1、A MER CAN STANDARD Miniature ASA B18.11-1961 REAFFIRMED 1983 UDC 621.882 REAFFIRMED 2000 FOR CURRENT COMMITTEE PERSONNEL PLEASE SEE ASME MANUAL AS-11 onjorj Society of Automotive Engineers Screws The American Society of Mechanical Engineers THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS United Enginee
2、ring Center 345 East 47th Street New York, N. Y. 10017 ACCEPTANCE NOTICE ANSI 618.11-1961 7 April 1971 The following Industry Standardization Document was adopted on 7 April 1971 for mandatory use by the Department of Defense. The indicated industry group has furnished the clearances required by exi
3、sting regula tions. Copies of this document are stocked by the DOD Single Stock Point. Nava! Publications and Forms Cen ter. Philadelphia. Pennsylvania 19120. for iSSue to Military Activities and Federal Agencies only. Title of Document: Miniature Screws Document No.: ANSI B18.111961 Date of Adopted
4、 Issue: 1961 Releasing Industry Group: The American Society of Mechanical Engineers Custodians: Military Coordinating Activity: Army - we Army - we Navy - SH Air Force - 82 Reviewer Activjties Army - AT. AV, MU Navy - None A ir Force - None Project No. 5305.1097 I FSC 5305 No part of this document m
5、ay be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. Copyight 1961, by THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS Printed in U.S.A. Reprinted March 1972 Foreword MINIATURE screws, as covered by this standard. are those
6、 having threads of a nominal“diam eter from 0.0118 inch (0.3 mm) to 0.0551 inch (1.4 mm). Demand for screws and threads of such sizes has extended in recent years from the needs of the watch industry to subminiaruriza tion requirements of concrol mechanisms, instrumeors, and other devices. This led
7、to the devlop-. ment of Unified Miniature Screw Theea“ds, ASA B1.1O-1958. This is the complement to the screw thread standard to provide a recommended series of miniature screws and nuts. Subcommittee 13 of Sectional Committee B 18 first undeitook development of a product standard for -miniature scr
8、ews which was submitted 0 letter ballot of the Sectional Committee February 9, 1960. Final approval as an American Standard was given on February 20, 1961. Standards for nuts are in process of development. Officers of Sectional Committee H. W. Robb, Chairman, Engineering Services, General Electric C
9、o., 1 River Road, Schenectady 5, New York F. V. Kupchak, Vice Chairman, Westinghouse Electric Corp., Standards Department 2F, East Pittsburgh, Penna. R. B. Belford, Secretary. Technical Advisor, Industrial Fasteners Institute, 1517 Terminal Tower, Cleveland 13, Ohio Personnel of Subcommittee No. 13
10、00 Mioiature Screws M. A. Schultheis, Chairman, Staff Engineer, Engineering Standards, Building 6, Mail Station T2057, Hughes Aircraft Co., Culver City, Calif. J. C. Burgbacher, Watch Enginp.er, Bulova Watch Company. Inc . Bulova Park, Flushing 70, N. Y. J. B. Dirlam, J. I. Morris Company, 394 Elm S
11、treet, Southbridge, Mass. E. W. Drescher, Bulova Watch Company, Inc., 7520 Astoria Blvd., Flushing 70, N. Y. F. L. Calkins, Liaison, Wright Air Development Div., Standardization Section, Attn: WWDXSS, U.rightPatterson AFB, Ohio L H. Fullmer, Chief, Engineering Metrology Section, National Bureau of S
12、tandards, Washington 25, D. C. M. C. Kunz, Weston Electrical Instrument Corp., 614 Freylinghuysen Avenue, Newark, N. J. F. V. Kupchak, Westinghouse Electric Corp., Standards Department 2-F, East Pittsburgh, Pa. Vincent Meigs, Autonetics, A Division of North American Aviation, Inc., 9150 E. Imperial
