1、STD-AECMA PREN 3732-ENGL 1977 LOL23LL 0033283 737 AECMA STANDARD prEN 3912 NORME AECMA Edition P 1 AECMA NORM July 1997 PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - 8-1200 BRUXELLES - Tel. (+32) 2 775 81 10 - Fax. (+32) 2 775 81 11 Edition approved for public
2、ation ICs : 49.040.20 Comments should be sent within six months after the date of Dublication to C8 Chairman Descriptors : ENGLISH VERSION Aerospace series Bolts, pan head, six lobe recess, relieved shank, long thread, in heat resisting steel FE-PA92HT (A286), silver plated Classification : 1 100 MP
3、a (at ambient temperature) / 650 OC Srie arospatiale Luft- und Raumfahrt Vis tte cylindrique, empreinte six lobes, ft dgag, filetage long, en acier rsistant chaud FE-PA92HT (A2861, Flachkopfschrauben, Sechs-Bogenzahn, Innenantrieb, langes Gewinde, aus hochwarmfestem Stahl FE-PA92HT (A2861, argentes
4、versilbert Classification : 1 100 MPa Klasse : 1 100 MPa ( temprature ambiante / 650 OC (bei Raumtemperatur) I650 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 need
5、s of AECMA-Members. It has been technically approved by the 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, physical
6、ly 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 European Standard to CEN (European Committee for Standardiz
7、ation) for formal vote. 1997-07-31 AECMA Gulledelle 94 B-1200 BRUXELLES Mr Feltham aecma 1997 STD-AECMA PREN 3712-ENGL 4997 1012311 001328i b75 = Page 3 prEN 3912 : 1997 1 Scope This standard specifies the characteristics of pan head bolts with six lobe recess, relieved shank and long thread, in FE-
8、PA92HT, silver plated, for aerospace applications. Classification : 1 100 MPa / 650 “C *) NOTE : Taking account of the recess geometry, the strength class to be used for the seating torque calculation shall not be greater than 900 MPa. 2 Normative references IS0 3353 IS0 5855-2 EN 2399 EN 2424 EN 27
9、86 EN 3685 EN 3761 EN 3905 EN 391 1 Aerospace - Rolled threads for bolts - Lead and runout requirements Aerospace - MJ threads - Part 2 : Limit dimensions for bolts and nuts Heat resisting steel FE-PA92-HT - R, 2 900 MPa - Bars for forged bolts - 0 I 25 mm - Aerospace series 3, Aerospace series - Ma
10、rking of aerospace products Aerospace series - Electrolytic silver plating of fasteners 4, Aerospace series - Bolts in heat resisting steel, FE-PA92HT (A286) - Classification : 1 100 MPa / 650 “C - Technical specification 4, Aerospace series - Heat resisting alloy FE-PA2601 - Softened and cold worke
11、d - Bar for forged fasteners - il a 50 mm - 1 100 MPa s R, a 1 300 MPa 4, Aerospace series - Six lobe recesses for bolts - Technical specification 4, Aerospace series - Six lobe recess - Geometrical definition 4, 3 Required characteristics 3.1 See figure 1 and tables 1 and 2. Dimensions and toleranc
12、es are in millimetres. They apply after silver plating. 3.2 Materials EN 3761 or EN 2399 with exception of final heat treatment which shall meet EN 3761 (reference heat treatment and relating mechanical properties). 3.3 Surface treatment Configuration - Dimensions - Tolerances EN 2786 Thickness : -
13、thread : 3 pm to 6 pm shall be measured at the pitch diameter ; - other areas may show complete coverage, without thickness requirement. 1) Minimum tensile strength of the material at ambient temperature 2) Maximum test temperature of the parts 3) Published as AECMA Standard at the date of publicati
14、on of this standard 4) Published as AECMA Prestandard at the date of publication of this standard Previous page is blank STD-AECMA PREN 3712-ENGL 1977 1012311 0033285 501 Page 4 piEN 391 2 : 1997 3y oy oy OYE Values apply before silver plating. Remove sharp edges 0,l to 0,4. 0.25 max.Al N Roiled , R
15、 Shape in this area at manufacturers oDtion. q 09- Rokd W I- - 1 I Conforms to Il +I IS03353 I+ Recess in conformity with EN 3911 t- 1) When the length of the shank is less than one times the nominal value of the shank diameter O, the run-out is measured at a distance equal to half the actual shank
16、length. 2) For bolts having a shank length less than one times the nominal value of the shank diameter O, and for those threaded to head, the pitch diameter axis shall be used as the datum. Figure 1 Table 1 1 I In accordance with IS0 5855-2 R max. I min. O 5 0,3 =I=- 07105 - X 0,003 STD-AECMA PREN 3
17、912-ENGL 1797 W LO12311 00L328b 448 - Table 2 c Page 5 prEN 3912 : 1997 I 1) Mass = quoted in kg/l O00 parts I Page 6 prEN 3912 : 1997 4 Designation EXAMPLE : Description block Identity block EN391 2-0800&0 Number of this standard Thread code (see table 1) Length code (see table 2) Note : If necessary, the code 19005 shall be placed between the description block and the identity block. I 5 Marking EN 2424, style A, as indicated on figure 1. 6 Technical specification EN 3685 and EN 3905
