AS 3709-1989

1 - AS 3709-1989 VIBRATION AND SHOCK-BALANCE QUALITY OF ROTATING RIGID BODIES
4 - PREFACE
5 - CONTENTS
6 - 0 Introduction
6 - 1 Scope and field of application
6 - 2 References
7 - 3 Pertinent aspectsof the balancing problem
7 - 3.1 Representation of a state of unbalance
7 - 3.2 Unbalance effects.
7 - 3.3 Rotors with one correction plane.
7 - 3.4 Rotors with two correction planes
7 - 3.5 Assemblies
7 - 4 Permissible unbalance related to rotor mass
9 - 5 Quality grades relating service speed and permissible residual specific unbalance
9 - 6 Determination of balance quality requirements
9 - 6.1 General
9 - 6.2 Balance quality requirements based on established grades
9 - 6.3 Balance quality requirements based on experimental determination
9 - 6.4 Balance quality requirements based on specified permissible bearing forces
12 - 7 Allocation of permissible residual unbalance to each correction plane on the basis of Uper
12 - 7.1 General
12 - 7.2 Single-plane balancing
12 - 7.3 Two-plane balancing
12 - 7.3.1 General
12 - 7.3.2 Simplified approximate methods
14 - 7.3.3 General methods
15 - 8 Determination of the residual unbalances
15 - 8.1 Determination with a balancing machine
15 - 8.2 Determination by means of an amplitude- and phase-measuring device
15 - 8.3 Determination by measurements taken with a measuring device without phase indication
16 - 9 Sources of errors in balancing
16 - 9.1 Instrument “read-out” errors
16 - 9.2 Errors due to the drive and auxiliary equipment
19 - Annex - Example for the general method described in 7.3.3.1 for two-plane balancing

Gives recommendations for determining unbalance and for specifying related quality requirements of rigid rotors. It specifies a representation of unbalance in one or two planes, methods for determining permissible residual unbalance, methods for allocating it to the correction planes, methods for identifying the residual unbalance identification. It is identical with and has been reproduced from ISO 1940-1:1986.

This part of ISO 1940 gives recommendations for determining unbalance and for specifying related quality requirements of rigid rotors; it specifiesa) a representation of unbalance in one or two planes;b) methods for determining permissible residual unbalance;c) methods for allocating it to the correction planes;d) methods for identifying the residual unbalance state of a rotor by measurement;e) a summary of errors associated with the residual unbalance identification.In table 1 and figure 2 recommendations are given, based on worldwide experience, concerning the balance quality requirements of rigid rotors, according to their type, mass and maximum service speed.This part of ISO 1940 is also intended to facilitate the relations between manufacturer and user and machines. Terminology specified in this part of ISO 1940 may be used for establishing technical specifications. (For definitions, see ISO 1925.)Detailed consideration of errors associated with the determination of residual unbalance is not included in this part of ISO 1940 (ISO 1940/2 will deal with these errors). This part of ISO 1940 does not define permissible residual unbalances for flexible rotors; these are covered in ISO 5343. The methods for balancing are not described.The recommended balance quality grades are not intended to serve as acceptance specifications for any rotor group, but rather to give indications of how to avoid gross deficiencies as well as exaggerated or unattainable requirements; they may also serve as a basis for more involved investigations, for example, when a more exact determination of the required balance quality by measurement in the laboratory or in the field is necessary. If due regard is paid to the recommended limits, satisfactory running conditions can most probably be expected. However, there may be cases when deviations from these recommendations become necessary, e.g. because of unusual construction or geometry.