13、Highway, Downey, C aliL R. L. Rufsuyder, Senior Design Engineer, Oldsmobile Motor Div., General Motors Corp . Lansing, Mich. E. H. Schaeffer, Chief Manufacturing Engineer, Elgin National Watth Co., agin, Illinois C. E. Smart, Works Manager, W. J.I . lliUJ ,0; TO MINOR 45. 5 D“ MIN Table 1 - Filli.te
14、r Head Fillister Head Dimensions H J T (b) C Inch Dia Head Dia Head Hgt Slot Width Slot Depth Chamfer Max Max Min Max Min Max Min Max Min Max 318 0.0118 0.021 0.019 0.012 0.010 0.004 0.003 0.006 0.004 0.002 282 0.0138 0.023 0.021 0.014 0.012 0.004 0.003 0.007 0.005 0.002 254 0.0157 0.025 0.023 0.016
15、 0.013 0.005 0.003 0.008 0.006 0.002 254 0.0177 0.029 0.027 O.OIB 0.015 0.005 0.003 0.009 0.007 0.002 203 0.0197 0.033 0.031 0.020 0.017 0.006 0.004 0.010 0.007 0.003 203 0.0217 0.037 0.035 0.022 0.019 0.006 0.004 0.011 0.008 0.003 169 0.0236 0.041 0.039 0.025 0.021 0.008 0.005 0.012 0.009 0.004 145
16、 0.0276 0.045 0.043 0.028 0.02. O.OOB 0.005 0.014 0.011 0.00. 127 0.0315 0.051 0.049 0.032 0.028 0.010 0.007 0.016 0.012 0.005 113 0.0354 0.056 0.054 0.036 0.032 0.010 0.007 0.018 0.014 0.005 102 0.0394 0.062 0.058 0.040 0.035 0.012 0.008 0.020 0.016 0.006 102 0.0433 0.072 0.06B 0.045 0.040 0.012 0.
17、008 0.022 0.018 0.006 102 0.0472 0.082 0.078 I 0.050 0.045 0.016 0.012 0.025 0.020 0.008 B5 0.0551 0.092 O.OBB 0.055 0.050 0.016 0.012 0.028 0.023 0.008 R (e) Radius Max 0.002 0.002 0.002 0.002 0.002 0.002 0.003 0.003 0.004 0.004 0.005 0.005 0.006 0.006 (II) Bold (ace type indicate! preferred size (
18、b) lOT“ measured from bearing surface (e) Relative to max. major dill MATERIAL, CORROSION RESIST ANT STEELS, ASTM Designation 1.276 MACHINE FINISH: APPLIED COATINGS, NOTE: CLASS 303, COND A CLASS 416, COND A, HEAT TREAT TO APPROX 120,000-150,000 PSI (ROCKWELL C2B-34) CLASS 420, COND A, HEAT TREAT TO
19、 APPROX 220,000-240,000 PSI (ROCKWELL 00-53) BRASS: TEMPER HALF HARD ASTM Designation B16 NICKEL SILVER: TEMPER HARD ASTM Designation 6151, Alloy C Machined surface roughness of beads shall b approximately 63MU in. arithmetical average determined by visual comparison. CORROSION RESIST ANT STEEL: Pas
20、sivate BRASS: Bare, Black Oxide or Nickel Flash. NICK EL SILVER: None 1. The diameter of the unthreaded body shall not be more than the maximum major diameter nor tess than the minimum pitch diameter of the thread. 2. Fat screw lengths fot times the maior diameter or less, thread lengc.h(U) shall e&
21、tend to within two threads of the head bearing surface. Screws of greaxer length shall have complete threads for a minimum of four major diameters. 3. Screws shall be free of all projecting burrs, observed at 3X magnification. 4. All dimensions are in inches. 6 Size D Desig-Thd, Basic nation p“ Majo
22、r (a) Incb Dia Max 30 UNM 318 ! 0.0118 35 UNM 282 100138 40 UNM 254 10.0157 45 UNM 254 0.0177 SO UNM 203 i 0.0197 )5 UNM I 203 0.0217 60 UNM 169 0.0236 70 UNM I 145 0.0276 80 UNM 127 0.0315 90 UNM 113 0.0354 100 UNM 102 0.0394 110 UNM 102 0.0433 120 UNM 102 0.0472 140 UNM 85 0.0551 , SLOTTED HEAD MI
23、NIATURE SCREWS -*-L- R Table 2 Pan Head -UNM THREAD ASA 81.10 Pan Head Dimensions A B J T (b) Head Dia Head Hgt Slot Width Slot Depth Max Min Max Min Max Min Max Min 0.025 0.023 0.010 0.008 0.005 0.003 0.005 0.003 0.029 0.027 O.Oll 0.009 1000) 0.003 0.006 0.004 0.033 0.031 0.012 0.010 0.006 0.004 0.
