1、AMERICAN NATIONAL STANDARD General Purpose Tapered and Reduced Cross Section Retaining Rings ANSI B27.7 - 1977 METRIC REAFFIRMED 1999 FOR CURRENT COMMITTEE PERSONNEL PLEASE SEE ASME MANUAL AS-11 SECRETARIAT SOCIETY OF AUTOMOTIVE ENGINEERS THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS . PUBLISHED BY T
2、HE AMERICAN SOCIETY OF MECHANICAL ENGINEERS United Engineering Center 345 East 47th Street New York, N. Y. 1001 7 No part of this document may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. Copyright 0 1977 by THE AME
3、RICAN SOCIETY OF MECHANICAL ENGINEERS All Rights Resewed Printed in USA. FOREWORD American National Standards Committee B27 for the standardization of plain and lock washers was organized in March 1926, as Sectional Committee B27 under the aegis of the American Standards Associa- tion (later the Uni
4、ted States of America Standards Institute and, as of October 6, 1969, the American National Standards Institute Inc.), with the Society of Automotive Engineers and The American Society of Mechanical Engineers as joint secretariats. In 1950, this Committee has been designated responsibility for stand
5、ardization of washers and machine rings. At a meeting of ANSI B27 Standards Committee held on February 4,1971 it was recommended to the secretariats (ASME and SAE) that subcommittee 1, 2 and 4 on washers be merged into ANSI B18 Stan- dards Committee and that Subcommittee 3 on retaining rings become
6、a separate Standards Committee re- taining the B27 designation. This change was subsequently approved by ANSI. Formation of Subcommittee 1 on tapered and reduced section retaining rings was authorized by Stan- dards Committee B27 at its meeting on October 15, 1974. At this meeting, it was decided th
7、at no further effort should be expended on inch dimensional products and Subcommittee 1 was assigned the respon- sibility of preparing American metric standards for tapered and reduced section retaining rings. Subcommittee 1 prepared a draft proposal, General Purpose Tapered and Reduced Cross Sectio
8、n Retain- ing Rings which was balloted on June 16, 1975. At a subcommittee meeting held on February 17, 1976 results from the letter ballot was reviewed. The proposal was accepted by the subcommittee and presented to the B27 Standards Committee at its May 7, 1976 meeting. At that mee.ting a letter b
9、allot of the entire committee was authorized. The Standard was duly approved by the committee and its sponsors and sub- mitted to the American National Standards Institute for designation as an American standard. This was granted on October 20, 1977. iii AMERICAN NATIONAL STANDARDS COMMITTEE B27 Sta
10、ndardization of Retaining Rings, Retaining Clips and Similar Devices (The following is the roster of the Committee at the time of approval of this standard) OFFICERS J. B. Levy, Chairman R. L. Berkbigler, Vice-Chairman Kurt Wessely, Secretary COMMITTEE PERSONNEL AMERICAN SOCIETY OF MECHANICAL ENGINE
11、ERS, THE J. B. Levy, General Electric Company, Schenectady, New York E. R. Friesfh, alternate, Deere Internal Type-3BM1; E-Ring Type-3CMI) 1. INTRODUCTORY NOTES 1.1 Scope This standard is intended to cover complete general and dimensional data for three series of general pur- pose tapered and reduce
12、d cross section retaining rings which may be used with the nominal size shafts and housings listed and in grooves of the recommended dimensions listed. Also included are formulas and tol- erances on which dimensional data are based. Three appendixes include guidance for assembly and recom- mended st
13、andard drawing formats. The inclusion of dimensional data in this standard is not intended to imply that all of the products de- scribed are stock production sizes. Consumers should consult with manufacturers concerning lists of stock production sizes. 1.2 Ring Types 1.2.1 External Rings. Dimensions
14、 of .basic external retaining rings, and grooves for various shaft sizes are given in Table 4. 1.2.2 Internal Rings. Dimensions for basic internal retaining rings, and grooves for various housing sizes are given in Table 5. 1.2.3 External E-Rings. Dimensions of E-Type ex- ternal retaining rings, and
