1、STD-AECMA PREN 3725-ENGL 3777 30323LL 0033252 Ob5 m Edition approved for publication 1997-07-31 AECMA STANDARD NORME AECMA AECMA NORM C8 Chairman Mr Feltham Comments should be sent within six months after the date of publication to AECMA Gulledelle 94 6-1 200 BRUXELLES prEN 3725 Edition P 1 July 199
2、7 PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - 6-1200 BRUXELLES - Tel. 1+32) 2 775 81 10 - Fax. (+32) 2 775 81 11 ICs : 49.040.20 Descriptors : ENGLISH VERSION Aerospace series Bolts, pan head, six lobe recess, normal shank, long thread, in titanium alloy TI-
3、P63, MOS, coated Classification : 1 100 MPa (at ambient temperature) Srie arospatiale Vis tte cylindrique, empreinte six lobes, tige normale, filetage long, en alliage de titane TI-P63, revtues MOS, Classification : 1 100 MPa ( temprature ambiante) Luft- und Raumfahrt Zylinderschrauben, Sechs-Bogenz
4、ahn, Innenantneb, langes Gewinde, aus Titanlegierung, MOS, beschichtet Klasse : 1 100 MPa (bei Raumternperatur) 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
5、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, physically or
6、 functionally, without re-identification of the standard. After examination and signature of the AECMA Standard Checking Centre (NPSI 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
7、) for formal vote. aecma 1997 STD-AECMA PREN 3725-ENGL 1997 W lOL23LL 0033253 TTL I Page 3 prEN 3725 : 1997 1 Scope This standard specifies the characteristics of pan head bolts with six lobe recess, normal shank and long thread, in TI-P63, MOS, coated, for aerospace applications. Strength class : 1
8、 100 MPa 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 2424 Aerospace - Rolled threads for bolts - Lead and runout requirements Aerospace - MJ threads - P
9、art 2 : Limit dimensions for bolts and nuts Aerospace series - Marking of aerospace products EN 2491 Aerospace series - Molybdenum disulphide dry lubricants - Coating methods 2, EN 3457 Aerospace series - Titanium alloy TI-P3 - Not heat treated - Reference heat treatment : solution treated and aged
10、- Grade 2 forging stock for fasteners - D 5 25 mm 3, EN 3813 Aerospace series - Titanium alloy TI-P63 - R, L 1 1 O0 MPa - Wire for forged bolts - s 15 mm 4) EN 381 8 Aerospace series - Bolts with MJ threads, in titanium alloy TI-P3 - Classification : 1 100 MPa (at ambient temperature) - Technical sp
11、ecification 3, EN 3905 EN 391 1 Aerospace series - Six lobe recesses for bolts - Technical specification 3, Aerospace series - Six lobe recess - Geometrical definition 3, 3 Required characteristics 3.1 Configuration - Dimensions - Tolerances See figure 1 and tables 1 and 2. Dimensions and tolerances
12、 are in millimetres. They apply before MOS, coating. 3.2 Materials EN 3457 or EN 381 3 3.3 Surface treatment EN 2491 1) Minimum tensile strength of the material at ambient temperature 2) Published as AECMA Standard at the date of publication of this standard 3) Published as AECMA Prestandard at the
13、date of publication of this standard 4) In preparation at the date of publication of this standard Previous page is blank STD-AECMA PREN 3725-ENGL 1997 W LOL23LL 0013254 738 m Page 4 prEN 3725 : 1997 Thread ) Code Designation “I/ o+ oy OYE, Values apply before Mos2 coating. DEFGHKQ R X Y Z Recess O
14、h12 max. min. min. + 0,2 h15 f 0.5 max. min. Remove sharp edges 0,l to 0,4. 030 MJ30,5-4h6h 3 5,5 5,l 0,3 1,15 2,2 2,3 o,4 o,2 050 MJ50.8-4h6h 5 8,5 8,l 1,8 4 385 Or5 Of3 060 MJGxl-4h6h 6 10 9,5 2.25 4,7 4,2 080 MJ81-4h6h 8 13 12,4 1,5 2,7 6 6,2 040 MJ4xOf7-4h6h 4 7 6,6 o,7 1,3 3 3,l 070 MJ71-4h6h 7
15、 12 11,4 2,5 5,4 5.2 0,7 0.5 O 0,ll EN 391 1-10 0,14 EN 391 1-25 0,003 0,18 EN 391 1-27 0,21 EN 391 1-30 0.25 EN 391 1-40 0,28 EN 391 1-45 0,12 0,15 Recess in conformity with EN 3911 I Markinq Roiled I - 0.8 r- Shape in this area at IS0 3353 to t-u- 1) When the length of the shank is less than one t
16、imes the nominal value of the shank diameter D, the run-out is measured at a distance equal to half the actual shank length. 2) For bolts having a shank length less than one times the nominal value of the shank diameter D, and for those threaded to head, the pitch diameter axis shall be used as the
17、datum. Figure 1 Table 1 STD-AECMA PREN 3725-ENGL 1777 B 2012311 0023255 874 Page 5 prEN 3725 : 1997 Page 6 prEN 3725 : 1997 STD-AECMA PREN 3725-ENGL 1997 1OL23LL 0033257 b47 Thread code Page 7 prEN 3725 : 1997 4 Designation EXAMPLE : Description block Identity block EN3725-080Q Number of this standa
18、rd 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. 5 Marking EN 2424, see table 3 and as indicated on figure 1. Table 3 I 030 to 050 I C I I A I 060 to 080 I 6 Technical specification EN 3818 and EN 3905
