GEARED POWER TRANSMISSION UNITS

Oil-lubricated totally enclosed gear reducers and increasers shall be provided.

Service Ratings

Each gear shall have a nameplate service power rating equal to the nameplate rating of the driving motor. Each gear shall have mechanical and thermal capacity equal to or greater than an equivalent power determined by multiplying the service power rating by the specified service factor recommended by AGMA for heavy duty service, except each set of worm gears shall have a minimum service factor of 1.20 and all other gears shall have a minimum service factor of 1.50.

Thermal Rating

Thermal rating for the equivalent power shall be obtained without auxiliary cooling equipment such as heat exchangers. Units shall be designed to operate continuously for the conditions specified in a location where ambient temperatures vary from 7oC to 55oC, and metal surfaces in direct sunlight can reach 85oC. Data for any gear reducer/ increaser requiring a cooling coil shall be submitted to the Engineer for approval. If a cooling coil is require, provided minimum 25mm diameter tubing and a 25mm solenoid supply water valve with the gear.

Bearings

Anti-friction bearings shall be provided throughout, designed to give minimum 20000 hours B10 life for the specified power in continuous operation consistent with acceptable modern practices for applied radial and thrust loads at the speeds involved. Provide thrust bearing rates at 1-1/2 times the maximum thrust loadings involved.

Gear Nameplates

Each geared power transmission unit shall be equipped with an AGMA nameplate which shows service power, actual service factor for actual mechanical or thermal rating as applicable, and AGMA gear Class I rating.