The Oilgear Company was selected as a subcontractor to supply both the hydraulic- and electronic-control components of the Knapp Street Bridge, in Milwaukee, Wisconsin. The fact that Oilgear could functionally serve as both a mechanical and an electrical subcontractor meant that traditional coordination challenges between the two disciplines would be eliminated by selecting a single source that could deliver both Hydraulic and Electronic engineering and manufacturing functions.
The bridge has a dead load of 735,000 lb, about 89% of which is leveraged by counterweights when raised. Oilgear's hydraulics effectively lift the remaining 11% (79,000 lb) to a height of 12 ft 3 in. A 100-hp main motor is accompanied by a 25-hp emergency drive.
In accordance with Oilgear's performance assurance program, the entire hydraulic/electronic system underwent an exhaustive factory system test at Oilgear's facility prior to installation on the bridge.
The system was fully piped and wired on the shop floor, and using various devices Oilgear conducted a simulation of the bridge's operation for the customer.
Following a successful demonstration, Oilgear adhered to a strict shipping timeline designed for optimal efficiency at the work site. Once the system was all piped and wired on the bridge itself, it took Oilgear just one week to commission the bridge according to the project's specifications.