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gearbox information
Torque Ratings
All gearbox torque fi gures have been reproduced to represent an accurate output fi gure. These fi gures may be affected by tolerances created
during production techniques as well as application circumstances once the units have been installed. A margin of + or - 10% should be taken into
consideration on these fi gures during your selection of an appropriate unit.
Gear units
Worm gear units: The output shaft is pressed into gear wheels of composite or bronze, with hardened and polished steel worms.
Worm/spur gear units: The drive pinion comprises either a composite or bronze worm gear with a pressed steel helical pinion insert driving a
spur steel gear train rotating on intershafts. The fi nal gear is pressed and keyed onto the fi nal shaft.
Spur units: The steel pinion drives helical/spur cut steel gears rotating on intershafts. The fi nal gear is pressed and keyed onto the fi nal
shaft.
Planetary units: The composite drive pinion drives a series of steel secondary gears.
Gearbox and quality ball bearings are packed with an appropriate grade of NLGI 1/2 grease as standard. All units are sealed for life utilising `O'
rings on all key mating surfaces and are suitable for running in any mounting position.
Gearbox positions
Alternative positions for the gearboxes can be arranged to suit customer requirements but unless specifi ed, will be supplied in standard position
as shown on the individual drawings. This also applies to the gearbox shaft extensions.
Lubricants
Parvalux gearboxes are charged as standard with NLGI 1/2 rated grease and are sealed and lubricated for life. In certain conditions, Parvalux
gearboxes may be fi lled with multi-grade (20/0) oil or semi-fl uid grease and sealed for life. Working temperatures of lubricants: -
Grease: - 1°C to +120°C
Oil: - 1°C to +10°C
Single and double worm reduction gearboxes
Whilst worm gearing has lower effi ciency than spur gearing it is true to say that generally the noise level of worm gear reduction is much lower
and therefore, where noise is an important factor, this type of gearing should be considered. To prevent premature gear failure or excessive gear
wear, the maximum gear loading and thermal rating of the particular gearbox must be taken into consideration; otherwise there is a danger of
stripping the gear wheel teeth or failure of the lubrication due to excessive gearbox temperature. If further information is required on this point
please consult our sales engineers.
Testing
To B.S. Specifi cation 000 Part II. All our units are CE marked and comply with current regulations/directives at time of printing.
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