15、 grooves for various shaft sizes are given in Table 6. 1.2.4 Designations. It is recommended that the pre- ferred type designations be used to identify these rings on drawings, parts list, and other engineering documentation. The basic external rings in this stan- dard are Type 3AM1. The basic inter
16、nal rings in this standard are Type 3BM1. The E-Type external rings in this standard are Type 3CM 1. 1.3 Applicability The rings denoted in this standard are intended primarily for use with the shaft, housing, and groove sizes recommended; however, in certain cases these diameters may be altered som
17、ewhat to suit the re- quirements of a particular design. When such changes are made, care should be taken to not alter the shaft or housing size to such an extent that the ring will take enough permanent set to allow a loose fit after the ring has been assembled into the groove. Neither should the g
18、roove diameter be altered to the extent to permit the ring to fit loosely. 1.4 Dimensions All dimensions in this standard are in millimetres unless otherwise stated. 1.5 Supplementary Information Allowable loads, maximum radii and chamfers, clearance dimensions, gaging diameters and rpm limits for a
19、ll 3 ring series are included in Appendix A, B and C. 2. GENERAL DATA 2.1 Basic Retaining Rings Type 3AM1 retaining rings covered by this standard are spread over a shaft by means of a pliers or special tool and allowed to relax and seat in a circumferential groove, thereby providing an external pro
20、truding shoulder which can be used for locating and retaining a part on the shaft. Type 3BM1 retaining rings covered by this standard are compressed into a housing by means of a pliers or special tool and allowed to relax and seat in a circum- ferential groove, thereby providing an internal pro- tru
21、ding shoulder which can be used for locating and retaining a part contained inside of the housing. In both cases, the rings have a tapered section to provide a more uniform distribution of stresses during expansion or compression. AMERICAN NATIONAL STANDARD TAPERED AND REDUCED CROSS SECTION RETAININ
22、G RINGS ANSI 027.7-1977 2.2 E-Type Retaining Rings Type 3CM 1 retaining rings covered by this standard contain 3 prongs connected by a reduced section bridge to provide greater resilience during installation. The rings are installed radially, usually by means of an applicator, and provide a high sho
23、ulder for abut- ment by a retained part. 3. MATERIAL Standard materials used in the manufacture of the retaining rings shall be carbon spring steel, corrosion resistant steel, or beryllium copper. 3.1 Carbon Spring Steel Retaining rings made from carbon spring steel shall conform to the chemical com
24、position of SAE 1060 to 1090 or AISI 1060 to 1090 or equivalent and have the following physical properties: 3.1.1 Heat Treatment. The retaining rings should be heat treated by austempering to the Rockwell C hard- ness values as specified in Table 1. Table 1 Hardness Ranges for Tapered and Reduced Cr
25、oss Section Retaining Rings 3AM 1 3BM1 Ring Size Rockwell C 48-52 27 through 250 47-51 88 through 100 49-53 21 through 26 48-52 27 through 85 50-54 14 through 20 49-53 13 through 26 51-55 8 through 13 51-55 7 through 12 Rockwell C Ring Size 3CM 1 Ring Size Rockwell C 2 through 8 48-52 9 through 25 4
26、9-53 3.1.2 Surface Treatment. All retaining rings shall be available with the following protective finishes: 3.7.2.7 Phosphate Coating. Finish shall consist of basic phosphate treatment, and subsequent protective coating of any protective compound other than paint type. Parts furnished to this speci
27、fication shall show no rust on significant surfaces when exposed to a salt spray resistance test for a period of 2 hours, mini- mum. 3.1.2.2 Cadmium or Zinc Plating. Basic require- ments for plated finishes of either cadmium or zinc shall be a plated finish of 0.005 mm minimum thick- 2 ness, treated
28、 to withstand 32 hours neutral salt spray test without evidence of white corrosion products. Basis metal corrosion should not exceed one spot per 645 square millimetres of significant surface, and such spots should be visible to the naked eye and should not exceed 1.5 millimetres in any dimension. .
