Lambert fits Schmitt AEMS into Bryant grinder

Lambert recently won an order to rebuild a Bryant grinding machine for Revolvo, a midlands-based manufacturer of large and split bearings.

The machine has been installed at Revolvo's new premises in Dudley.

The high accuracy and repeatability demanded on a rebuilt Bryant grinding machine required an acoustic emission monitoring gap and crash control system from Schmitt Europe.

The high accuracy and repeatability demanded from the machine meant that Lambert chose to incorporate an AEMS (Acoustic Emission Monitoring System) gap and crash control system from Coventry-based Schmitt Europe.

The Bryant LL3 machine was upgraded with CNC control and new software developed in conjunction with Revolvo.

The grinder is capable of outside diameter (OD), inside diameter (ID) and track and lip (Vector) grinding of roller bearings from 50 to 450mm diameter.

The machine has a point wheel dresser unit as standard and has also been retrofitted with a custom-made radius dressing attachment capable of generating gothic-arch wheel profiles.

The machine was originally fitted with a spindle load meter, but retro-fitting with the Schmitt AEMS means that a slide-tube type acoustic sensor mounted inside the grinding spindle can now detect the grinding wheel touching the workpiece or diamond dresser within one millisecond.

This data is sent back via Schmitt's SB-4500 series electronics to the machine control.

The AEMS allows rapid grinding wheel in-feed right up to the point of initial contact with the part, saving considerable air grinding time (non-cutting time) and therefore reducing overall cycle times.

The Schmitt controller also gives a graphical output of noise levels during the grind, so the operator can see what is happening throughout the process in a user-friendly format.

The AEMS can monitor and safeguard against crash conditions occurring on the machine by sensing heavy contact between the abrasive wheel and bearing surface, or other part of the machine.

AE monitoring has also become an integral component in the dressing of abrasive wheels, especially CBN, where it is essential to remove as little material as possible.

The wheel profile can be plotted on screen during a dress, giving a picture of what is occurring on the wheel surface.

The slide-tube acoustic sensor uses non-contact technology and is telescopic to facilitate installation.

It sits inside a bore within a grinding-machine spindle or rotary diamond dresser.

This configuration allows the acoustic sensor to spin with the spindle and means it is in close proximity to the grinding event, giving a clear and uninterrupted signal.