1、AECMA PREN3LLiB 89 i - Edition approved for publication Comments should be sent within six months after the date of publication decision 88, Bd. Malesherbes 5th October 1989 A.E.C.M.A. 75008 PARIS - FRANCE A. E. C. M .A. STAN DARD NORME A.E.C.M.A. A.E.C.M.A. NORM C8 Chairman Mr WILLIAMS prEN 3148 Is
2、sue P 2 October 1989 UDC : DIT PAR LASSOCIATION EUROPENNE DES CONSTRUCTEURS DE MATRIEL AROSPATIAL 88, boulevard Malesherbes, 75008 PARIS -TL. 45-63-82-85 Supersedes Issue P 1 October 1988 Key words : ENGLISH VERSION Aerospace series Shank nuts, self-locking, flange restrained Installation procedure
3、Srie arospatiale crous sertir, auto-freinants, flancs de retenue Procdure dinstallation Luft- und Raumfahrt Einnietmuttern, selbstsichernd, mit Anlageflche Ein bauverfahren This Aerospace Series pre-standard has been drawn up under the responsibility of AECMA (Association Europenne des Constructeurs
4、 de Matriel Arospatial). It is published on green paper for the needs of AECMA-Members. It has been technically approvedby the experts of the concerned Commission following comment by the Member countries. Subsequent to the publication of this pre-standard, the technical content shall not be changed
5、 to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and signature of the AECMA Standard Checking Centre (NPS) and formal agreement of the Official Services of the Member countries it will be submitted as a draft
6、European Standard to CEN (European Committee for Standardization) for final vote. 1 Scope and field of application This process standard details the installation of shank nuts to prEN2910 and prEN2911 in engine components. It applies to flange restrained shank nuts and shall be observed whenever inv
7、okedin drawings and working documents. It is to ensure proper installation for adequate retention of the shank nuts and freedom from damage to the components involved. 2 References EN 2910 EN“ ,2911 Aerospace series -Shank nuts, self locking, flange restrained, in heat resisting steel FE-PA92HT (A28
8、6) unplated-Classification: 1100 MPa/650 OC 1 Aerospace series-Shank nuts, self locking, flange restrained, in heat resisting steel FE-PA92HT (A286) silver plated-Classification: 1100 MPa/650 OC1 ) 3 Swaging procedure Swaging of shank nuts is carried out by deforming the end of the shank using a 60
9、swaging cone. Shank nuts are swaged with the aid of a swaging tool either manually or by machine. Swaging cones and anvils of the swaging tools are replaceable. Before swaging, make sure you are using the proper combination of cone, anvil and shank nut (see Table in clause 4) to prevent excessive lo
10、ad on the components. To prevent damage to the locking element of the shank nut the tool shall not be located on the end of the nut locking element, but on the flange of the shank nut. The component flange shall be firmly held against the nut before swaging commences because the angle of the cone wi
11、ll not automatically ensure tightness. Care shall be taken not to damage the components during assembly. Figure 1 shows a swaged shank nut. ! /- Componer.l flange Shank nut end with locking element Flange for locating swaging tool Figure 1 - Swaged shank nut -_. - -_ 1 ) Pub1 ished as AEC!tA pre-sta
12、ndard I ;AECMA_PREN3LLiB By M LOL2311 000Lt91b 5 M prEN 3148 Page 4 4 Swaging tool dimensions The dimensions of the swaging cone and the anvil to be used for swaging of the relevant shank nut sizes are shown in Figure 2 and Table. All other tool dimensions depend on the means of production of each u
13、ser of the shank nuts. Swaging cone J Figure 2 - Tool dimensions Table - Dimensions Dimensions in millimetres Anvil Diameter Shank nut lcode I thread size 050 MJ50,8 - 4H6H 795 343 897 060 MJ6xl - 4H5H 8,5 4,8 997 070 MJ7xl - 4H5H 995 498 10,7 080 MJ8xl - 4H5H 11,o 594 11,7 h AECMA PBEN3L48 89 a LO_
14、12311 00049117 7 W prEN 3148 Page 5 5 Controlling after swaging After swaging the following conditions shall be accomplished: - The shank shall be underflush after swaging to avoid fouling the mating flange (see Figure - Manual rotation of the shank nut up to the trap shall be permissible but there
15、shall be no axial movement. - The swaged shank shall show no cracks or corrugations. - The bearing surface of the shank nut shall bear completely on the base. - In case of silver coated shank nuts to prEN 2911: During swaging the silver coating inside the shank may be subject to rub off, which is permissible. No touching up is required, but any loose flakes of silver coating are to be removed. 1).