29、 3.7.2.3 Black Oxide. Finish shall be essentially a black iron oxide of the magnetite type produced by conversion of the metal surface during immersion of the part in a hot alkaline salt solution or in a mixed salt fusion bath. The degree of pitting or metal loss shall be as specified by the purchas
30、er, but in no case shall this be an amount detrimental to the perfor- mance of the part. The finish shall be black in color and lusterous in appearance. 3.7.2.4 Where plated or coated rings are subject to hydrogen embrittlement they shall be baked for three hours at 375“ F (190C), or other suitable
31、times and temperatures, as soon as possible after the plating or coating operation to obviate such embrittlement. 3.2 Corrosion Resistant Steel Retaining rings made from corrosion resistant steel shall conform to the chemical composition of PH 15-7Mo or equivalent (AISI 632-AMS 5520) and have the fo
32、llowing physical properties: 3.2.1 Heat Treatment. The retaining rings should be heat treated to the Rockwell C hardness values within the range of 44-5 1. 3.2.2 Surface Treatment. Retaining rings shall be cleaned free of scale, grease, oil and other foreign ma- terial. Surfaces shall- be finished c
33、ompletely before passivation and no operations shall be performed after passivating which will disturb the passivated surface fii. The entire surface of the retaining rings shall be effectively passivated. 3.3 Beryllium Copper Retaining rings made from beryllium copper shall conform to the chemical
34、composition of Alloy 25, CDA 172 or equivalent (UNSC 17200) and have the following physical properties: 3.3.7 Heat Treatment. The retaining rings should be heat treated to the Rockwell C hardness values with- in the range of 37-43. 3.3.2 Surface Treatment. Retaining rings shall be cleaned to remove
35、oxide formed as a result of the heat treating process. Since these rings have extremely AMERICAN NATIONAL STANDARD TAPERED AND REDUCED CROSS SECTION RETAINING RINGS ANSI 827.7-1977 high resistance to most types of atmospheric corro- sion, further protective finishes are usually not re- quired. 4. HA
36、RDNESS TESTING PROCEDURE The surfaces of both sides of each sample retaining ring shall be prepared for hardness testing by removal of all plating and other surface conditions which may affect the hardness reading. The load shall be applied perpendicular to the surface being tested within 7 degrees.
37、 Rockwell C Scale shall be used on prepared samples having a thickness of 1.3 mm or greater. Rockwell A Scale, or Rockwell superficial 45N, 30N, or 15N Scales shall be used on samples having lesser thickness and readings coverted to Rockwell C. Pre- pared samples shall be sufficiently wide to preven
38、t bulging of the sides by the penetrator. 5. PERMANENT SET LIMITS The following procedures should be used for deter- mining if the permanent set of the ring is within the allowable limits: 5.1 Basic External (3AM1) Retaining Rings 1. Expand the ring with a plier until it just fits over a shaft 1% la
39、rger than the nominal shaft diameter. Repeat this procedure 4 more times with the same ring. The ring shall not crack during this procedure. 2. Measure the ring diameter )in the three places shown in Figure 1. FIGURE 1 PERMANENT SET MEASUREMENTS FOR TYPE 3AM1 RINGS 3. Compute the average of the 3 di
