1、The International Authority on Air System ComponentsAIR MOVEMENT AND CONTROLASSOCIATION INTERNATIONAL, INC.ANSI/AMCAStandard 204-05Balance Quality andVibration Levels for FansAn American National StandardApproved by ANSI on March 28, 2012(R2012)ANSI/AMCA Standard 204-05(R2012)Balance Quality and Vib
2、ration Levels for FansAir Movement and Control Association International30 W. University DriveArlington Heights, Illinois60004This edition of ANSI/AMCA Standard 204 was adopted by the membership of the Air Movement and Control Association International, Inc., on 03 August 2003. It was reaffirmed by
3、the Air Movement Division and approved as an American National Standard on March 28, 2012.This standard addresses the need of both the users and manufacturers of fans for technically accurate but uncomplicated information of the subjects of fan balance precision and vibration levels. The data presen
4、ted herein is referenced to applicable national and international standards and is in harmony with these stan-dards, including ISO 14694:2003, Industrial fans - Specification for balance quality and vibration levels. Information from the reference standards is supplemented by years of experience on
5、the part of committee members and from other contributors in the industry. 2012 by Air Movement and Control Association International, Inc.All rights reserved. Reproduction or translation of any part of this work beyond that permitted by Sections 107 and 108 of the United States Copyright Act withou
6、t the permission of the copyright owner is unlawful. Requests for permission or further information should be addressed to the Executive Director, Air Movement and Control Association International, Inc. at 30 West University Drive, Arlington Heights, IL 60004-1893 U.S.A.Air Movement and Control Ass
7、ociation International, Inc. will consider and decide all written complaints regarding its standards, certification programs, or interpretations thereof. For information on procedures for submitting and handling complaints, write to:Air Movement and Control Association International30 West Universit
8、y DriveArlington Heights, IL 60004-1893 U.S.A.AMCA International, Incorporatedc/o Federation of Environmental Trade Associations2 Waltham Court, Milley Lane, Hare HatchReading, Berkshire, United KingdomRG10 9THAMCA uses its best efforts to produce standards for the benefit of the industry and the pu
9、blic in light of avail-able information and accepted industry practices. However, AMCA does not guarantee, certify or assure the safety or performance of any products, components or systems tested, designed, installed or operated in accordance with AMCA standards or that any tests conducted under it
10、s standards will be non-hazardous or free from risk.AMCA PublicationsAuthorityCopyrightObjectionsDisclaimerDr. John Cermak Acme Engineering indus-trial process applications; mine/tunnel ventilation applica-tions, and power generation applications. Other applications are not specifically excluded, ex
11、cept as follows:Excluded are installations that involve severe forces, impacts, or extreme temperature acting on the fan.Fan foundations and installation practices are beyond the scope of this standard. Foundation design and fan installa-tion are not normally the responsibilities of the fan manufac-
12、turer. It is fully expected that the foundation upon which the fan is mounted will provide the support and stability neces-sary to meet the vibration criteria of the fan as it is delivered from the factory.Other factors such as impeller cleanliness, aerodynamic conditions, background vibration, oper
13、ation at rotational speeds other than those agreed upon, and maintenance of the fan affect fan vibration level but are beyond the scope of this standard.This standard is intended to cover only the balance or vibra-tion of the fan and does not take into account the effect of fan vibration on personne
14、l, equipment, or processes.Any or all portions of this standard, or modifications thereof, are subject to agreement between the concerned parties.2. Normative ReferencesThe following standards contain provisions that, through specific reference in this text, constitute provisions of this American Na
15、tional Standard. At the time of publication of this standard the editions indicated were valid. All standards are subject to revision, and parties to agree-ments based on this American National Standard are encouraged to investigate the possibility of applying the most recent editions of the standar
16、ds listed below.1 ANSI S2.7-1982 (R1997) Balancing TerminologyAmerican National Standards Institute11 West 42nd Street, New York, NY 10035 U.S.A 2 ISO 1925:2001 Mechanical Vibration Balancing VocabularyInternational Organization for Standardization1 Rue de Varembe, Case Oistake 56, Ch-1211, Geneve 2
17、0, SWITZERLAND3 ANSI S2.19-1989 (R1997) Balance Quality of Rigid Rotating Bodies (ISO 1940) American National Standards Institute, 11 West 42ndStreet, New York, NY 10035 U.S.A.3. Definitions / Units of Measure / Symbols3.1 Definitions 3.1.1 BalancingThe process of adding or removing mass in a plane
