 On the roof of the US Capitol flags are flown, packaged, and given as gifts by Congressmen. A crane is needed to raise and lower carts of flags. The existing 1970s structure had a load capacity of 500 lbs. Although it had been load tested periodically, it was not OSHA compliant. Left unprotected, it aged outside causing safety concerns.
In January of 2007, Zenmar began working with a Structural Engineer discussing options for replacement of the old Flag Hoist. After an extensive exploration of options, a Gorbel ‘Sleeve Mounted’ Freestanding Jib Crane with a ½ ton capacity was chosen. It was fitted with a Harrington Electric Chain Hoist and Motorized Trolley.
The new flag hoist design improvement increased capacity and reach. The Motorized Trolley provided superior hook positioning. The Power Rotation Drive offered more control and safety including ‘Soft’ Starts and Stops that eliminate swinging loads. A new foundation was built on the sub-roof level of the Capitol allowing a narrow footprint of the crane on the roof’s surface and thus more foot traffic near the mast. The structure was painted “US Capitol” White.
During installation, Zenmar protected the features of this historic building, including its soldered copper roof. Plywood was laid over the work area. We used a manually operated material lift and an adjustable aluminum gantry crane to minimize impact on the building itself. The new jib crane was loaded at Zenmar on a stake-body truck. Upon delivery, a mobile crane placed each piece on the roof.
Through much hard work, Zenmar assembled the system and festooning. An 8 Button Pendant was hooked up to control operation of the crane. After finalizing controls and electricity, Zenmar performed an ANSI Compliant Load Test of the crane system. This constitutes raising a load 125% of capacity and carrying it through the complete range of motion. To complete the project, Zenmar offered formal training to those using the crane in their daily work.
Zenmar was the first to put the new Capitol Flag Hoist to use. We used it to lower all of our equipment, tools and plywood down to the terrace level of the Capitol. We then packed up and went home after 3 full days of work.
If you would like more information about this application or have an application of your own you would like us to look at, please let us know. We can be reached at 410-785-5790. Thank you.
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