24、006 0.0Q.4 0.037 0.035 0.014 0.012 10.006 I 0.004 0.007 0.005 0.041 0.039 0.016 0.013 10.008 0.005 0.008 0.006 0.045 0.043 O.OIS 0.015 0.008 0.005 0.009 0.007 I 0.051 0.Q.49 0.020 0.017 0.010 0.007 0.010 0.007 0.056 0.0)4 0.022 0.019 I 0.010 0.007 0.011 o.ooS 0.062 0.058 0.025 0.021 0.012 0.008 0.01
25、2 0.009 0.072 0.0681 0.028 0.024 0.012 0.008 0.014 O.Oll 0.OS2 0.078 I 0.032 0.028 0.016 0.012 0.018 0.014 0.092 0.08S 0.0)6 0.032 0.016 0.012 0.018 0.014 0.103 0.097 I 0.040 0.035 0.020 0.015 0.020 0.016 0.113 0.107 i 0.045 0.040 0.020 0.015 0.022 0.018 -C R (c) Chamfer Radius Max Max 0.002 0.002 0
26、.002 I 0.002 0.002 0.002 0.002 0.002 0.003 0.002 0.003 0.002 0.004 0.003 0.004 0.003 0.005 0.004 0.00) 0.004 0.006 0.005 0.006 0.005 O.OOS 0.006 0.008 0.006 (n) Bold face type indir:ates pre Cured size (b) “T“ measured from bearing surface (e) Relative to mall:. major dis MATERIAL: CORROSION RESIST
27、ANT STEELS: ASTM Designation A276 CLASS 303, COND A CLASS 416, CONO A, HEAT TREAT TO APPROX 120,000-150,000 PSI (ROCKWELL C28-341 CLASS 420, COND A, HEAT TREAT TO APPROX 220,000-240,000 PSI (ROCKWELL 00-531 BRASS: TEMPER HALF HARD ASTM Designation 816 NICKEL SILVER: TEMPER HARD ASTM Designation B151
28、. Alloy C MAQ-iINE Machined surface roughness of heads shall be approximately 63MU in. arithmetical average FINISH: determmed by viS1lal comparison. APPLIED CORROSION RESISTANT STEEL: Passivate. COATINGS: BRASS: Bace, Black Oxide or Nid:.el Flash. NICKEL SILVER: None NOTE: 1. The diameter of the un
29、threaded body shall not be more than the maximum major diameter nor less than the minimum pitch diameter of the thread. 2. For screw lengths four times the major diameter or less. thread length (Lt) shall extend to with in twO threads of the head bearing surface. Screws of reate.r length shall have
30、complete threads for a minimum of four major diameters. 3. Screws shall be free of all projecting burrs, ubserved at 3X magnification. 4. All dimensions are in inches. 7 AMERICAN STANDARD Io-L-R UN“ THREAD ASA SUO Table 3 - lOO-Dog Flat Head D Head Dimensions Siza. Thds Basic Av (b) Desig- pe, Major
31、 A Dia of H J nation loch Dia Head Dia Full Cone Head Hgt Slot Width Slot (a) Ma. M Min At Max H Max Min Max Min Max 30 UNM 318 0.0118 0.023 0.021 0.0285 0.007 0.005 O.OIU 0.003 O.OIU 35 l1I1 _2!2 -Q,H,a 1l.025 0.023 0.0305 0.007 0.005 0.004 0.003 0.004 40 UNM 254 0.0157 0.029 0.027 0.0348 0.008 0.0
32、06 0.005 0.003 0.005 45 UNM 254 0.0177 0.033 0.031 0.0392 0.009 0.007 0.005 0.003 0.005 50 UNM 203 0.0197 0.037 0.035 0.0459 0.011 0.008 0.006 O.OIU 0.006 55 UNM 203 0.0217 0.041 0.039 0.0503 0.012 0.009 0.006 0.004 0.006 60 UNM 169 0.0236 0.1U5 0.1U3 0.0546 0.013 0.010 0.008 0.005 0.008 70 UNM 145
33、0.0276 0.1)51 0.049 0.0610 0.014 0.011 0.008 0.005 0.008 80 UNM 127 0.0315 0.056 0.054 0.0696 0.016 0.012 0.010 0.007 0.010 90 UNM 113 0.0354 0.062 0.058 0.0759 0.0 17 0.013 0.010 0.007 0.010 100 UNM 102 0.0394 0.072 0.068 0.0847 0.019 0.015 0.012 0.008 0.012 110 UNM 102 0.0433 0.082 0.078 0.0957 0.
