How about connecting bolts of overhead launching girder?

As all parts of overhead launching girder are produced, they need to be connected together by connecting bolts as below:

CONNECTING PARTS OF MAIN GIRDER

Steel pins for connecting main girder, material: 40Cr

Strike a pin into the hole at connecting parts, then add split pin at end to avoid it sliding out. Usually it only takes several minutes to strike a pin, quite safe, reliable, convenient and save time.

High strength bolts for connecting other parts, material: 8.8 grade

High strength bolts are made up of bolts, nuts and steel washers, they connect all parts except main girder.