1、STD-AECMA PREN 3299-ENGL L997 LOL23LL DOL3Lb5 832 AECMA STANDARD prEN 3299 NORME AECMA Edition P 1 AECMA NORM July 1997 Edition approved for publication 1997-07-31 PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - B-1200 BRUXELLES - Tel. (+32i 2 775 81 1 O - Fax.
2、(+32) 2 775 81 11 Comments should be sent within six months after the date of publication to AECMA Gulledelle 94 C8 Chairman Mr Feltham B-1200 BRUXELLES ICs : 49.040.20 Descriptors : ENGLISH VERSION Aerospace series Shaft-nuts and threaded rings, self-locking, right- or left-hand MJ threads, in heat
3、 resisting steel FE-PA2601 (A286), silver plated Technical specification Srie arospatiale Luft- und Raumfahrt crous darbres et bagues filetes, freinage interne, filetage MJ droite ou gauche, en acier rsistant chaud FE-PA2601 (A2861, Wellenmuttern und Gewinderinge, selbstsichernd, Rechts- oder Links-
4、MJ-Gewinde, aus hochwarmfestem Stahl FE-PA2601 (A286). argents versilbert Spcification technique Technische Lieferbedingungen This “Aerospace Series “ Prestandard has been drawn up under the responsibility of AECMA (The European Association of Aerospace Industries). lt is published on green paper fo
5、r the needs 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
6、, physically 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
7、Standardization) for formal vote. STD-AECMA PREN 3299-ENGL 1777 = LO1231L OO13Lbb 779 Page 2 prEN 3299 : 1997 Contents list 1 Scope 2 Normative references 3 Definitions 4 Quality assurance 5 Requirements Annex A (normative) : Checking bearing surface perpendicularity Annex B (normative) : Method of
8、checking locking torque Annex C (normative) : Hardness test STD-AECMA PREN 3297-ENGL L777 W LO1231L 00131b7 b0.5 W Page 3 prEN 3299 : 1997 1 Scope This standard specifies the characteristics, qualification and acceptance requirements for self-locking shaft-nuts and threaded rings, with right- or lef
9、t-hand MJ threads, in FE-PA2601, silver plated, for aerospace applications. Temperature class : 450 OC 1) It is applicable whenever referenced. 2 Normative references IS0 3452 IS0 3534-1 977 IS0 4288 IS0 5855-2 IS0 6507-1 IS0 6508 EN 2786 EN 3042 ASTM E 11 2-88 Non-destructive testing - Penetrant in
10、spection - General principles Statistics - Vocabulary and symbols Rules and procedures for the measurement of surface roughness using stylus instruments Aerospace - MJ threads - Part 2 : Limit dimensions for bolts and nuts Metallic materials - Hardness test - Vickers test - Part 1 : HV 5 to HV 100 M
11、etallic materials - Hardness test - Rockwell test (scales A - B - C - D - E - F - G - H - K) Aerospace series - Electrolytic silver plating of fasteners 21 Aerospace Series - Quality assurance - EN aerospace products - Qualification procedure Standard Test Methods for Determining Average Grain Size
12、3) 3 Definitions For the purposes of this standard, the following definitions apply : 3.1 Finished nut or ring A nut or ring ready for use, inclusive of any possible treatment and / or surface coatings, as specified in the product standard or definition document 3.2 Definition document Document spec
13、ifying all the requirements for finished nuts or rings 1) Maximum test temperature of the parts 2) Published as AECMA Prestandard at the date of publication of this standard 3) Published by : American Society for Testing and Materials (ASTMI, 191 6, Race street, Philadelphia, PA 19103, USA STD-AECMA
14、 PREN 3277-ENGL $777 m LOL23LL 00131b8 541 m Page 4 prEN 3299 : 1997 3.3 Batch Quantity of finished nuts or rings, of the same type and same diameter, produced from a material obtained from the same melt, manufactured in the course of the same production cycle, heat treatment, surface treatment 3.4
15、Production cycle Period during which production proceeds without any voluntary or unforseen change in manufacturing parameters 3.5 Heat treatment cycle Period during which the oven continuously remains at nominal treatment temperature 3.6 Surface treatment cycle Period during which the surface treat
16、ment proceeds without any voluntary or unforseen change in surface treatment parameters 3.7 Discontinuities 3.7.1 Crack : rupture in the material which may extend in any direction and which may be intercrystalline or transcrystalline in character 3.7.2 Seam : open surface defect 3.7.3 Lap : surface
17、defect caused by folding over metal fins or sharp corners 3.7.4 particles may be isolated or arranged in strings. Inclusions : non-metallic particles originating from the material manufacturing process. These 3.8 Sampling plan A plan according to which one or more samples are taken in order to obtai
18、n information and possibly reach a decision 4) 3.9 Simple random sampling The taking of n items from a population of N items in such a way that all possible combinations of n items have the same probability of being chosen 4) 3.1 O Self-locking torque The torque to be applied to the nut or ring to m
