1、British Standard A 297 : 1987 IS0 79941985 UDC 621.882.216.5:629.7 0 British Standards Institution. No part of this publication may be photocopied or othetwise reproduced without the prior permission in writing of BSI British Standard Aerospace Series : Specification for Internal drive, offset cruci
2、form recess (Torq-Set) for rotary fastening devices. Metric series IS0 title: Aerospace - Internal drive, offset cruciform recess (Torq-Set 1 for rotary fastening devices - Metric series Srie arospatiale. Empreinte cruciforme dporte dentrainement intrieur (Torq-Set) pour dispositifs de fixation. Sri
3、e mtrique - Spcifications Luft- und Raumfahrt-Reihe. Mechanische Verbindungselemente mit I nnenantrieb und FIgeIkreuzschIitz (Torq-Set). Metrische Reihe Contents National foreword Committees responsible Specification O. Introduction I. Scope 2. Field of application 3. References 4. Definitions 5. Ch
4、aracteristics 6. Designation Tables 1. Recess - General dimensions 0 2. Recess dimensions applicable to 100 o countersunk normal and reduced head Page 1 Back page 4 5 3. Recess dimensions applicable to normal flat top pan head 4. Recess gauge - Dimensions 5. Recess penetration gauge - Dimensions 6.
5、Driver - Dimensions Figures 1. Recess -Configuration 2. Recess in 100 o countersunk head 3. Recess in normal flat top pan head 4. Recess gauge - Configuration 5. Recess penetration gauge - Configuration 6. Driver - Configuration Page 6 8 10 11 4 5 6 7 9 11 National foreword This British Standard, wh
6、ich has been prepared under the direction of the Aerospace Standards Committee, is identical with IS0 7994-1985 Aerospace - Internal drive, offset cruciform recess (Torq-SetQ) for rotary fastening devices - Metric series published by the international Organization for Standardization (ISO. Terminolo
7、gy and conventions. The text of the international standard has been approved as suitable for publication as a British Standard without deviation. Some terminology and certain conventions are not identical with those used in British Standards; attention is drawn especially to the foliowing. The comma
8、 has been used as a decimal marker. In British Standards it is current practice to use a full point on the baseline as the decimal marker. Wherever the words International Standard appear referring to this standard, they should be read as British Standard. . British Standards Institution BSI Ar297 8
9、7 = 3b24bb O083293 4 1 s f * British Standard A 297 : 1987 Cross-references International standard Corresponding British Standard IS0 128-1982 BS 308 Engineering drawing practice Part 1 : 1984 Recommendations for general principles (Technically equivalent) Part 3 : 1972 Geometrical tolerancing (Tech
10、nically equivalent) IS0 1101-1983 Attention is drawn to the fact that it is claimed that the Internal drive, offset cruciform recess (Torq-Set) for rotary fastening devices is the subject of British patent No. 1 473 969 copies of which can be obtained from the Patent Office, 25 Southampton Buildings
11、, London WC2A IAY. BSI takes no position as to the validity of the patent or whether it is still in force. The patent is irrevocably endorsed licences of right under Section 46 of the Patents Act 1977, which states: (a) any person shall, at any time after the entry is made, be entitled as of right t
12、o a licence under the patent on such terms as may be settled by agreement or, in default of agreement, by the Comptroller on the application of the proprietor of the patent or the person requiring the licence. (3) Where such an entry is made in respect of a patent - Licence details may be obtained f
