1、AECMA PREN2753 87 JOI12311, 0004L07 5 Edition approved for publication 16 February 1987 A. E. C. M. A. STAN DAR D NORME A.E.C.M.A. A.E.C.M.A. NORM Comments should be sent within six months C3 Chairman after the date of publication decision 88, Bd. Malesherbes A.E.C.M.A. Mr ARENA 75008 PARIS - FRANCE
2、 prEN2753 Issue P 1 February 1987 UDC DIT PAR LASSOCIATION EUROPENNE DES CONSTRUCTEURS DE MATRIEL AROSPATIAL 88, boulevard Malesherbes, 75008 PARIS - TL. 45-63-82-85 Key words : ENGLISH VERSION Aerospace series Nuts, anchor, self locking one lug, with counterbore Classification : 1 1 O0 MPa/235 OC S
3、rie arospatiale crous river freinage interne simple patte avec chambrage Classification : 1 1 O0 MPa/235 OC Luft- und Raumfahrt Annietmuttern, selbstsichernd, einseitiger Flansch mit zylindrischer Aussenkung Klasse : 11 O0 MPa/235 OC This standard is initially published on green paper for the needs
4、of AECMA-Members (Association Europenne des Constructeurs de Matriel Arospatial). It has been technically approved by the experts of the concerned AECMA Commission following comment by the manufacturers of the Member countries. After examination and signature of the AECMA Standard Checking Centre (N
5、PS) and formal agreement of the Official Services of the Member countries it will be published in its final version on yellow paper as an AECMA Standard aecma 1987 Issue P 1 prEN2753 Page 3 1 Scope This standard specifies requirements for single lug, counterbored, fixed anchor nuts, with a self-lock
6、ing feature achieved by forming the upper portion out-of-round, the dimensions of which are in conformity with IS0 3168. 2 Field of application These nuts are intended for use in aircraft assemblies, in which the fasteners are mainly subjected to shear loads. The counterbore of nuts with thread diam
7、eter equal to or greater than 4 mm is deep enough to accommodate a bolt shank in excess of assembly thickness, as well as the incomplete threads, The 3 mm diameter nut has no counterbore. They are intended to be used with threaded parts of 1100 MPa i) tensile strength classification. O The cadmium p
8、lating restricts the application to temperatures not exceeding 235 OC. 3 . References IS0 3168, IS0 585511, IS0 585512, IS0 5858, ). IS0 8788, Aerospace - Metric Fasteners - Nuts, anchor, self-locking, fixed, one lug, with counterbore - Dimensions Aerospace construction - MJ Threads - Part 1 : Basic
9、 profile Aerospace construction - MJ Threads - Part 2 : Dimensions for bolts and nuts Aerospace - Fasteners - Self locking nuts with maximum operating temperature less than or equal to 425 OC - Procure- ment specifcation 2) Aerospace - Fasteners - Tolerances of form and position for nuts 2) 1) This
10、strength class applies at room temperatures. e 2) In preparation Previous page is blank AECMA PREN2753 87 M LOL231L OOOLiLO9 7 M Issue P 1 prEN2753 Page 4 EN2000, Aerospace series - Quality assurance requirements for the manufacture and procurement of EN aerospace standard products EN2133, Cadmium p
11、lating of steels with maximum specified tensile strength equal or less than 1450 MPa, and copper and copper alloys - Aerospace series EN2424, Identification marking of standard fasteners - Aerospace series EN2491, Aerospace series - Molybdenum disulfide solid film lubricants for application to remov
12、able fasteners . in titanium, titanium alloy, corrosion resisting steel and cadmium plating steel i) EN2542, Aerospace series - Steel FE-PL43S - 1250 Rm 1400 MPa Bar and wire - De 3 40 mm - Only for Erevaihg torque nuts 2) EN2543, Aerospace series - Steel FE-PL43S - 1250 Rm 1400 MPa - Sheets and str
13、ips - 0,3 - A - 2 mm - Only for-prevailing troque nuts 2) 4 Required characteristics 4.1 Configuration - Dimensions - Tolerances The configuration shall be in accordance with the figure ; the dimensions and tolerances shall conform to the values shown in the figure and in table 1, after cadmium plat
14、ing but before Mos2 lubrication. 4.2 Surface roughness See figure. The values apply before cadmium plating and Mos2 lubrication, they do not apply to the thread, sheared-off edges and punched holes obtained by normal methods of manufacture. 4.3 Materials Steel EN2542 or EN2543. 4.4 Surface treatment
15、 Cadmium plating EN2133, 5 ym minimum on the threads and all areas which can be contacted by a 20 mm diameter ball. On all other areas, a continuous deposit shall be present, but no minimum value is specified. Lubrification by Mos2 EN2491 , mandatory on threads, optional on other surfaces. 2) In pre
16、paration. AECMA PREN2753 87 m L0123Ll OOOYLLO 5 m Issue P 1 prEN2753 Page 5 Break sharp edges 0,l to 0,4 inm Detail X . Radius or chamfer Section Y-Y + 0,2 2 holes S 0 Plain rivet holes I I 1 Optiona flanges i (or reinforcements) . Optional : Countersunk or dimpled river hole 4). . ._ + 0,4 2 holes
17、S o +0.2 2 hole_c S o Dimpled hole Figure - Configuration Not stated details of form, are at manufacturers option. 3) For inspection requirements see clause 7. 4) Choice of realisation left to the manufacturer. AECMA PREN2753 87 LOL231L 0004LLL i Issue P i prEN2753 Page 6 ! .- 8 E E i3 I P . 00 06 h
18、 Co O v) - 5 L 8 t! .- P x ci .- O h e c .- m E O w u) O Q U .I .- s E e rc O u) a U E m L a I io AA . . I r cv- rc O Issue P 1 prEN2753 Page 7 Option Plain rivet holes 5 Designation Hole code - Each nut shall only be designated as in the following example : K Countersunk or dimpled rivet holes L De
19、scription Block NUT, ANCHOR Identity Block EN Number of EN Standard Table 2 Note : If necessary the originator code S9005 may be introduced between the description block and the .identity block. 6 Marking Each nut shall be marked in any of the positions shown on the figure in accordance with EN2424, Style F. 7 Conforming to IS0 5858 except for quality assurance requirements - See EN2000. Tech nical speci fica tion