34、022 O.OIB 0.012 O.OOB 0.012 120 UNM 102 0.0472 0.092 0.088 0.1068 0.025 0.020 0.016 0.012 0.016 140 UNM 85 0.0551 0.103 0.097 0.1197 0.027 0.022 0.016 0.012 0.016 (n) Bold face type indicates preferred sizes (e) Relative to ma. major dia (b) (Av) Derived from mal D, msz H and mean angle MATERIAL: CO
35、RROSION RESISTANT STEELS: ASTM Designation A276 CLASS 303, COND A T R (e) Depth Radius Mm Max 0.002 0.005 0.002 0.005 0.003 0.006 0.003 0.006 O.OIU 0.008 0.004 0.008 0.005 0.010 0.005 0.010 0.006 0.012 0.006 0.012 0.008 0.016 0.008 0.016 0.010 0.020 0.010 0.020 CLASS 416, COND A, HEAT TREAT TO APPRO
36、X 120,000-150,000 PSI (ROCKWELL C2B-34) CLASS 420, COND A, HEAT TREAT TO APPROX 220,000-240,000 PSI (ROCKWELL C50-53) BRASS: TEMPER HALF HARD ASTM Designation B 16 NICKEL SILVER: TEMP ER HARD ASTht. Designation B 151 Alloy C MACHINE Machined surface roughness of heads shall be approximately 63MU in.
37、 arithmetical average FINISH: determined by visual comparison. APPLIED CORROSION RESISTANT STEEL: Passivate COATINGS: BRASS: Bare, Black Oxide or Nickel Flash. NICKEL SILVER: None NOTE: 1. The diameter of the unthreaded body shall bot be more thao the maximum major diameter nor less than the minimum
38、 pitch diameter of the thread. 2. For screw lengths four times tbe major diameter or less, thread length (Lt) shall extend to within two threads of the head beating surface. Screws of gteater length shall have complete threads for a minimum of four major diameters. 3. Screws shall be free of all pro
39、jecting burrs, observed at 3X magnification. 4. All dimensions are in inches. B . Size Desig-nation (a) 40 UNM 45 UNM 50 UNM 55 UNM 60 UNM 70 UNM 80 UNM 90 UNM 100 UNM liD UNM 20 UNM 140 UNM D Thds Basic per Major Inch Dia Ma. 254 0.0157 254 0.0177 203 0.017 203 0.0217 169 0.0236 145 0.0276 127 0.03
40、15 113 0.0354 102 0.0394 102 0.0433 102 0.0472 85 0.0551 SLOTTED HEAD MINIATURE SCREWS A Head Dia M Min 0.041 0.039 0.045 0.043 0.051 0.04 0.056 0.054 0.062 0.058 0.072 0.068 0.082 0.078 0.092 0.088 0.103 0.097 0.113 0.107 0.124 0.116 0.144 0.136 .l. J T -T HrL tf- JTE / UN M THREAO 81.10 ASA “1 ,.J
41、 i“-R rJ +0: TOMINOR 5 OIA MIN Table 4 - Binding Head Binding Head Dimensions H ) T (b) C R Head Hgt Slot Width Slot Depth Cham Radius fer Max Min Max Min Max Min M Max Min 0.010 0.008 0.006 0.004 0.005 0.003 0.002 0.004 0.002 0.011 0.009 0.006 0.004 0.006 0.004 0.002 0.004 0.002 0.012 0.010 0.008 0
