Coupling between crane itself and the Stokes weight-relieving bogie. The weight of the crane in transit was partially transferred to the bogie via the ball and socket at the top and the arm at the bottom.
<p>At bottom left can be seen the track clip for attaching the crane to the rails during lifts.
</p>
Cowans Sheldon 50 ton breakdown crane MP4 (1930)
RichardAsh1981
CC BY-SA 2.0
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