AGMA 9006-A16-2016 Flexible Couplings C Basis for Rating.pdf

1、ANSI/AGMA 9006-A16ANSI/AGMA 9006-A16 American National Standard Flexible Couplings Basis for Rating AMERICAN NATIONAL STANDARD ANSI/AGMA 9006-A16 AGMA 2016 All rights reserved i Flexible Couplings Basis for Rating ANSI/AGMA 9006-A16 Approval of an American National Standard requires verification by

2、ANSI that the requirements for due process, consensus and other criteria for approval have been met by the standards developer. Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests.

3、Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made toward their resolution. The use of American National Standards is completely voluntary; their existence do

4、es not in any respect preclude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing or using products, processes or procedures not conforming to the standards. The American National Standards Institute does not develop standards and will in no circumstances

5、 give an interpretation of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. Requests for interpretation of this standard should be addressed to t

6、he American Gear Manufacturers Association. CAUTION NOTICE: AGMA technical publications are subject to constant improvement, revision or withdrawal as dictated by experience. Any person who refers to any AGMA Technical Publication should be sure that the publication is the latest available from the

7、Association on the subject matter. Tables or other self-supporting sections may be referenced. Citations should read: See ANSI/AGMA 9006-A16, Flexible Couplings Basis for Rating, published by the American Gear Manufacturers Association, 1001 N. Fairfax Street, Suite 500, Alexandria, Virginia 22314,

8、http:/www.agma.org. Approved April 18, 2016 ABSTRACT This standard presents criteria and guidelines for the establishment of the basis for ratings of standard flexible couplings. Due to the diversity of coupling types, details of design such as formulas and analysis used to derive the stresses, etc.

9、 are often considered proprietary and are not considered in this standard. This standard is of importance to coupling manufacturers, users and equipment designers for the proper selection, comparison and application of flexible couplings. Published by American Gear Manufacturers Association 1001 N.

10、Fairfax Street, Suite 500, Alexandria, Virginia 22314 Copyright 2016 by American Gear Manufacturers Association All rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher. Printed i

11、n the United States of America ISBN: 978-1-55589-057-5 American National Standard AMERICAN NATIONAL STANDARD ANSI/AGMA 9006-A16 AGMA 2016 All rights reserved ii Contents Foreword . iii 1 Scope 1 1.1 Applicability . 1 1.2 Exclusions . 1 2 Normative references . 1 3 Symbols and definitions 1 4 Torque

12、rating 2 4.1 Nominal torque rating 2 4.2 Peak torque rating . 3 4.3 Application specific torque limits . 3 4.3.1 Momentary torque limit 3 4.3.2 Vibratory torque rating . 3 5 Speed ratings 3 5.1 Rated speed 3 5.2 Additional speed considerations . 3 5.2.1 Bursting speed. 3 5.2.2 Lateral critical speed

13、 . 3 5.2.3 AGMA balance class rated speed . 3 6 Misalignment ratings . 4 7 Temperature ratings . 4 8 Life expectancy of flexible couplings 4 8.1 Sliding or rolling element couplings. 4 8.2 Elastomeric element couplings . 4 9 Service factors 5 10 Factor of safety, FS . 5 11 Coupling stress analysis a

14、nd theories of failure . 5 11.1 Ductile failure theory . 5 11.2 Brittle failure theory . 7 Annexes Annex A (informative) Relationship of Angular and Parallel Misalignment . 9 Annex B Bibliography 13 Figures Figure 1 Stress convention 6 Figure 2 Graphical representation of the Coulomb-Mohr Theory 7 F

15、igure A.1 Angular misalignment between two shafts . 9 Figure A.2 Parallel misalignment between two shafts . 9 Figure A.3 Combined angular and parallel misalignment between two shafts 10 Figure A.4 Schematic of double flexing element coupling accommodating angular misalignment between two shafts . 11

16、 Figure A.5 Schematic of double flexing element coupling accommodating parallel misalignment between two shafts . 11 Figure A.6 Schematic of double flexing element coupling accommodating combined parallel and angular misalignment between two shafts 12 Tables Table 1 Symbols, terms and definitions .

