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2. The size of the rotary table is taken from the __________
of the opening in the table.
3. The ____________ is factory-aligned, or equipped with
self-aligning bearings, to prevent required adjustment of the
contact with the main gear in the field.
4. The ____________ is an alloy steel casting on which the
ring gear and upper race of the main bearing are shrunk.
5. The present-day ring gear is spiral ____________, as
compared to the earlier straight bevel gear.

Exercise 5. Point out true or false
1. The overlapping action of the teeth tends to eliminate
shock and provides a smoother running machine.
2. Recesses are provided in the bushing for a lifting hook to
facilitate handling on the rotary table.
3. The bearing is supported by two roller bearings mounted
near the respective ends.
4. The main base, in addition to serving, as an oil sump,
provides support for the table casting, through the main bearing,
and for the pinion shaft assembly.
5. Most rotaries take their power through the drawworks, by
means of chains and pinions, from the primary engines.

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