1、A. E.C. M .A. STANDARD NORME A.E.C.M.A. A.E.C.M,A. NORM prEN2948 Issue P 1 June 1986 DIT PAR LASSOCIATION EUROPENNE DES CONSTRUCTEURS DE MATERIEL AROSPATIAL 88, boulevard Malesherbes, 75008 PARIS -TEL. 45-63-82-85 UDC : Key words : ENGLISH VERSION Aerospace series - Washers, tab Heat resisting steel
2、 Srie arospatiale Freins dcrous en tle en acier rsistant chaud Luft- und Raumfahrt Sicherungsbleche mit Lappen aus hochwarmfestem Stahl This standard is initially published on green paper for the needs of AECMA-Members (Association Europenne des Constructeurs de Matriel Arospatial). It has been tech
3、nically 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 (NPS) and formal agreement of the OfficialServices of the Member countries it will be published in i
4、ts final version on yellaw paper as an AECMA Standard. Nota - Extra copies can be supplied by B.N.A.E. - 8, rue Moreau-Vauthier - 92100 BOULOGNE-BILLANCOURT Edition approved for publication Comments should be sent within six months C3 Chairman after the date of Dublication decision 2 June 1986 A.E.c
5、.M.A. 88, Bd. Malesherbes Mr ARENA 75008 PARIS - FRANCE 0 aecma 1986 AECMA PREN2798 86 m LOL23LL 0004598 2 W _ issue PI prEN2948 Page 3 1 Scope and field of application This standard specifies the characteristics of heat resisting steel tab washers for use in aerospace applications, at temperatures
6、below 650 C. They are intended primarily for use under hexagon nuts. Their use under hexagon head bolts is conditional upon the user accepting the possibility of some fouling , 2 References EN2175 Heat resisting steel FE-PA 93 HT, s-olution treated and precipitation treated - Sheet and strips a - 10
7、00- 5000 On visual examination the tab washers shall be free from burrs, scratches and cracks. The minimum quantity to be checked is given in table 2. - 30 Table 2 20 2000- 5000 - 6.3 Bend test One tab washer per 1OOCi (v-ith three samples ninilmm) shall be ossembled Ender normal opereting conditions. The two locking tabs shall be folded back and straightened twice, as required for this purpose. The locking tabs shall not crack and shall remain sufficiently stiff so as to ensure adequate locking, 223MR0386T4