18、or planes on a rotor in order to move the center of gravity towards the axis of rotation.3.1.2 Balance quality gradeThe recommended limits for residual unbalance of a rotor based upon the intended application. (Note: Commonly used balance quality grades in ANSI S2.19 refer to the vibra-tion that wou
19、ld result if the rotor operated in free space, i.e., Balance Quality Grade G6.3 corresponds to a shaft vibra-tion of 6.3 mm/s velocity, at the operating rotational speed of the rotor). The value represents the product of the unbal-ance multiplied by the angular velocity and divided by the weight of
20、the rotor.3.1.3 DisplacementThe distance that a body moves from a stationary or neutral position.2 | ANSI/AMCA 204-05 (R2012)3.1.4 Electrical run-outThe total measured variation in the apparent location of a ferrous shaft surface during a complete slow rotation of that shaft as determined by an eddy
21、 current probe system. This measurement may be affected by variations in the electrical/magnetic properties of the shaft material as well as varia-tions in the shaft surface.3.1.5 Fan application categoryA grouping used to describe fan applications, their appropri-ate Balance Quality Grades, and Rec
22、ommended Vibration Levels.3.1.6 Fan assemblyThe fan assembly consists of those items typically packaged together as “a complete fan”, including, as applicable: rotor, bearings, belts, housing, motor, sheaves, and mounting base/structure. In the case of a cooling tower application, the fan assembly i
23、s considered to consist of the rotor alone.3.1.7 Fan rotorAn assembly consisting of a fan impeller mounted on its shaft. (AMCA 99-0066) 3.1.8 Fan vibration levelThe vibration amplitude measured at a fan bearing and expressed in units of displacement or velocity.3.1.9 FilterA device used to separate
24、vibration on the basis of its frequency. Vibration meters normally have adjustable filters to allow measurements at a frequency range of interest.3.1.10 Filter-in; sharpVibration measured only at a frequency of interest. 3.1.11 Filter-out; broad passVibration measured over a wide frequency range; so
25、me-times called “overall” vibration. 3.1.12 Flexible supportA fan support system designed so that the first natural frequency of the support is well below the frequency corre-sponding to the operating rotational speed of the fan. Often this involves compliant elastic elements between the fan and the
26、 support structure. “This condition is achieved by suspending the machine on a spring or by mounting on an elastic support (springs, rubber, etc.). The natural oscilla-tion frequencies of the suspension and machine is typically less than 25% of the frequency corresponding to the lowest speed of the
27、machine under test”-NEMA MG 1-1993, Rev. 1, Part 7, Section 7.06.1.3.1.13 FoundationRefers to the component to which the fan is mounted that provides the necessary support. A fan foundation must have sufficient mass and rigidity to avoid vibration amplification.3.1.14 FrequencyIn cyclical motion, th
28、e number of cycles that occur per second (Hz) or cycles occurring per minute (CPM).3.1.15 Mechanical run-outThe total actual variation in the location of a shaft surface during a complete slow rotation of the shaft as determined by a stationary measurement device such as a dial indicator.3.1.16 Jour
29、nalThe part of a rotor which is in contact with or supported by a bearing in which it revolves. ISO 19253.1.17 MilsA unit of measure that describes displacement. One mil equals one-thousandth of an inch (1 mil = 0.001 inch)3.1.18 Overall fan vibrationSee Filter-out; broad pass.3.1.19 Peak (pk)A disp
30、lacement, velocity, or acceleration value occurring at the maximum deviation from a zero or stationary value. See Figure 3.1 and see also: RMS.3.1.20 Peak-to-peak (pk-pk)The total range traversed in one cycle. Peak-to-peak read-ings apply to displacement only.3.1.21 Residual unbalanceUnbalance of an
31、y kind that remains after balancing. ANSI S2.7-1982 (R1986)3.1.22 Rigid supportA fan support system designed so that the first natural frequency of the system is well above the frequency corre-sponding to the operating rotational speed of the fan. “Note: The rigidity of a foundation is a relative qu
32、antity. It must be considered in conjunction with the rigidity of the machine bearing system. The ratio of bearing housing vibration to foundation vibration is a characteristic quantity for the evaluation of foundation flexibility influences. A foundation may be considered massive if the vibration a
33、mplitude of the foundation (in any direction) near the machines feet or base frame are less than 25% of the maximum amplitude that is measured at the adjacent bearing housing in any direction.” -NEMA MG1-1993, Rev. 1, Part 7, Section 7.06.2. 3.1.23 Rigid rotorA rotor is considered to be rigid when i