40、ameters and compare it to the minimum groove diameter listed in the Data Chart for that ring. In all cases the average diameter after permanent set should be less than the groove diameter to insure that the ring will seat tightly. 5.2 Basic Internal (3BM1) Retaining Rings 1. Compress the ring with a
41、 plier until the lugs abut each other. Repeat this procedure 4 more times during this procedure. 2. Measure the ring diameter (D) in the three places shown in Figure 2. FIGURE 2 PERMANENT SET MEASUREMENTS FOR TYPE 3BM1 RINGS 3. Compute the average of the 3 diameters and compare it to the maximum gro
42、ove diameter listed in the Data Chart for the ring. in all cases the average diameter after permanent set should be greater than the groove diameter to insure that the ring will seat tightly. 5.3 E-Type (3CM1) External Retaining Rings The rings shall, upon being installed in the minimum groove diame
43、ter by an applicator or similar tool, grip the minimum groove diameter and shall have no less than 3 point contact. 6. IRREGULARITY LIMITATIONS 6.1 Dish Dish limitations of tapered and reduced section re- taining rings as shown in Figure 3 shall not exceed the dimensions specified in Table 2 for the
44、 applicable ring series thickness. Table 2 Dish Limitations for Tapered and Reduced Section Retaining Rings Types 3AM106 t0.06 t0.06 t0.06 t0.06 t0.06 20.06 t0.06 i0.06 t0.06 t0.06 t0.06 t0.06 t0.06 t0.06 t0.06 10.06 tO.06 t0.06 t0.06 t0.06 t0.06 t0.06 t0.06 t0.06 r0.08 tO.08 tO.08 0.08 t0.08 tO.08
45、t 0.08 tO.08 tO.08 t0.08 i0.08 tO.08 kO.08 t0.08 tO.08 tO.08 tO.08 50.08 0.08 tO.08 tO.08 tO.08 t0.08 tO.08 tO.08 tO.08 t0.08 t0.06 0.65 0.65 0.75 0.90 ,1 .oo 1.15 1.30 1.40 1.50 1.70 1.60 1 .80 2.05 2.10 2.25 2.35 2.40 2.50 2.70 2.80 2.9 3.0 2.9 3.1 3.2 3.3 3.6 3.8 3.9 4.1 4.3 4.4 4.6 4.7 4.8 4.9 5
46、.0 5.1 5.3 5.4 5.4 5.6 5.6 5.7 5.8 6.0 6.2 6.3 6.4 6.6 6.6 7 .O 7.1 7.3 7.5 7.5 7.9 8.0 4.75 3.80 6.60 5.70 8.45 7.50 10.35 9.40 11.35 12.30 13.25 14.15 15.10 16.10 17.00 18.85 17.95 19.80 20.70 21.65 22.60 23.50 24.50 25.45 26.40 30.20 28.35 32.00 32.90 33.85 35.8 37.7 39.6 40.5 42.4 43.3 45.2 47.2
47、 49.1 51 .O 51 .8 53.8 54.7 56.7 58.6 61.6 64.5 66.4 68.3 71.2 74.0 75.9 77.8 80.6 83.5 85.4 90.2 95.0 -0.08 -0.08 -0.08 -0.10 -0.10 -0.10 -0.10 -0.1 2 -0.1 2 -0.12 -0.12 -0.12 -0.1 5 -0.15 -0.15 -0.15 -0.1 5 -0.15 -0.1 5 -0.15 -0.1 5 -0.15 -0.1 5 -0.20 -0.20 -0.20 4.20 -0.20 -0.20 -0.20 -0.30 -0.30
48、 -0.30 -0.30 -0.30 -0.30 -0.30 -0.30 -0.30 -0.30 -0.30 -0.80 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 -0.40 - +O.W to.10 +0.10 to.15 +0.15 +0.15 M.15 +0.15 to.15 to.15 to.15 +0.15 +0.15 to.15 +0.15 +0.15 to.15 to.15 +0.15 +0.15 +0.15 +0.15 to.15 to.15
49、 to.15 W.15 +0.15 to.15 +0.15 to.15 +0.15 to.20 +0.20 to.20 t0.20 to.20 t0.20 +0.20 to.20 to.20 to20 +0.20 t0.20 t0.20 tO.20 tO.20 to.20 to.20 t0.20 t0.20 to.20 t0.20 t0.20 t0.20 t0.M to20 t0.20 to.m 0.3 0.4 0.5 0.6 0.8 0.8 0.9 1 .o 1 .o 1 .o 1.2 1.3 1.4 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.3 2.3 2.3 2.4 2.5 2.7 3.0 3.1 3.2 3.3 3.4 3.6 3.8 3.9 4.0 4.2 4.3 4.2 4.5 4.8 4.8 4.9 4.9 5.1 5.1 5.3 5.4 5.5 6.0 5.7 6.1 6.3 6.6 6.7 6.9 7.2 7.5 +0.25 -0.40 +0.35 -0.50 +0.35 -0.50 t0.35 -0.50 t0.35 -0.50 C0.35 6.50 +0.35 -0.50 t0.35 -0.50 t0.35 -0.65 C0.35 -0.65 t0.35 -0.65 t0.35 -0.65 t0.35 -0.65 t0.35
