Hot Rivet Peening Eliminates Distortion in Aerospace Bearing Cages
A ball bearing manufacturer was experiencing plastic deformation of a two-piece aluminum bronze bearing retainer when riveting the two halves together.
The rivet diameter increased as it was peened. Initially the rivet filled the rivet hole as expected. As the steel rivet head was peened further, to the produce the required head diameter, the rivet deformed the softer cage material.
This deformation caused the bearing cage to develop high spots around each rivet. These high spots would rub against the outer bearing race and generate debris as the bearing operated.
A custom servo press was developed to implement hot rivet peening.
The servo press uses an electric power supply pass current through the rivet and heat it so that the head forms easily.
As the rivet is heated it loses strength and the compressive force drops. Once the force drops to a pre-determined value, the servo press presses the rivet to a position. This creates the required rivet head diameter without any retainer distortion.
If you have a need for a custom servo press contact us or call today at 603.386.5300