34、ts unbalance can be corrected in any two arbitrarily selected planes (of rota-tion). After the correction, its residual unbalance does not change significantly relative to the shaft axis at any (rota-ANSI/AMCA 204-05 (R2012) | 3tional) speed up to the maximum service (rotational) speed. Adapted from
35、 ANSI S2.7-1982(R1986)3.1.24 RMSThe root-mean-square value. For true sinusoidal motion the RMS value is equal to 2/2 times the peak value.3.1.25 RotorA body, capable of rotation, generally with journals which are supported by bearings. ANSI S2.7 See also: Fan Rotor.3.1.26 Speed, balancingThat rotati
36、onal speed, expressed in revolutions per minute (rpm), at which a (fan) rotor is balanced. ANSI S2.73.1.27 Speed, designThe maximum rotational speed, measured in revolutions per minute (rpm), for which the fan is designed to operate.3.1.28 Speed, serviceRotational speed, measured in revolutions per
37、minute (rpm), at which a rotor operates in its final installation or environment.3.1.29 Tri-axial setA set of three measurements taken in three mutually perpen-dicular directions, normally: horizontal, vertical, and axial.3.1.30 Trim balanceThe balance process that makes minor unbalance correc-tions
38、 which may become necessary as a result of the fan assembly or installation process.3.1.31 UnbalanceA condition of a rotor in which its rotation results in centrifu-gal forces being applied to the rotors supporting bearings. Unbalance is usually measured by the product of the mass of the rotor times
39、 the distance between its center of gravity and its center of rotation in a plane.3.1.32 VelocityIn cyclic motion, the time rate of change in displacement.3.1.33 VibrationThe alternating mechanical motion of an elastic system, the components of which are amplitude, frequency and phase. In general pr
40、actice, vibration values are reported as: displacement, peak-to-peak, in mm (mils) velocity, peak, in mm/s (in./s) acceleration, peak, in gs, or m/s2(in./s2)Standard gravitational acceleration (1g) = 9.80665 m/s2(386.09 in./s2)3.1.34 Vibration spectrumA graphical representation of vibration amplitud
41、e versus frequency.3.1.35 Vibration transducerA device designed to be attached to a mechanical system for measurement of vibration. It produces an electronic signal that can be displayed or otherwise processed, that is proportional to the vibration of the system.3.2 Units of measureUnits of measure
42、shall be as given in the definitions found in Section 3.1. In the text and examples, SI (metric) units of measure are given as primary units followed by IP (inch-pound) units of measure.3.3 SymbolsSymbols used in this standard are identified/defined where they are presented in pertinent equations.Fi
43、gure 3.1Vibration Cycle4 | ANSI/AMCA 204-05 (R2012)4. Application CategoriesThe design/structure of a fan and its intended application are important criteria for categorizing the many types of fans in terms of applicable and meaningful balance quality grades and vibration levels.Table 4.1 categorize
44、s fans by their application and driver power to arrive at appropriate Balance and Vibration (BV) application categories.A fan manufacturer will typically identify the appropriate application category based on the type of fan and power. A purchaser of a complete fan assembly may be interested in one
45、or more of the following: the Balance Grade (Table 5.1), vibration as tested in the factory (Table 6.2), or vibra-tion in-situ (Table 6.3). Typically, one Balance and Vibration category will cover both the application and the driver power considerations. However, a purchaser may request a Balance an
46、d Vibration category different from the one listed for the application and driver power considerations. Some may desire a more precise balance quality grade or lower vibration level than is typical for the application. In most cases, the Balance and Vibration category, the balance quality grade and
47、vibration limits must be agreed upon as part of the contract for the fan. In the event that no such agreement exists, fans purchased as being required to comply with this standard shall meet the Table 6.2 vibration limits (assembled fan) or the Table 5.1 residual unbalance requirements (unassembled
48、fan or rotor assembly only).The purchaser may contract for a particular mounting arrangement to be used for factory testing of an assembled fan in order to match (as nearly as possible) the planned in-situ mounting at the job site. If no specific contract on balance/vibration exists, the fan may be
49、mounted either rigidly or flexibly for the test, regardless of the in-situ mounting.5. BalancingThe fan manufacturer is responsible for balancing the fan impeller to acceptable commercial standards. This stan-dard is based on ANSI S2.19 (ISO 1940). Balancing done in conformance with this standard shall be performed on a highly sensitive, purpose-built balance machine that permits accurate assessment of residual unbalance.Application Examples Driver Power kW (hp) LimitsFan Application Category, BVResidential Ceiling fans, attic fans, window AC 0.15 (0.2) 0.15 (0.2)
