The Vulcan 30C was the differential-acting counterpart to the single-acting #2 hammer. Specifications are below.
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The general arrangements are interesting not just for the 30C but to explain features and variants in the Vulcan product line.
The bar head type 30C shows the way the cushion, driving accessory and top plate mate to the hammer.
The bar type head was easy to connect with the leaders, but did not allow for the mechanical advantage of the sheave. It fell out of favour with the onshore hammers, but came back (with its variant, the suspension head) to be standard with the offshore hammers.
The sheave type head, standard with Vulcan onshore hammers. Frequently, however, contractors will remove the sheave and lift the hammer with the sheave pin, negating the mechanical advantage of the sheave.
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