Nexen RPS16G-C0070T/360-EP2U 966554 - Manual (Page 6)

FORM NO. L-21252-B-1209 6
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• RPG solid ring gears are available in diameters up to approximately 750 mm [29.5 in.], beyond this the ring gears
will consist of segments that will be joined together to form a complete ring. Arcs of various radiuses and lengths
can also be provided. Throughout this document “ring gear” will be used primarily but will also apply to arc segments
unless otherwise noted.
• CAUTION Handle the ring gear or arc segments with care they are very high precision products. Do not drop, allow
anything to fall on, or place them on non-flat surfaces.
• The ring gear ID, OD and the side without product numbers are reference surfaces. The side with the part number
on it should be away from the machine bed mounting surface.
• Secure the ring gear using all of the available bolt holes. Refer to Table 1. This will ensure the highest degree of ring
gear stability.
• Install the RPG system at the temperature at which it will be used.
• The ring gear teeth are hardened on the tooth faces only.
• If the gear is segmented, a special alignment tool is required to properly join the segments together and is available
from Nexen. The alignment tool ensures proper pinion meshing and system accuracy when the pinion crosses gear
joints. For full segmented rings an alignment tool for every joint is recommended, for arcs one aligment tool is required.
To use the alignment tool a special mounting hole provision is required in the machine bed off to the side of where
the gear segments meet to temporarily secure the alignment tool. When the adjacent gear segments are properly
positioned, there will be a 0.1 - 0.2 mm gap between their ends. See Figures 1, 2, and 4 for details.
• If the ring gear rotates in the vertical plane, take precautions to prevent debris and contaminates from collecting on
the ring gear since it could interfere with pinion meshing. In such environments, it is recommended that the ring gear
be shielded and / or locate the pinion around the lower half of the ring gear to allow debris to fall out of the tooth
pockets before reaching the pinion.
P
inion
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equirementS
• Verify the shaft variance and diameter tolerances meet Nexen specifications before mounting the pinion. See Figure
10.
• The shaft on which the pinion is mounted on must pass all of the way through the pinion and bushing for proper sup-
port.
• If using a flange mount pinion, verify that the dimensions and tolerances of the gearhead flange meet the specifica-
tions of the ISO 9409 Standard.
• Mount the pinion as close to a support bearing as possible to minimize shaft deflection.
• The pinion roller bearings are sealed. It is still recommended, however, that the pinion be shielded from liquids, dust,
and debris.
• Multiple pinions can drive a gear without an additional service factor but the load sharing by each pinion must be
equal. This is best accomplished with discrete drives linked electronically; mechanically linking pinions is not recom-
mended. Contact Nexen for more information.
• The RPG system can be operated such that the pinion revolves around the ring gear as long as the pinion preload
remains within specifications as it revolves.
SYSTEM DESIGN OVERVIEW