The Willamette locomotive was a geared locomotive of the Shay locomotive

Shay locomotive

The Shay locomotive was the most widely used geared steam locomotive. The locomotives were built to the patents of Ephraim Shay, who has been credited with the popularization of the concept of a geared steam locomotive...

 type, built by the Willamette Iron and Steel Works

Willamette Iron and Steel Works

Willamette Iron Works was a general foundry and machine business established in 1865 in Portland, Oregon, originally specializing in the manufacture of steamboat boilers and engines...

 of Portland, Oregon

Portland, Oregon

Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...

. Key patents on the Shay locomotive had expired, and it was now possible for other manufacturers to produce Shay "clones".

The Willamette locomotive was very similar to a Shay, but had many differences, as the company that made them intended on making an "improved Shay", even though the "Pacific Coast Shay", later made by Lima, took up many of the features on the Willamette. The differences were:

• All Willamettes were equipped with superheater
  Superheater
  A superheater is a device used to convert saturated steam or wet steam into dry steam used for power generation or processes. There are three types of superheaters namely: radiant, convection, and separately fired...
  
  s, while Shays usually were not
• The boiler
  Boiler
  A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
  
   parts were welded
  Welding
  Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material that cools to become a strong joint, with pressure sometimes...
  
   together, instead of being bolted together
• The Willamette locomotive used Walschaerts valve gear, while the Shay mainly used Stephenson valve gear
  Stephenson valve gear
  The Stephenson valve gear or Stephenson link or shifting link is a simple design of valve gear that was widely used throughout the world for all kinds of steam engine. It is named after Robert Stephenson but was actually invented by his employees....
  
  
• The rear cylinder on the Willamette was facing the same direction as the rest of the cylinders, while the two front cylinders on a Shay faced forward, with the rear cylinder facing backwards
• The back cylinder on a Willamette was moved forward of the cab, while in a Shay, the back cylinder was almost protruding into the cab
• The valve chests were turned outward
• The truck springs were inclined towards the bolster
• In a test done between a Shay and a Willamette, the Shay pulled 27 empty cars, while the Willamette pulled 29 empty cars, as well as using 40% less fuel

All but one Willamette burned oil, despite their working for logging companies, where wood would be abundant. Oil burners produced few sparks, however, and were less likely to ignite a forest than coal- or wood-fired locomotives. The only coal-fired Willamette worked for Anaconda Copper

Anaconda Copper

Anaconda Copper Mining Company was one of the largest trusts of the early 20th century. The Anaconda was purchased by Atlantic Richfield Company on January 12, 1977...

.

Six Willamettes survive; only one is operational at the Mt. Rainier Scenic Railroad

Mt. Rainier Scenic Railroad

The Mt. Rainier Scenic Railroad is a steam-powered heritage railroad operating in Washington State between Elbe and Mineral. The railroad travels on tracks that pass through thick forest just south of Mount Rainier. The depot, gift shop and ticket office are located in Elbe...

in Mineral, Washington.

External links

• Geared Steam Locomotive Works' Willamette pages