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It may happen that who designed the structure did not think that you need to place that beam or frame as soon as possible, because no weight should be hanging from the hook waiting for you to weld pieces that support that structure or place anchorages into the concrete, etc.
You should be allowed - by design and by schedule - to release the weight and release the crane and slings just when the frame reaches its final position.
If that does not happen, then simply try to change the structure design or ask the designers to do it.
Photo: Aeropuerto López Curbello - Punta del Este - Uruguay - Lifting a frame (with two cranes) - Nave Mayor.
These 52 m long frames are supported by those "V" that pivot in the concrete columns. But originally these "V" - (that are pipes) were supposed to be welded to the frame while it was hanging from two cranes. We decided that it was better to use bolts instead of welding, and to support the frame on the top of each pipe of the "V". Nevertheless the workers had to put the scaffold to put into place a few bolts prior to release the frame.
On the other hand, see how simple should be things when placing a large beam as in the next example:
Photo: Buenos Aires - Av. del Libertador bridge - Tren de la Costa. (L=40m x H=6m beam)
JOINTS: Almost always is better in any point of view to have the pieces welded in the shop and only to use bolts in the construction site. When you see the drawings before making the pieces at the shop, ask for modifications if you see joints to be welded during the erection: they should be bolted without arguing.