17、2 AMERICAN NATIONAL STANDARD ANSI/AGMA 9006-A16 AGMA 2016 All rights reserved iii Foreword The foreword, footnotes and annexes, if any, in this document are provided for informational purposes only and are not to be construed as a part of ANSI/AGMA 9006-A16, Flexible Couplings Basis for Rating. The

18、intent of ANSI/AGMA 9006-A16 is to provide insight into variables that are considered by coupling designers when rating flexible couplings. This standard was developed after intensive study of existing literature, design practices, and manufacturing procedures for the rating of flexible couplings Th

19、e first draft of ANSI/AGMA 9006-A16 was created in June 2005. It was approved by the AGMA membership in January 2016. It was approved as an American National Standard on April 18, 2016. Suggestions for improvement of this standard will be welcome. They should be sent to techagma.org. AMERICAN NATION

20、AL STANDARD ANSI/AGMA 9006-A16 AGMA 2016 All rights reserved iv PERSONNEL of the AGMA Flexible Couplings Committee Chairman: Glenn Pokrandt. Rexnord Industries, LLC (Retired) Vice Chairman: Todd Schatzka . Rexnord Industries, LLC ACTIVE MEMBERS T. Glasener. Regal Power Transmission Solutions B. Gree

21、nlees A-C Equipment Services C. Hatseras KTR Corporation D. Hindman Rexnord Industries, LLC D. Konopka. Ameridrives Couplings P. Petruska . Lovejoy, Inc. L. Riggs Regal Power Transmission Solutions J. Rubel Baldor Electric Company AGMA 2016 All rights reserved 1 AMERICAN NATIONAL STANDARD ANSI/AGMA

22、9006-A16 American National Standard Flexible Couplings Basis for Rating 1 Scope This standard presents criteria and guidelines for the basis of flexible coupling ratings. It is not a comprehensive rating method that can be applied to a specific product or manufacturer. Due to the diversity of coupli

23、ng types, this standard presents generally accepted practices rather than rigorous engineering analyses. This standard is of importance to coupling manufacturers, users and equipment designers for the proper selection and application of flexible couplings. 1.1 Applicability This document is applicab

24、le to standard couplings as defined by ANSI/AGMA 9009. 1.2 Exclusions Details of design, such as formulas and analyses used to derive the specific coupling stresses, are often considered proprietary and are not considered in this standard. It does not address special couplings that are engineered an

25、d manufactured specifically to meet the operating conditions of the equipment train in which they will be installed. Additionally, flexible shafts, quill shafts, universal joints, magnetic couplings, or devices which exhibit slip such as clutches, fluid couplings, or torque converters are also exclu

26、ded. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this American National Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements base

27、d on the American National Standard are encouraged to investigate the possibility of applying the most recent editions of the standards listed. ANSI/AGMA 9000, Flexible Couplings Potential Unbalance Classification ANSI/AGMA 9004, Flexible Couplings Mass Elastic Properties and Other Characteristics A

28、NSI/AGMA 9009, Flexible Couplings Nomenclature for Flexible Couplings ANSI/AGMA 9104, Flexible Couplings Mass Elastic Properties and Other Characteristics (Metric Edition) ANSI/AGMA 9110, Flexible Couplings Potential Unbalance Classification (Metric Edition) 3 Symbols and definitions The terms used

29、in this document are defined in Table 1. NOTE: These definitions may differ from those in other AGMA publications. The user should not assume that familiar terms can be used without a careful study of their definitions. AMERICAN NATIONAL STANDARD ANSI/AGMA 9006-A16 AGMA 2016 All rights reserved 2 Ta

30、ble 1 Symbols, terms and definitions Symbol Definition Where first used FS Factor of safety Clause 11 Kf Stress concentration factor Eq. 2 Kfs Shear stress concentration factor Eq. 3 Se Full reversal endurance limit in bending Eq. 2 Sse Full reversal endurance limit in shear Eq. 3 Ssy Shear yield st

31、rength Eq. 3 SUT Ultimate tensile strength of the material Eq. 5 SUC Ultimate compressive strength of the material Eq. 5 Sy Tensile yield strength Eq. 2 Mohrs circle normal stress axis Fig. 2 1 Maximum principle stress Eq. 5 3 Minimum principle stress Eq. 5 av Mean component of stresses x, y, z Eq.

