality assurance - EN aerospace products - Approval of the quality system of manufacturers Metallic products - Types
12、of inspection documents 3 Defin itions For the purpose of this standard, the following apply: 3.1 Clamps 3.1 .I “P“ clamp A single metal strip formed into a “P loop“ (see figure 1. Used to support fluid pipes or cable bundles. Retained by a single fastener. 3.1.2 “Q clamp A single metal strip formed
13、 into a “Q loop“ (see figure 2). Used to support fluid pipes or cable bundles. Retained by a single fastener. 3.1.3 “Saddle“ clamp Two metal strips, each with a cushion. The top and bottom parts are formed into a “saddle“ (see figures 3 and 4). Available in two versions: Type 1, fixed and type 2, sl
14、iding. Used to support fluid pipes or cable bundles retained by two fasteners. 3.2 Quality assurance 3.2.1 Production batch A definite quantity of some commodity or service produced at one time under conditions that are presumed uniform. STD=AECMA PREN 3078-ENGL 1998 = IaOl12311i 00148bb T32 Page 4
15、prEN 3078: 1998 4.2 4.3 4.4 3.2.2 Acceptable quality level When a continuing series of batches is considered, a quality level which for the purpose of sampling inspection is the limit of a satisfactory process average. Dimensions and tolerances Mass Marking 3.2.3 Major defect A defect other than cri
16、tical, that is likely to result in a failure or to reduce materially the usability of the considered product for its intended purpose. 4.5 3.2.4 Minor defect A defect that is not likely to reduce materially the usability of the considered product for its intended purpose, or that is a departure from
17、 established specification having little bearing on the effective use in operation of this product. Surface appearance 4 Required characteristics, inspection and test methods 4.6 The required characteristics, inspection and test methods, are specified in table I. Additional tests may be defined on a
18、 contractual basis between manufacturer and user. Table i: Required characteristics Surface treatment 1; I Characteristics Materials Requirements In accordance with the product standard or design documentation. In accordance with the product standard or design documentation. In accordance with the p
19、roduct standard or design documentation. In accordance with the product standard or design documentation. It shall be legible and shall not adversely effect the material or the functioning of the clamp Clamps shall be free of burrs, sharp edges, surface defects throughout and any other defect likely
20、 to affect their use in service In accordance with the product standard or design documentation. Inspection and test methods Metal strip: - Chemical analysis or certificate of compliance issued by semi-finished product manufacturer - Hardness or tensile test - Certificate of compliance Cushion: Shal
21、l be measured with suitable equipment Samples (refer to 5.1) All clamps Suitable methods Visual examination: - Samples (refer to 5.1) - All clamps Visual examination: - Samples (refer to 5.1) - All clamps Visual examination - A X - X X X X - B X - X X X A: Product acceptance B: Production batch acce
22、ptance STDgAECMA PREN 3078-ENGL 1998 1012311 0014867 979 m 50d180 80d186 Page 5 prEN 3078: 1998 0,12 to 0,15 0,15 to 0,20 4.7 Test conditions 4.7.1 Test temperature Unless otherwise specified, it will be between 15 OC and 25 OC. 4.7.2 Clamp attachment Unless otherwise specified, bolts used for clamp
23、 attachment shall be made of steel with a resistance greater than or equal to 1 100 MPa and with a nominal diameter MJ 5 x 0,8 4h6h as per IS0 5855-2 for metric series clamps or 1900-32 UNJF-3A as per IS0 3161 for inch series clamps. 4.7.3 Test mandrel 4.7.3.1 All mandrels used for the test shall ha
24、ve a diameter D smaller than the nominal diameter of the clamp by a given value M specified in table 2 (D = d - nn), and a roughness of Ra = 1,6 pm according to IS0 468. Test mandrel for P, Q and type 1 saddle clamps Table 2: Diameter of test mandrels Dimensions in millimetres I Clamp size I M I 3sd
25、s18 I 0,04 to 0,06 I 18 d 30 I 0,06 to 0,08 I 30 dl 50 I 0,08 to 0,12 Test mandrel straightness: 2 mm over a measured length of 100 mm. 4.7.3.2 All mandrels used for the tests shall have a diameter greater than the nominal diameter of the clamp by 0,2 mm and a roughness of Ra = I ,6 pm according to
26、IS0 468. Test mandrel for type 2 saddle clamps 4.7.4 Check of dimensions When axial load is specified on the product standard, this load and all dimensions shall be measured without shim but with the relevant test mandrel (see 4.7.3). When no axial load is specified, the following inspections apply.
