Keystone Hammer: Undone By Its Own Brute Force

摘要

The use of a hydraulic excavator or back-hoe-loader as a demolition machine with interchangeable tools is a relatively recent development in the 180-year history of mechanized excavating and construction equipment. But just as with so many other concepts of equipment design and application, it has roots in a machine from long ago. The Keystone Portable Steam Driller Co. was founded in 1882 at Beaver Falls, Penn., to produce a line of then-revolutionary self-propelled drills for applications such as farm and residential water supply, blast holes, and mineral prospecting. The firm prospered, and in 1912, it diversified into the manufacture of excavating machinery.