32、2 e Stress in simple tension that is equivalent to the three dimensional loading Eq. 1 equiv Equivalent static stress by the Soderberg method Eq. 2 vib Vibratory component of stresses x, y, z Eq. 2 x Stress in the x direction Eq. 1 y Stress in the y direction Eq. 1 z Stress in the z direction Eq. 1

33、Mohrs circle shear stress axis Fig. 2 s av Mean component of shear stresses xy, yz and zx Eq. 3 s equiv Equivalent static shear stress by the Soderberg method Eq. 3 s vib Vibratory component of shear stresses xy, yz and zx Eq. 3 xy Shear stress on the plane perpendicular to the x axis and in the y d

34、irection Eq. 1 yz Shear stress on the plane perpendicular to the y axis and in the z direction Eq. 1 zx Shear stress on the plane perpendicular to the z axis and in the x direction Eq. 1 4 Torque rating 4.1 Nominal torque rating The nominal torque rating is established by the manufacturer for a stat

35、ed combination of speed, misalignment, axial displacement and temperature. Nominal torque rating may also be referred to as normal torque or continuous torque rating. This rating is based on a uniform operating condition with no additional service factors applied. See Clause 9 for a definition of se

36、rvice factor. AMERICAN NATIONAL STANDARD ANSI/AGMA 9006-A16 AGMA 2016 All rights reserved 3 4.2 Peak torque rating The peak torque rating is the coupling manufacturers rating that accounts for occasional, higher than normal torques that exceed the nominal torque rating. Peak torque rating is based o

37、n: - material strength; - number of cycles as established by the manufacturer; - maximum continuous misalignment; - rated speed. NOTE: For certain types of couplings, particularly those with elastomeric elements or inserts, the coupling peak torque ratings may also be a function of the operating tem

38、perature. 4.3 Application specific torque limits 4.3.1 Momentary torque limit The momentary torque limit corresponds to a factor of safety of 1.0 with respect to the most highly stressed component utilizing a combination of speed, misalignment, and axial displacement. The coupling can experience dam

39、age at this limit. For metallic components the limit may depend on the yield strength. For elastomeric components the limit can be dependent on environmental conditions such as temperature and humidity. 4.3.2 Vibratory torque rating The vibratory torque rating is the coupling rating in applications

40、with vibratory torque present. The rating considers the ambient temperature and provides a torque value not to be exceeded for vibratory frequencies below 10Hz. For elastomeric couplings operating at frequencies greater than 10 Hz, further review of ambient temperature and the coupling damping power

41、 must be considered since the heat produced from damping may exceed the coupling capability. 5 Speed ratings 5.1 Rated speed The rated speed is the maximum rotational speed (rpm) at which the coupling is capable of transmitting the nominal rated torque while simultaneously subjected to the maximum c

42、ontinuous misalignment. 5.2 Additional speed considerations Speed ratings may be influenced by bursting speed, mounting type/bore to shaft fit, lateral critical speed, balance class, thermal considerations or other factors. 5.2.1 Bursting speed The bursting speed is the rotational speed at which the

43、 centrifugal stress of the coupling exceeds the yield strength of the material. 5.2.2 Lateral critical speed The lateral critical speed is that speed which matches the lateral natural frequency of the rotating component(s). See ANSI/AGMA 9004 and ANSI/AGMA 9104 for further discussion, calculations a

44、nd analysis methods. 5.2.3 AGMA balance class rated speed The AGMA balance class rated speed is the allowable operating speed determined by the AGMA balance class defined in ANSI/AGMA 9000 and ANSI/AGMA 9110. AMERICAN NATIONAL STANDARD ANSI/AGMA 9006-A16 AGMA 2016 All rights reserved 4 6 Misalignmen

45、t ratings The misalignment ratings consider a combination of axial displacement, parallel offset and angular misalignment that the coupling is designed to accommodate. For definitions, see ANSI/AGMA 9009. Refer to Annex A for a discussion about the interaction between parallel offset and angular mis

46、alignment in flexible couplings. 7 Temperature ratings Temperature ratings of a coupling are based on material characteristics of its components. Limiting factors may include seals, lubricants, composites, coatings, and elastomers. The continuous operating temperature is the temperature range where

47、performance can be predicted based on temperature factors used to either de-rate the nominal coupling torque or provide service factor to a component operating close to the material limit. In couplings designed to damp vibration, temperature can limit the amount of damping or the ability for the cou

48、pling to dissipate the heat generated when damping vibration. 8 Life expectancy of flexible couplings Life expectancy of a coupling is based on a number of variables including material properties, operating conditions (i.e., loads, misalignments, starts/stops, duty cycles and critical frequencies),

49、maintenance practices and environmental factors (i.e., temperature, humidity, ultraviolet light exposure, air quality and chemical exposure). 8.1 Sliding or rolling element couplings Gear, grid and chain couplings are examples with sliding or rolling elements. While correct lubrication and regular inspection/preventative maintenance will greatly extend life expectancy, sliding or rolling components do wear down over time, giving this coupling group a finite life. Specific coupling li