13、rom the registered proprietor of the patent. Compliance with a British Standard does not of itself confer immunity from legal obligations. O Introduction Users of this International Standard are advised that the in- ternal drive recess specified in this International Standard is the Torq-Set recess
14、and that trademark and proprietary rights applyl). Patent holders have agreed to negotiate licences on terms and conditions defined in statements that are available on request from the IS0 Central Secretariat. 1 Scope This International Standard specifies maximum and minimum dimensional requirements
15、 for an internal drive recess configura- tion for rotary fastening devices, and for the associated drivers and gauges, for metric design. The combinations suggested herein are provided for metric shank diameters. 2 Field of application This configuration is intended primarily for use in aerospace ap
16、- plications and other critical areas where high assembly and removal torque capabilities are required. 3 References IS0 128, Technical drawings - General principles of presenta- tion. IS0 1101, Technical drawings - Geometrical tolerancing - Tolerancing of form, orientation, location and run-out - G
17、eneralities, definitions, symbols, indications on drawings. 4 Definitions 4.1 internal drive recess: A formed indentation in the centre of the head of the fastener, with a main axis extending along the longitudinal centreline of the part, the function of which is to accept a closely fitting driving
18、tool for the trans- mission of rotary movement. 4.2 driver: A co-operating tool for use with a fastener the form of which matches the indentation in the head of the fastener to provide a coupling between a rotary driving force and the head of the fastener. 1) Torq-Set and ACRO are registered tradema
19、rks of the Phillips Screw Company. 4.3 offset cruciform recess: An internal drive recess of an offset cruciform configuration having four equally spaced radial grooves, the sides of which are parallel to each other and parallel to the axis of the fastener. The clockwise (driving) sides are arranged
20、on 90 radial planes 0 and taper from a maximum diameter at the head surface to a minimum diameter below the the head surface. 4.4 anticamout rib (ACRQ) : A projection of a small cross- section of material extending along a removal counter- clockwise) recess wall and generally parallel to the recess
21、axis. This rib is provided to allow preliminary indentation by the driver projections upon the application of a counter-clockwise torque and resist the tendency for the driver to ride up and out (self-eject) of the recess. Drivers are also provided with projections along the removal walls which exte
22、nd 90 to the axis in order to indent properly the recess projections upon application of a counter-clockwise torque. 2 i i.- i British Standard A 297 : 1987 5 Characteristics O 5.1 form as follows : The configuration, dimensions and tolerances shall con- - recess : in accordance with figures 1,2 and
23、 3 and tables 1, 2 and 3; - recess gauge configuration : in accordance with figure 4 and table 4; - assembly of the recess gauge: in accordance with figure 5 and table 5; - driver tip: in accordance with figure 6 and table 6. 5.2 The presentation of the figures conforms with IS0 128 and the symbols
24、for tolerances of form and position are in ac- cordance with IS0 1101. 5.3 check the recess. These gauges are as follows : Figure 4 and table 4 deal with the various gauges used to - Type A GO gauge: used to measure the recess cavity at maximum material condition and to measure gauge pen- etration v
25、alues as given in tables2 and 3; this gauge can also be mounted in a holder and used with a dial indicator, as indicated in figure 5 and table 5. - Type B GO gauge: used to limit interference between the recess rib and the driver; this gauge is used by hand, as it is, without a dial indicator. - Typ
