Electric Motor Balancing Standards

Description and discussion is a review of api shop balancing methods as well as a review of iso standards related to shop and field balancing that are referenced by api standards.

Electric motor balancing standards.

The degree to which a motor is out of balance. Electric motor balancing at hi tek balancing is performed by mounting the entire motor on a balancing fixture. Balance grade g2 5 is recommended for steam turbines machine tools and small electric armatures. Many motor failures are mechanical and associated with the rotor and bearings so balancing has a direct effect on the life of the motor and productivity.

Larger g numbers cause more structural stress. Based on experimental data the potential for damage is proportional to the balancing quality grade. How motor rotor balancing affects motor life. Subcommittee sc 1 balancing including balancing machines.

Part 1 and by german standards as vdi 2060. Rigid rotors only example. Specification and verification of balance tolerances gives specifications for rotors in a constant rigid state according to their machinery type. Balance grades balance grades are used to specify the allowable residual imbalance for rotating machinery.

This second edition cancels and replaces the first edition iso 1940 1 1986 which has been technically revised. The most important change is the introduction of reference planes for balance tolerances instead of using the correction planes as tolerance planes. Easa standards dated february 1995 section 2 page 2. Iso 1940 1 requires an understanding of balancing and its terminology if the standard is to be understood and.

The easybalance software has a built in balancing quality calculator for iso mil api and special standards like 4w n and such. Adopted by the american national standards institute ansi as s2 19 1975 balance quality requirements of rotating rigid bodies it has also been adopted by british standards as bs 6861. The electric motor balancing fixture is equipped with. The iso 1940 standard defines balance grades for different classes of machinery.

This reads as follows dynamic balancing should be to the level specified by the customer. The motor shaft is rotated by an external motor to ensure that the only contributions to the vibration data is the dynamic unbalance of the motor and not it s operating noise. In the absence of a requested level dynamic balancing to balance quality grade g2 5 iso 1940 1 should enable the machine to meet final vibration limits as defined in 6 4 6 reference. In this post we will examine balancing standards and how you can ensure you get a quality repair.