42、.005 0.006 0.00. 0.003 0.004 0.002 0.014 0.012 0.008 0.005 0.007 0.005 0.003 0.004 0.002 0.016 0.013 0.010 0.007 0.008 0.006 0.004 0.006 0.003 0.018 0.015 0.010 0.007 0.009 0.007 0.004 0.006 0.0 03 0.020 0.017 0.012 0.008 0.010 0.007 0.005 0.008 0.004 0.022 0.019 0.012 0.008 0.011 0.008 0.005 0.008
43、0.004 0.025 0.021 0.016 I 0.012 0.012 I 0.009 0.006 0.010 0.005 0.028 0.024 0.016 I 0.012 0.014 i 0.011 0.006 0.010 0.005 0.032 0.028 0.020 0.015 0.016 10.012 0.008 0.012 0.006 0.036 I 0.032 0.020 I 0.015 0.018 ! 0.014 O.OOB I 0.012 0.006 (a) Bold face rypeindicates preferred sizes (b) T“ measured f
44、rom bearing surface MATERIAL: CORROSION RESISTANT STEELS: ASTM Designation A276 CLASS 303, COND A CLASS 416, COND A, HEAT TREAT TO APPROX 120,000-150,000 PSI (ROCKWELL 08-34) CLASS 420, COND A, HEAT TREAT TO APPROX 220,000-240,000 PSI (ROCKWELL C5C-53) BRASS: TEMP ER HALF HARD ASTM Designation B 16
45、NICKEL SILVER: TEPER HARD ASTM Designation BISI Alloy C MACHINE Machined surface rcugbness of heads shall be approximately 63MU in. arithmetical average FINISH: determined by isual comparison. APPLIED CORROSION RESISTANT STEEL: Passivate. COATINGS: BRtSS: Bare, Black O:ljde or Nickel Flash. NICKEL S
46、ILVER: None NOTE: 1. The diameter of the unthreaded body shall not be more than the m:l.:rimum mator diameter nor less than rhe minimum pitch diameter of the thread. 2. For screw lengths four times the major diameter Or less, thread length (Lt) shall extend to within twO threads of the head bearing
47、surface. Screws of greater length shall have complete threads for a minimum of four major diameters. 3. Screws shall be free of all projecting burrs, observed at 3X magnification. 4. All dimensions arC“ in inches. 9 L (a) Bold face type indicates preferred sizes (a) Bold face type indicates preferre
48、d sizes AMERICAN STANDARD Table 5 FILLISTER AND PAN HEAD Standard Lengths (a) lOO DEG FLAT HEAD Standard (a) 10 SLOTTED HEAD MINIATURE SCREWS Table 5 (Concluded) BINDING HEAP L Standard Lengths (a) (a) Bold face type indicates preferred sizes 11 AMERICAN STANDARD Appendix A Inch Millimeter Conversio
49、n in. mID in. mm 0.001 0.0254 0.051 1.2954 0.002 0.Q508 0.052 1.3208 0.003 0.0762 0.053 1.3462 0.004 0.10 16 0.054 1.3716 0.005 0.1270 0.055 1.3970 0.006 0.1524 0.056 1.4224 0.007 0.1778 0.057 1.4478 0.008 0.2032 0.058 1.4732 0.009 0.2286 0.059 1.4986 0.010 0.2540 0.060 1.5240 0.011 0.2794 0.061 1.5494 0.012 0.3048 0.062 1.5748 0.013 0.3302 0.063 1.6002 0.014 0.3556 0.064 1.6256 0.015 0.3810 0.065 1.6510 0.016 0.4064 0.066 1.6764 0.017 0.4318 0.067 1.7018 0.018 0.4572 0.068 1.7272 0.019 0.4826 0.069 1. 7526 0.020 0.5080 0.