19、aintain its movement of rotation in relation to the associated part, the assembly being under no axial load and the locking zone being completely engaged on the associated part (minimum protrusion of two pitches, including the end chamfer) 3.1 1 Breakaway torque The torque required to start unscrewi
20、ng the nut or ring with respect to the associated part, with the locking zone still fully engaged, but after the axial load in the assembly has been removed by unscrewing half a turn followed by a halt in rotational movement 4) Definition taken from IS0 3534 Page 5 prEN 3299 : 1997 3.12 Effective se
21、ating torque Part of the apparent seating torque which introduces or increases the axial load in the assembly. The effective seating torque is equal to the difference between the apparent seating torque and the self-locking torque. 3.13 Apparent seating torque The torque indicated by the dynamometri
22、c wrench when tightening 4 Quality assurance 4.1 Qualification EN 3042 Qualification inspections and tests (requirements, methods, numbers of nuts or rings) are specified in table 1. They shall be carried out on : - each type and diameter of nut or ring ; - 12 nuts or rings selected from a single ba
23、tch by simple random sampling. The test programme may possibly be reduced or the qualification be granted without inspection or testing : any such decision shall be based on the results obtained on similar diameters of nuts or rings, provided that the design and manufacturing conditions are identica
24、l. Table 2 indicates the allocation of nut or ring samples for the inspections and tests. 4.2 Acceptance 4.2.1 Purpose The purpose of acceptance inspections and tests is to check, as simply as possible, by a method representative of actual use conditions, with the uncertainty inherent to statistical
25、 sampling, that the nuts or rings constituting the batch satisfy the requirements of this standard. 4.2.2 Conditions Acceptance inspections and tests (requirements, methods, numbers of nuts or rings) are specified in table 1. They shall be carried out on each batch. Nuts or rings from the batch to b
26、e tested shall be selected by simple random sampling. Each nut or ring may be submitted to several inspections or tests. If a more stringent inspection is deemed necessary, all or part of the qualification inspections and tests may be performed during the acceptance inspection and testing. In this c
27、ase, the sample submitted to these inspections and tests is the same as that submitted for qualification inspection and tests. 4.2.3 Responsibility Acceptance inspections and tests shall be carried out by the manufacturer, or under his responsibility. STD-AECMA PREN 3297-ENGL 1997 m 1012311 OOL3170
28、LTT m Page 6 prEN 3299 : 1997 4.2.4 Inspection and test report A test report showing actual numerical values shall be provided if specified in the purchase order. 5 Requirements See table 1. Table 1 : Technical requirements and test methods Clause 5.1 5.2 5.3 5.3.1 - 5.3.2 continued Characteristic M
29、aterial Dimensions, tolerances of form and position Manufacturing Heat treatment Bearing surface Requirement In accordance with the product standard or definition document In accordance with the product standard or definition document The nuts or rings shall be manufactured by machining. The heat tr
30、eatment medium or atmosphere shall not cause any surface contamination except as permitted by 5.5.4. Solution treat (if applicable) at a temperature of 900 OC to 980 OC held at the selected temperature within f 15 OC for between 1 h min. and 2 h max. quench in oil, or alternative medium or faster. P
31、recipitation treat at 720 OC f 10 OC held at temperature for 16 h f 15 min cooled in air or faster process. Any scale not removed by subsequent machining shall be removed bv abrasive blastina. In accordance with the product standard or definition document. Standard gauging I A I Tab1e3 I Examination
32、 of the heat treatment equipment Examination of the heat treatment process Visual examination See annex A. I I Table3 I STD-AECMA PREN 3277-ENGL 1777 D 1012311 0013171 03b M Clause 5.3.3 i.3.4 i.3.5 - i.3.5.1 i.3.5.2 - i.3.5.3 i.4 - i.4.1 i.4.1.1 continued Characteristic rhreads and thread deformati
33、on Surface Pughness Surface :oating ippearance rhickness idhesion Ylechanical )roperties leusability :est Self -locking :orque at imbient :emperatwe 12 cycles) Page 7 prEN 3299 : 1997 Table 1 (continued) Requirement Threads in the locking region may be deformed in any manner provided that the nut or
34、 ring meets the requirements of this standard. The method of forming shall be indicated. Any tool marks shall blend smoothly without any abrupt changes. The finished nuts or rings shall allow the “GO“ thread plug or ring gauge to enter a minimum of 1,5 turns before engagement of the locking element.
