Crane Boom Hinge Pin Dimensions

it'll depend on the load, then pick a diameter (and material) that suits.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

I already know the load itll be subjected to and a suitable material, but how should I go on to choose the diameter? And once I have it, what should I do then to get its length and ensure these will be able to withstand the load?

there should be a table somewhere (catalogues ? specs ??) where bolt strengths are given (for different sizes and materials).

try googling "types of bolts" and "strength of bolts".

be aware of the difference between single shear and double shear (which I think you'll have).

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

Do you know the load on the pin or the load on the crane?