Trolley beam

EXHIBIT 6-46 Fixed Structure with a Trolley Beam... 

Because furnace tubes must be periodically replaced, clear areas are provided directly in line with the tubes. The removal mechanism may be a trolley beam located on the stack of a circular furnace, a crane, or a cherry picker. If only one or two tubes require removal, a tube extraaor, similar to the type used for extracting shell and tube exchanger bundles, may be used. As can be seen in Exhibit 7-l6, radiant... 

Handling sucii removable items as relief valves and valve drives for off-site repair and catalyst loading can be achieved by fixed handling devices or by mobile equipment. Fixed handling devices can be davits or, for structure-mounted reactors, trolley beams. Exhibit 9-25 depicts a typical davit arrangement, and Exhibit 9-26 shows a trolley beam arrangement. 

Jling of these iieras is achieved by fixed devices (e.g., iavits or trolley beams) or by mobile equipment (e.g., ranes). When davits or beams are used, they are lo-rated at the top of the tower, accessible from a platoon, and designed to lower the heaviest removable tern to a designated drop area at grade. When mobile xjuipment is used, a dear space must be provided at... 

Hitch points and trolley beams are also required to facilitate maintenance. The lifted load requirement should be indicated on the layout drawing (as shown in the structure cross section in Exhibit 12-24) to show the maximum weight to be lifted at that point for the... 

A two-level structure is shown in Exhibit 12-20. The exchanger tube bundle maintenance on level I is the focal point of this exhibit The size of the exchanger to be maintained determines the need for a tube removal structure. If such a structure is required, it should have a beam direaly opposite the exchanger from which the bundle can be pulled. The struaure must also have a trolley beam across the top of the upper level and directly over the exchangers. If a tube removal struaure is not used, a trolley beam located direaly over the channel end of the exchangers on level I... 

Monorail High capacity load blocks suspended from trolleys which traverse monorail beams suspended from boiler support steel. Provides capability to lift and move loads within boiler cavity. 400 (363)... 

This is especially useful for carrying light materials, such as fluffy powders, over long distances throngh dncts that can be taken around obstacles or walls or support columns/beams, where it may be difficult to use overhead travelling cranes, belt conveyors or rail tracks (for carrying trolleys). 

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