Anyang power hammers for blacksmith (from 9kg to 110kg) are self contained pneumatic power hammers. The design is based on the time proved designs of the old European hammers many which are still in use today. With a self contained power hammer, you require no external air supply or high pressure hoses.
The frames are cast iron, like the old Nazel, Beche, and Massey hammers. Cast iron is more expensive to manufacture compared to fabricated hammers but they are heavier, do not flex over time, and have a lifetime warranty on the frame.