26、e C NOT GO gauge: limits the minimum material condition of the recess; this gauge is used by hand, as it is, without a dial indicator. 6 Designation A driving recess complying with this International Standard shall be designated as follows : Driving recess IS0 7994- R XX 3 I BSI A*297 87 m lb24bb 00
27、83293 8 m Recess size E“ F and No. max. min. max. min. 0,46 0,41 R1.6 R2 British Standard A 297 : 1987 I Inch ano max. min. max. min. may. min. No.* R I VI _ .- J 0.94 0,84 O 1 1,12 1,02 0,25 0,OO O 4 a O + O O cn D-D * See tables 2 and 3 $111 For all head configurations Z Figure 1 - Recess - Config
28、uration Table 1 - Recess - General dimensions Dimensions and tolerances in millimetres I I R2,5 0.53 0,46 1.50 1,40 R3 0,58 0,51 1.70 1.60 0,46 0,20 0,648 0,622 0,74 0.66 2,08 1.98 R3.5 R4 I 0,775 I 0,749 I 0.86 I 0.79 I 2.44 I 2,34 I 0,76 I 0,41 0,902 0,876 0.99 0.91 2,82 2.72 R5 R6 1,206 1,181 1.3
29、0 1.22 3,73 3.63 1,537 1,511 1.63 1,55 4,67 4,57 RE R10 1.93 1.85 5.59 5.49 1.02 0.58 1,32 0,79 1) Recess sizes R3.5 to R8 are to have ACRO ribs on the removal wall of each of the four win1 shape; the crest of the triangle is defined by dimension E. The rib should, preferably, be within the and be o
30、n at least the lower 75 % of the wall. 2) For information and comparison purposes only. . The rib is preferred to be generally triangular in nvelope shown by the diameter V, rnax. and min., 4 British Standard A 297 : 1987 M5 M6 M7 M8 M10 M12 M14 Figure 2 - Recess in lo countersunk head R5 R4 R6 R5 R
31、6 R8 R10 R12 R14 Table 2 - Recess dimensions applicable to 100 countersunk normal and reduced head 9,07 10,85 14,43 16,21 17,98 Dimensions in millimetres 8,81 3.10 2,84 2,184 1,778 10.59 3.68 3.43 2,616 2,159 14,17 4,90 4,65 3,493 2,934 15.95 5.51 5,26 3,924 3,315 17.73 6.12 537 4,343 3,683 Nomina s
32、hank I Recess and driver No. I R18 R22 R24 or thread diameter Normal head Reduced head 21,56 21,31 7.32 7,06 5,232 4,470 25,12 24.87 8.53 8.28 6,083 5,220 28,70 28.45 9.73 9.47 6,960 5,994 M3,5 R3,5 M4 I R4 I I M16 I R16 I I M22 R22 M24 I R24 I I Gauge I and Recess driver IHIJl penetration I No. I m
33、ax. I min. I may. I min. I max. I min. 6,30 I 6,05 1.40 1,14 I 2,29 I 2,03 I R6 I 8,26 I 8.00 I 3,00 I 2.74 I 2,261 I 1,905 R14 R16 5 British Standard A 297 : 1987 Nomina Recess H 1 or?%d 1 1 diameter max. I min Figure 3 - Recess in normal flat top pan head Gauge penetration J max. I min. max. I min
34、. Table 3 - Recess dimensions applicable to normal flat top pan head M2.5 M3 M3.5 M4 Dimensions in millimetres R2,5 3,545 3,30 1,35 1 ,o9 1,029 0,787 R3 3,99 3,73 1 ,= 1,24 1,143 0,889 R3,5 4,s 4.65 1 ,= 1,57 1,410 1,143 R4 5,79 534 2,16 1,91 1,676 1,384 M10 i R10 M12 R12 M14 RI4 M16 R16 I M1.6 I R1
35、,6 I 2,21 I 1,96 I 0,84 I 0,58 I 0,635 I 0,432 I 11,61 11.35 4,09 3.84 2,997 2,540 14,43 14,17 4,90 4,65 3,493 2,934 1621 15,95 5,51 526 3,924 3,315 17.98 17,73 6,12 5,87 4,343 3,683 I M2 I R2 I 2,64 I 23 I 0.99 I 0,74 I 0,762 I 0.546 I M24 R24 28,70 I 28,45 I 9,73 1 9,47 I 6,960 I . 5,994 M5 i R5 I
36、 6,68 I 6,43 I 2,49 I 2,24 I 1,930 I 1,613 M6 I R6 I 8,76 I 8,51 I 3.25 I 3,00 I 2,515 I 2,159 I M7 I R6 I 8,76 I 8,51 I 325 I 3.00 I 2,515 I 2,159 I I M20 I R18 I 21.56 I 21,31 I 7,32 1 7,06 I 5,232 1 4,470 I I M22 I R22 I 25,12 I 24,87 I 8,53 I 828 I 6,080 I 5,220 I Align within wt BSI A*Z97- 87 0
37、 3b246bT 008L2q.6=- British Standard A 297 : 1987 Dimensions and tolerance in millimetres Material : Heat-treatable corrosion-resistant steel. Heat treat: 58 to 62 HRC. O Al1.4 to 12,7 -89,5 to 90“ Figure 4 - Recess gauge - Configuration 7 BSI Ast297 87 3b24bb9 0083297 5 W I R1,6A GO R1,6C NO GO R2A
