1、 AECMA PRENx424B b L0123LL 0010540 314 Srie arospatiale crous river, freinage interne, fixes, simple patte, avec chambrage, en acier rsistant chaud, argents Classification : 1 100 MPa ( temprature ambiante) I425 OC 1 AECMA STANDARD NORME AECMA AECMA NORM I Edition approved for publication prEN 4248
2、Edition P 1 May 1996 C3 Chairman Comments should be sent within six months after the date of publication to PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - E-1 200 BRUXELLES - Tel. (32) 2 775 81 10 - Fax. (32) 2 775 81 11 ICs : 49.040.20 ENGLISH VERSION Aerospac
3、e series Nuts, anchor, self-locking, fixed, single lug, with counterbore, in heat resisting steel, silver plated Classification : 1 100 MPa (at ambient temperature) I425 OC Luft- und Raumfahrt Annietmuttern, selbstsichernd, einseitiger Flansch, mit zylindrischer Aussenkung, aus hochwarmfestem Stahl,
4、 versilbert Klasse : 1 100 MPa (bei Raumtemperaturl I 425 OC 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 t
5、he experts of the concerned Technical Committee following comment 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 stan
6、dard. 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 European Standard to CEN (European Committee for Standardization) for formal vote. 1996-05-31 AECMA Gulledelle 94 B-
7、1200 BRUXELLES Mr Arena 1 I I aecrna 190 AECMA PRENx4248 96 m LOL23LII 0010542 II97 m Page 3 prEN 4248 : 1996 1 Scope This standard specifies the characteristics of self-locking, fixed, single lug anchor nuts, with counterbore, in heat resisting steel, silver plated. Classification : 1 100 MPa 1) /
8、425 OC 2) 2 Normative references IS0 3168 IS0 5855-2 IS0 5858 IS0 8788 EN 2000 EN 2424 EN 2786 EN 3042 TR 3791 Aerospace - Self-locking, fixed, single-lug anchor nuts with counterbore, classification 1 100 MPa / 235 OC Aerospace - MJ threads - Part 2 : Limit dimensions for bolts and nuts Aerospace -
9、 Self-locking nuts with maximum operating temperature less than or equal to 425 OC - Procurement specification Aerospace - Fasteners - Tolerances of form and position for nuts Aerospace series -Quality assurance - EN aerospace products - Approval of the quality system of manufacturers Aerospace seri
10、es - Marking of aerospace products Aerospace series - Electrolytic silver plating of fasteners 3) Aerospace series - Quality assurance - EN aerospace products - Qualification procedure Aerospace series - Materials for all metal self-locking nuts and thin wall inserts of temperature classes 9 425 OC
11、4) 1) Corresponds to the minimum tensile stress which the nut is able to withstand at ambient temperature without breaking or cracking when tested with a bolt of a higher strength class. 2) Maximum temperature that the nut is able to withstand, without permanent alteration to its original characteri
12、stics, after ambient temperature has been restored. The maximum temperature is conditioned by the dimensions., 3) Published as AECMA Prestandard at the date of publication of this standard 4) Published as AECMA Technical Report at the date of publication of this standard AECMA PRENm46411 96 L01233L
13、0030543 023 m Page 4 prEN 4248 : 1996 3 Required characteristics 3.1 See figure 1 and table 1. Dimensions and tolerances are : in conformity with IS0 3168, expressed in millimetres and apply after surface treatment. Details of form not stated are at the manufacturers option. The cap shall remain joi
14、ned (type of attachment at the users discretion) to the nut at the maximum operating temperature. See test conditions in IS0 5858. Configuration - Dimensions - Masses 3.2 IS0 8788 Tolerances of form and position 3.3 Materials TR 3791 3.4 Surface treatment EN 2786, thickness : - on external surfaces
15、: 5 pm to 15 pm ; - on pitch diameter : 5 pm min. for nuts MJ6 and larger. Nuts MJ5 and smaller shall show complete coverage over complete profile. AECMA PRENa4248 Diameter code 030 040 050 060 Remove sharp edges 0,l to 0,4 Thread 1) C D E F G H J2) K L M N3) P4) O R S T V Mass5) max. max. min. min.
16、 max. max. rnax. max. max. rnax. max. a rnax. I0,25 2,s 1,6 1,8 23 2,l 3 2,5 - 43 MJ30,5-4H6H - - 66 - 4,6 6 17.7 3,2 - - MJ40,7-4H6H 6.4 8,5 4.4 2,2 6,2 8 23.7 5,8 1.1 11 13 MJ5x0,8-4H6H 0,4 7,4 9,5 8 5.5 2,4 7,3 9 25,2 6,9 - 11,4 13,4 - 3,5 23 MJ6xl-4H5H - 8,8 11 6.5 8,7 10 27,7 8,l 1.3 12,7 14,7
17、4 4 - 96 3032333 0030544 TbT 9 080 MJ8xl-4H5H 100 MJl01.25-4H5H - 0,s Page 5 prEN 4248 : 1996 - 2,7 - 3,5 - 11,7 85 10,Q 13 29.7 9,Q I,? 15 18 3 5 5.7 7,5 - 83 - - 13 10,5 3 12,9 16,2 34,3 12 1,9 - - 4,5 3,5 6 6,6 11,5 Options : countersunk rivet holes (when specified by the user) may be dimpled or
18、cut countersunk (at the manufacturers option). Y-Y O o N N +I +I O O O o 9 s Flange or N 1- 1 be;optonal Form out-of-round in this area to achieve the self-locking torque requirement 2). Radius / I H I 1 nr Configuration with cap m 1) These values in micrometres apply before surface treatment. They
19、do not apply to threads, punched holes or sheared edges, the surface texture of which will be as achieved by usual manufacturing methods. 2) Tooling marks are permitted in this area. Figure 1 Table I AECMA PRENa4248 b = 1012311 0010545 Tb Option Plain rivet holes Dimpled or countersunk rivet holes P
20、lain rivet holes + cap Dimpled or countersunk rivet holes + cap Page 6 prEN 4248 : 1996 Code - (hyphen) K B A 4 Designation EXAMPLE : Description block Identity block Number of this standard ,.,O Rivet hole and cap code (see table 2) Diameter code (see table 1) NOTE : If necessary, the code 19005 shall be placed between the description block and the identity block. Table 2 5 Marking EN 2424, style N. See figure 1. 6 Technical specification IS0 5858, except for : - Approval of manufacturers : see EN 2000 ; - Qualification of products : see EN 3042.
