300 Ton Crane Facts:


Bridge Span: 75'-0"

Bridge Girder Depth: 10'-0"

Bridge Weight: 249,000 pounds

Bridge Drives: 4 @ 15 hp each with rotating axles

CMAA Class: "D"
300/165 Ton Trolley Hoist Facts:


True Vertical Lift: 37'-0"

Trolley Gage: 24'-0"

Weight: 150,000 pounds

Main Hoist : 150 hp

Auxiliary Hoist: 125 hp

Trolley Wheels: 8 @ 24" diameter

Trolley Drives: 2 @ 15 hp each with rotating axles

Profile: 48" over bridge low- headroom design
Equipment Features :


Bridge and hoist service platforms

Horizontally-split gear boxes

Encapsulated bearings

Oversized load hooks

All gearing enclosed
Prior to this project, the best controls on the market were capable of 1,000:1 speed control. This means that the slowest controllable speed would be 1/1000 of the maximum speed. With a top speed of 120 fpm, the slowest controllable speed would have been 0.002 feet-per-second, far to fast to achieve the required incremental moves of 0.002 inches. Closed-loop-flux-vector controls with special pulse-counting software was utilized to achieve the client's desired control. Each motor was outfitted with an encoder and its own individual flux-vector drive.