38、 GO R2C NO GO R2,5A GO R2,5C j NO GO 0,97 0,810 0,404 0,917 0,457 0,810 0,404 0,lO 0,917 0,457 0,912 0,455 1,069 0,533 1,14 1,52 R3A R3C R3,5A21 R3,5B2 GO 1,013 NO GO 1,171 I GO i ,318 0,15 0,658 1 2,11 GO 1,245 I 0,622 I 2,11 R3,5C2 I NO GO 1,476 I 1,295 1,547 1,511 1,626 5,74 4,72 4,72 7,16 R6C21
39、R8A2i R8B21 R8C21 NO GO 2,593 GO 3,096 GO 3,023 NO GO 3.254 2,41 2,92 I 5/i6A 2,41 2,92 5/16c R18A R18C R22A R22C R24A R24C GO 7,516 NO GO 7,724 GO 8.786 NO GO 8,994 GO 10,056 NO GO 10,264 British Standard A 297 : 1987 O Table 4 - Recess gauge - Dimensions Dimensions and tolerances in millimetres R
40、max. 0,13 3A I 3c 6,35 1 1 I 4A 0,505 M 1173 1 1 4c I 0,76 I 1,27 I 6A 6B 11,13 0,76 1,27 6C 0,737 * 1 ,o2 1,52 I 8A 6,35 I 0,749 I 2.46 ac 1 OA 0,912 1,753 0,876 2,84 NO GO 1,984 0,991 4,55 6,35 10b 1 oc 1 1,217 I 3,76 1113 t-+”- 23.22 I 1.78 I 2.29 I 1/4C 0.76 R1OA 1 GO I 2,706 I I I 318 11,13 I J
41、%C 1,852 1,930 5164 R1OC I NO GO I 3,863 I I l+l 7,47 I V2A R12C NO GO I 5,184 I I 1/2c I I I 1 1 2,817 2,921 3.226 1 1 I %A R16A 6,246 I R16C I NO GO I 6,454 I 1 ,o2 3,861 12,98 I .OA %,IO I 1.oc 14,81 1) Mark gauge with International Standard number, recess gauge number and the type of gauge. 2) T
42、he removal wall of each of the two wings on types A and C recess gauge numbers R3,5 to R8 contains grooves as shown to clear ACW rib. 3) For information and comparison purposes only. British Standard A 297 : 1987 Dimensions and tolerances in millimetres Gauge assembly NOTE - Same as inch penetration
43、 gauge except for dial indicator. Collar Spring: HT , Material: Steel spring wire Wire: O, Size: 67/32 x 25,4 long Ends squared by U my O grinding Gauge point assembly Gauge body Collar Figure 5 - Recess penetration gauge - Configuration 9 Recess penetration gauge No. A +0,013 O BSI A8297 87 E Lb24b
44、b C108L299 9 I - w British Standard A 297 1 1987 Table 5 - Recess penetration gauge - Dimensions Dimensions and tolerances in millimetres 0 B f0,41 C f0.41 D fO,41 J i 0,41 - 22,23 - 31.75 1 + 0,03 0 - 9,5 - 19,05 M t 0,4 - 3,18 - 6,35 - 3,18 P f0,13 - 12,95 - 20.32 N R f 0,41 5 f0.41 - - 3,18 +0,01
45、3 0 R1,6 R2 R2.5 2.21 21,44 - 18,26 R3 4.78 - 7,92 - 1,07 I 1,04 I 3,33 I 0,79 12,70 9,s 9,500 19,025 R3,5 1,37 I 1,35 I 4,06 I R4 R5 R6 - 1.57 3.15 I 3.12 I 9.07 I RE R10 R12 -1 3,76 3,73 10,85 1,57 5.03 5.00 14.43 19,025 U14 R16 R18 R22 28,550 15,88 2159 - 3,18 - 6,35 - 28,550 U24 10,ll 10.08 28,7
46、0 1 For information and comparison purposes only. 10 IO Y 20“ to ,I / Minimum - straight. cut British Standard A 297 : 1987 Dimensions and tolerances in millimetres Run-out at manufacturers option Figure 6 - Driver - Configuration Table 6 - Driver - Dimensions Dimensions and tolerance in millimetres
47、 J R I S I W11 F G over rib D may. I min. may. 1 min. l*l I I 0,406 I 0,394 151 1.17 1,19 I 0,13 min. I (degrees1 O 93,5 92.5 1,27 91.5 rnax. 0.38 0,76 1) Drivers for recess and driver sizes R3.5 to. R8 are fo have the ACR“ ribs on the removal wall of each of the four wings. The rib is preferred to
48、be generally triangular in shape, having base, height and location dimensions which fall within the envelope of the minimum/maximum dimension as shown. Wing thickness to be measured over ribs. 2) . For information and comparison purposes only. Publications referred to See national foreword. 11 - BSI
49、 A8297 87 I Lb24bb OOB13OL 3 M i-, c L British Standard IS0 7994-1 985 A 297 : 1987 Amd. No. Date of issue This British Standard, having been prepared under the direction of the Aerospace Standards Committee, was published under the authority of the Board of BSI and comes into effect on 31 March 1987. O British Standards Institution, 1987 ISBN O 580 15841 1 British Standards Institution Incorporated by Royal Charter, BSI IS the independent national body for the preparation of British Standards. It is the U
