Balancing a Grinding Wheel. Grinding Wheel Balancing

In the grinding operations section, this article’s topic is balancing a grinding wheel. How is a grinding wheel balanced, why is balancing a grinding wheel necessary, and what happens if a grinding wheel isn’t balanced — we’ll cover these topics.

Why is balancing a grinding wheel necessary?

It’s necessary to periodically balance a grinding wheel. This is because operations performed with an unbalanced grinding wheel result in the following:

• If the grinding wheel is unbalanced, surface quality decreases due to vibration marks.
• Dimensional accuracy on workpieces decreases.
• The time spent on wheel dressing increases.
• If the grinding wheel isn’t balanced, the wheel wears out faster and its service life decreases.
• If working with an unbalanced grinding wheel, wear occurs on the spindle. Extra time and cost are required for inspections and repairs.

As a result, if grinding wheels are not balanced, this causes a decrease in workpiece quality and work efficiency.

How is balancing a grinding wheel done?

Specially prepared balancing stands are available for balancing a grinding wheel, but two precisely machined pieces placed on a plate whose levelness has been checked with a spirit level can also serve as a balancing stand. The wheel to be balanced is mounted lightly and without forcing onto the wheel arbor.

Since some balancing stands are manufactured specifically for this purpose, they have their own spirit level and balancing adjustment screws.

For static balancing, the wheel placed on the balancing stand is lightly turned by hand and allowed to come to rest. If the wheel is unbalanced, it will rock back and forth for a while and then stop at one point.

The heaviest point of the wheel, which is resting motionless on the stand, is marked along the vertical axis at its lowest position.

There are three balancing weights on the grinding wheel flange that can move along a groove.

By sliding the balancing weights within the groove, the imbalance in the center of mass is corrected by repositioning these balancing weights.

The wheel is placed back on the balancing stand and released in different positions. If the wheel stays put in every position, it means it’s balanced. Once balancing is complete, the wheel’s balancing weights are checked once more and securely tightened, after which the wheel is mounted on the machine’s spindle.

A wheel that has been statically balanced will, over time and with use, wear down and lose some of its diameter, inevitably throwing off its balance, and a proper grinding operation will no longer be possible. For this reason, the wheel should periodically be removed from the machine’s spindle and rebalanced.

Video: how is grinding wheel balancing done

Dynamic Balance Adjustment

Dynamic balancers that perform automatic balancing for grinding machines are also available. In this system, the heavy portions of the wheel are identified from indicators on both sides of the system. Weight differences are distributed evenly around the circumference of the wheel by means of balancing weights. Very precise balancing is possible with this system

The system works on the principle of mass compensation for wheel imbalance. There are two movable eccentric weights in the balancing head; each weight is driven by electric motors through a precision gear mechanism. These weights can be repositioned to compensate for any imbalance in the grinding wheel.