Crosshead

A crosshead is a mechanism used in most steam locomotives to eliminate sideways pressure on the piston.

Crossheads in a steam locomotive can be mounted either to one guide mounted above the crosshead or to two, one above and one below (called an alligator crosshead since it has two "jaws"). The former was preferred in many modern locomotives.

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  Crosshead and slide block

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  Detail crosshead of a steam locomotive

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  Cylindrical crosshead (New Catechism of the Steam Engine, 1904)

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  A Crosshead of the "slipper" or "shoe guide" form, as used on some stationary engines.

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  Crosshead of a French locomotive

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  Note the brass oil wells on top of the cross slide

External Links

• "Crosshead", Wikipedia
• "Allen Mogul Crosshead Question", Chaski.org
• "How Steam Engines Work", HowStuffWorks.com; Nice animation of piston, valve and crosshead action
• "Re-Babbitting the crosshead"