Only the geometry. The gearing is the same helical type with the same efficiency, but the output shaft is offset parallel to the motor rather than on its centreline. That makes the assembly shorter along the axis and lets it sit beside the driven equipment. Choose between them on layout and available space, not on performance, since neither has an efficiency advantage over the other.

Because the combination of a parallel offset and a hollow output shaft suits the geometry of a conveyor drive exactly. The gearmotor slides onto the drum shaft, sits alongside the frame rather than projecting into the walkway, and is held by a simple torque arm. There is no bedplate to fabricate, no coupling to buy and no alignment to hold, which removes both cost and a recurring maintenance issue.

It stops the gearmotor housing rotating around the driven shaft. With a hollow shaft mounting, the unit is carried by the shaft itself, so the only additional restraint required is a link from the housing to a fixed point that reacts the torque. It should allow some movement and be fitted with the specified rubber or spring element where one is called for, since a rigidly bolted arm transmits shock into the gearcase.

A clamping assembly that grips the driven shaft by friction rather than through a key, tightening onto the hollow output shaft to lock the two together. It removes the small amount of lost motion a keyed fit permits, spreads load around the whole circumference instead of concentrating it at the keyway, and makes removal easier after long service. It is preferred where reversing or shock loading is present.

No. Both use helical gearing at similar efficiency per stage, typically in the mid to high nineties per cent, and both are far more efficient than worm units. Any difference between two specific products will come from the number of stages and the quality of the design rather than from the parallel or in-line arrangement itself. Compare the actual figures for the units under consideration.

With difficulty if nothing was done at installation, which is why anti-seize compound on the shaft and correct use of the supplied removal provisions matter. Many hollow shaft units include a threaded extraction arrangement for exactly this purpose. Shrink disc mountings generally release more cleanly than keyed fits, which is a further argument for them on drives expected to be serviced.

Belt and chain conveyors, screw conveyors, agitators and mixers, bulk material handling, waste and recycling equipment, and process plant where the drive must sit close alongside the shaft it turns. Anywhere a long in-line assembly would obstruct access or foul structure, and where continuous running makes the efficiency of helical gearing worth having over a right-angle worm alternative.