Daniel Chapman Stillson Daniel Chapman Stillson Daniel Chapman Stillson (March 25, 1826 - August 23, 1899) was an American inventor. He invented the modern adjustable pipe wrench. He was born March 25, 1826 in Durham, New Hampshire. He was the son of William Stillson and Nancy Chapman. He married Ellen Raynes Davis on April 18, 1855. He was a machinist during the American Civil War and served on David Glasgow Farraguts first voyage as a vice admiral. At the end of the Civil War, Stillson returned to Charlestown, Massachusetts, and eventually he moved to Somerville, Massachusetts. He then worked as a machinist at
Tool steel their high chromium content, certain D-type tool steels are often considered stainless or semi-stainless, however their corrosion resistance is very limited due to the precipitation of the majority of their chromium and carbon constituents as carbides. ISO 1.2767, also known as DIN X 45 NiCrMo 4, AISI 6F7, and BS EN 20 B, is an air-hardening tool steel with a primary alloying element of nickel. It possesses good toughness, stable grains, and is highly polishable. It is primarily used for dies in plastic injection molding application that involve high stresses. Other applications include blanking dies, forging dies, and industrial blades.