AS 3721-1989

1 - AS 3721-1989 VIBRATION AND SHOCK-BALANCING MACHINES-DESCRIPTION AND EVALUATION
4 - PREFACE
5 - CONTENTS
6 - 1 Scope
6 - 2 Field of application
6 - 3 References
6 - 4 Capacity and performance data of the machine
7 - 4.1 Capacity and performance data of horizontal machines
7 - 4.1.1 Rotor mass and unbalance limitations
8 - 4.1.2 Rotor dimensions
8 - 4.1.3 Drive
9 - 4.1.4 Couple unbalance interference ratio
9 - 4.1.5 Air pressure requirements:
11 - 4.2 Capacity and performance data of vertical machines
11 - 4.2.1 Rotor mass and unbalance limitations
11 - 4.2.2 Rotor dimensions
12 - 4.2.3 Drive
13 - 4.2.4 Couple unbalance interference ratio
13 - 4.2.5 Air pressure requirements:
15 - 5 Machine features
15 - 5.1 Principle of operation
15 - 5.2 Arrangement of the machine
15 - 5.3 Indicating system
15 - 5.3.1 Amount indicators
15 - 5.3.2 Angle indicators
15 - 5.3.3 Operation of the indicating system
15 - 5.4 Plane separation system
16 - 5.5 Setting and calibration of indication
16 - 5.5.1 Soft-bearing machines
16 - 5.5.2 Hard-bearing machines
16 - 5.6 Other devices
16 - 6 Minimum achievable residual unbalance
16 - 7 Production efficiency
16 - 7.1 Time per measuring run
17 - 7.2 Unbalance reduction
17 - 8 Performance qualifying factors
17 - 9 Installation requirements
17 - 9.1 General
17 - 9.2 Electrical and pneumatic requirements
17 - 9.3 Foundation
17 - 10 Proving rotors and test masses
17 - 10.1 Proving rotors
23 - 10.2 Test masses
25 - 11 Verification tests
25 - 11.1 Requirements for three tests
25 - 11.2 Duties of manufacturer and user
25 - 11.3 Requirement for weighing scale
25 - 11.4 Test and rechecks
25 - 11.5 Balancing speeds
25 - 11.6 Test for minimum achievable residual unbalance
27 - 11.7 Unbalance reduction test
27 - 11.7.1 Aim of test
27 - 11.7.2 Test procedure
27 - 11.7.3 Readings
27 - 11.7.4 Preparation of test sheets
28 - 11.7.5 Unbalance reduction test runs
28 - 11.7.6 Plotting the test data
28 - 11.7.7 Evaluation of plotted test points
28 - 11.7.8 URR tests on single-plane balancing machines
28 - 11.7.9 Test for couple unbalance suppression on single-plane machines
28 - 11.7.10 Special URR limit circle diagram
33 - Annex A - Information to be supplied to the balancing machine manufacturer by the user
33 - A.1 Rotors to be balanced
35 - A.2 Other requirements
35 - A.3 Administrative requirements
36 - Annex B - Definitions
36 - B.1 specific unbalance (mass eccentricity, e)
36 - B.2 correction plane interference:
36 - B.3 correction plane interference ratios:
36 - B.4 unbalance reduction ratio (URR):
36 - B.5 minimum achievable residual unbalance,
36 - B.6 claimed minimum achievable residual specific unbalance
37 - Annex C - URR limit diagrams
37 - C.1 General
37 - C.2 Basic data
37 - C.3 Instructions for drawing URR limit circles diagrams
38 - C.4 Instructions for calculating URR limit circles
40 - Annex D - ALTERNATIVE METHOD FOR PROVING ROTORS FOR HORIZONTAL MACHINES

Sets out standards for the evaluation of performance and characteristics of machines for balancing rotating components where correction is required in one or more planes perpendicular to the shaft axis. It stresses the importance attached to the form in which the balancing machine characteristics should be specified by the manufacturer and also outlines methods of balancing machines. Guidance on the manner in which users should state their requirements is given. Technically identical with ISO 2953.

This International Standard sets out standards for the evaluation of performance and characteristics of machines for balancing rotating components where correction is required in one or more planes perpendicular to the shaft axis. It stresses the importance attached to the form in which the balancing machine characteristics should be specified by the manufacturer and also outlines methods of evaluating balancing machines. Adoption of the format suggested in 4.1 and 4.2 makes it easier for the user to compare one manufacturer's product with another's. Guidance as to the manner in which users should state their requirements is given in annex A.It should be noted that the terminology used throughout this International Standard is in accordance with ISO 1925 and this terminology should be employed by manufacturers and users when applying this International Standard.Field of applicationThis International Standard is applicable to balancing machines that support and rotate rigid workpieces (that is, workpieces that are rigid at balancing speeds) and that indicate the amounts and angular locations of unbalance corrections required.It covers both those machines that measure out-of-balance effects on soft bearings and those that measure out-of-balance effects on hard bearings. It also relates to resonance-type machines, provided that mechanical compensators are incorporated.Technical requirements for such balancing machines are also dealt with; however, special features, such as those associated with automatic correction, are excluded.Details of proving rotors, test masses and performance tests to be employed to ensure compliance with specified unbalance indicating capability are given. Tests for other machine capacities and performance parameters are not contained in this International Standard.Annex A gives an indication of the information a user might supply to a manufacturer and a suggested method of tabulating it. Annex B gives some of the definitions relevant to the provisions of this International Standard.This International Standard does not specify balancing criteria; these will be found in ISO 1940.