Unusual Noise or Motion

Basic Troubleshooting Unusual Noise or Motion

Direct drive units with two motors check motors spin in opposite directions (counter-rotate).
Units with bearing noise check stroke, RPM and timing.
On sympathetic units, check isolation springs and mounts.
Check dive springs, reaction springs and rocker arms.
Check for interference with stationary structure.
Check removable bolt on parts are properly secured.

More Information On Unusual Noise or Motion

More Information Unusual Noise or Motion

Direct drive vibratory motors create a force that is transmitted to the frame through the motor base. When two motors are used it is to direct the movement to convey or screen. The motors must counter rotate to provide directional movement. To reverse motor rotation, swap any two of the phase wires where they connect to the motor input in the motor junction box.

Some bearing noise is normal, excessive noise could be a knocking sound that was not present previously. Bearing noise is often caused by high bearing loads. Running stokes lower or higher than design increases load on the bearings. Running RPM different from design can change stroke and affect bearing load. Correct the pan and balancer stroke / RPM to reduce bearing load.

Check Motor Direction

Feeders or other equipment with two direct drive motors require a counter rotating configuration. Note when viewed from the top one motor is spinning clockwise and the other is rotating counterclockwise. To switch motor rotation direction: switch any two phase wires. Check equipment general arrangement drawing, if a motor direction is shown it must be adhered to.

Over or under greasing can cause increase bearing wear. Consult the equipment user manual for type of grease and schedule.

Broken isolation springs / mounts on sympathetic units will cause unusual motion. The isolation mounts are part of a dynamic system if a spring or mount brakes or is damaged the uneven support can make the machine move excessively or in undesired directions.

Broken drive or reaction springs can cause undesired movement. Rocker arms are part of the spring rate as well as movement control. The rocker arm clips need to clamp tight onto the bushings to provide the designed control. Rocker arms should rotate about bushings, not move up down or side to side. If a rocker arm feels like it’s being hit with a hammer while the others around it do not have an impact that can be felt in the body. Check the bushing, bolt tightness and clip clamping of that arm with the impacting that can be felt. If bushings are worn or clips do not clamp bushings tight repairs need to be made.

Rocker arm and reaction spring of typical unbalanced shaft driven conveyor.

Damaged or missing components should be replaced immediately. Moving parts need free space to operate. If infeed equipment, structure or anything else can crash into pan, balancer or any other moving part machine damage may occur. Operating clearance should be checked before first start, after changes are made and periodically throughout the life of the equipment. Bolt in load decks, screens, hoods, skirts, discharges or diverters need to be affixed tightly to prevent damage. Address loose or missing fasteners.