4 reduction-drive gearbox, 1 general description, Reduction-drive gearbox – CAT Titan 250 User Manual
Page 14: General description, Figure 5
 
Turbomachinery Package Specification
Titan
250 Generator Set
4 Reduction-Drive
Gearbox
4.1 General
Description
The reduction-drive gearbox (Figure 5) is an industrial, epicyclic, star-gear design 
selected specifically for generator set applications. The gearbox uses few moving parts, 
which provides high reliability and ease of assembly and disassembly. The reduction 
gearbox is designed for continuous-duty operation and reduces the output speed of the 
turbine to the required operating speed of the generator. The gearbox is coupled to the 
gas turbine through a balanced high-speed shaft, splined at both ends. The output shaft 
is coupled to the generator through a flexible disk-type dry coupling enclosed in a 
coupling guard. The design of the gearbox facilitates straight-through shafting, avoiding 
offset problems and permitting engine, gear, and generator alignment from a common 
base. Gear lubrication is provided by the package lube oil system. 
The gearbox is designed to provide 99% reliability between major inspections and 
overhauls. 
Figure 5. Typical Reduction Gearbox for the Titan 250 Generator Set
Table 2.
Reduction-Drive Gearbox Specifications
Approximate Weight
Gearbox
7300 kg (16,100 lb)
Output Speed 
50 Hz Service 
1500 rpm
60 Hz Service
1800 rpm
Inspection and Overhaul Intervals
Major Inspection Interval
30,000 hours
Overhaul Interval
100,000 hours
Compliance
American Petroleum Institute (API)
613 Compliant With Exceptions, Refer to Solar’s 
Standard List of Exceptions 
Ratings
American Gear Manufacturers Association 
(AGMA) 
In Excess of 1.10 for Generator Applications
Vibration Monitoring
Gearbox Acceleration
Probe
© 2008 Solar Turbines Incorporated. All rights reserved.
TPS250GS/908 - Preliminary
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