General purpose DC motors produce a constant torque (where torque is the measure of a rotational or twisting force) throughout their speed range making them ideal for use when the load is not significantly altered by the speed and provide full-rated torque at low rpms in conveyor belts, hoists, mixers, and positive displacement pumps. They have ball bearings that can handle heavier radial and axial loads due to the high torque that DC motors can produce. Motors are designed for mechanical loads and for hard-to-start applications such as conveyors, belt-driven equipment, machine tools, mixers, positive displacement pumps, and reciprocating pumps.