27、 STDmAECMA PREN 3078-ENGL 1998 m 1012313 0034868 805 m Page 6 prEN 3078: 1998 4.7.4.1 When the clamp dimensions are measured with shim($ of thickness S and a mandrel of diameter D, they shall be in accordance with the relevant product standard. Check of dimensions for P, Q and type 1 saddle clamps M
28、andrel I Figure I: P clamp Mandrel (as per 4.7.3.1) Figure 2: Q clamp Mandrel S Figure 3: Type 1 saddle clamp STD-AECMA PREN 3078-ENGL 1998 LO32333 0034869 741 Page 7 prEN 3078: 1998 4.7.4.2 Check of dimensions for type 2 saddle clamps Dimensions in millimetres Mandrel (as per 4.7.3.2) Shim ,. Figur
29、e 4: Type 2 saddle clamp Shim 0.2 When mounted with shims and mandrel as shown on figure 4, there shall be: - no clearance between mandrel and cushion; - no significant cushion deformation. Page 8 prEN 3078: 1998 1 Marking 5 Quality assurance 1 Surface appearance 5.1 Approval of manufacturer Accordi
30、ng to EN 2000. I Surface treatment 5.2 Acceptance conditions The acceptance of a delivery batch shall be in accordance with this document. Samples will be selected from each batch in accordance with the procedures specified in IS0 2859-1. The inspection levei and the acceptance quality level are def
31、ined in table 3. I 4.4 I 4.0 minor a) Defects classification Defects are classified in table 3 according to the effect they have on safety and usability. Definition of classes shall be in accordance with IS0 2859-1. b) Inspection level The following Acceptable Quality Level (AQL) shall apply to the
32、defect classifications defined in table 3. Failure class Major: AQL 1 .O Failure class Minor: AQL 4.0 Defined in Table 3: Acceptable Quality Level (AQL) IS0 2859-1 Inspection AQL Level 1 Inspection or test 4.1 4.2 Materials 1.0 major 1.0 major Dimensions - Nominal diameter and Tolerances - Cushion t
33、hickness - Clearance F - Width and thickness of metal strip - All diameters for clamp attachment 4.3 - All other dimensions Mass 4.0 minor 4.5 4.6 4.0 minor I .O major 4.2 I 4.0 minor 5.3 Users quality control The user may, on acceptance of a delivery batch, proceed to inspect it by using the method
34、s specified in 4.7 in full or in part, to ensure that items conform to the required quality level and to determine whether the batch is acceptable. This inspection can be carried out in the users laboratory or, by special agreement, in the manufacturers laboratory. 5.4 Rejection Parts subjected to n
35、on-destructive tests and failing to conform to the requirements of these tests shall be rejected. Parts identified as Major defects during acceptance test require a rejection of all parts as above. Parts identified as Minor defects require the definition of a procedure by the users quality assurance
36、 department. 6 Packaging and storage The clamps shall be conditioned so that they cannot be damaged during transportation. The clamps shall be protected from humidity, corrosion, dirt and all other noxious attacks. The packaging material in contact with the clamps shall provide this protection. 6.1
37、The following information shall appear on each parcel: - Name of manufacturer - Quantity - Product standard identification box - Date of packaging 6.2 The following informations shall appear on collective packings, for transport: - Name of manufacturer - Order or contract number - Quantity - Designation - Product standard identification box 7 Certificate of compliance with the order According to EN 10204, 2.1.