35、 In accordance with the product standard or definition document In accordance with the product standard or definition document See 5.3.5. See 5.3.5. See 5.3.5. After testing, nut or ring threads shall not show any indications of distortion, galling or seizing as to prevent reassembly of the nut or r
36、ing freely, up to the self-locking zone. Threads of the inspection device shall remain serviceable and permit assembly of a new nut freely with the fingers up to the self-locking zone. The self-locking torque and the seating and unseating torque shall be measured for each cycle upon tightening and u
37、ntightening. They shall be within the min. I max. values given in table B. 1, columns 2 and 3 or 4, for each cycle. Inspection and test method OIA ) Visual examination Standard gauging A 9 Table 3 Table 3 IS0 4288 Visual examination See 5.3.5. lQl 9 I A I Table3 See 5.3.5. Inspection can be Q 3 carr
38、ied out at the same time A Table 3 as inspection per 5.5.1. See 5.3.5. Inspection can be O 3 carried out at the same time A Table 3 as insDection Der 5.4.1.3. STD-AECMA PREN 3277-ENGL 2997 = LO12322 0023172 T72 Page 8 prEN 3299 : 1997 Table 1 (continued) Clai i.4.1. i.4.1. 5.4.2 - 5.5 5.5.1 5.5.2 5.
39、5.3 continued Characteristic ;elf -locking torque at imbient temperature lone cycle) ielf-locking torque at imbient temperature ifter 450 OC saking Ifive cycles) Hardness Metallurgical woperties Vlicrostructure ;rain size Surface discontinuities before :eating) Requirement They shall be within the m
40、in. / max. values given in table B. 1, columns 2 and 3. They shall be within the min. / max. values given in table B.1, columns 2 and 3 or 4, for each cycle. 27 HRC to 37 HRC 280 HV 5 to 365 HV 5 Nuts or rings shall have a predominantly recrystallized microstructure. The inclusions shall not exceed
41、the values permitted in the materials technical specification. Grain size may vary according to section thickness and/or thread deformation, but shall, when compared with plate II of ASTM E 11 2, not be coarser than five. Isolated grains not exceeding a mean diameter 2, of 0,23 mm are acceptable. Cr
42、acks are not permitted. Open defects (seam) with less than or equal to 0,03 mm in depth are acceptable. Inspection and test method Q/A 1 Sample size See annex B. A Table 3 See annex C. characteristics of the Microscopic examination at a magnification of 100 times A Table 3 IS0 3452 Q 3 A Table 3 Sam
43、ples showing indications which are considered significant shall be subjected to a microscopic examination at a suitable magnification (e.g. 1 O0 times). STD*AECMA PREN 3277-ENGL 3777 = 10123Ll 0033373 707 Page 9 prEN 3299 : 1997 Characteristic Table 1 (concluded) Requirement Clause 5.5.4 5.5.5 5.6 5
44、.7 5.8 Surface contamination Depth of oxide penetration to 0.01 mm is permissible except on threads and surface bearing. Material identification Finished nuts or rings shall be subjected to a non-destructive test to verify the type of material. Product identification Packaging Marking in accordance
45、with the product standard or definition document The nuts or rings shall be individually packed in such a way as to prevent any damage or corrosion occurring in the course of handling, transportation and storage. Each basic package shall only contain nuts or rings with the same part number and of th
46、e same batch number. Labelling Each basic package shall bear a label upon which is legibly recorded : - designation as specified by the product standard or definition document ; - quantity ; - batch number ; - manufacturers name and trade mark. Inspection and test method See 5.5.1, The test equipmen
47、t shall be calibrated by samples of known chemical composition of the same type and form and in the same heat treatment and surface coating condition as the nuts or rings to be tested. Visual examination Visual examination Visual examination 1) Q = Qualification, A = Acceptance 2) Mean diameter = th
48、e average of the major and minor axes of an individual grain Q/A I Sample ski Table 3 qz STDmAECMA PREN 3279-ENGL 1797 W LO123L1 0013174 845 W Page 10 prEN 3299 : 1997 Table 2 : Allocation of qualification testing requirements Type of test 1) Tests may be carried out on samples 1 to 3 or on samples
49、4 to 6 (see annex C). I STD-AECMA PREN 3299-ENGL 1777 1012311 0013175 781 W Page 11 prEN 3299 : 1997 Characteristic Surface coating - Appearance Table 3 : Sampling plan for inspections and acceptance tests Paragraph 5.3.5.1 Packaging Labelling Dimensions - Tolerances Material identification I 5.7 5.8 5.2 5.5.5 Reusability - one cycle at ambient temperature Surface roughness Product identification I 5.4.1.2 5.3.4 5.6 Surface coating - Thickness - Adhesion Hardness Microstructure Grain size Surface discontinuities 5.3.5.2 5.3.5.3 5.4.2 5.5.1 5.5.2 5.5.3 I Bearina sur
