Design Principles
When on the move, a steam locomotive requires steam to enter the piston at a controlled rate. This entails controlling the admission and exhaustion of steam to and from the cylinders. Steam enters and leaves the valve through a steam port, usually at the middle position of the piston valve. Where the valve is in contact with the steam ports, a consideration of the "lap" and "lead" is required.
Read more about this topic: Piston Valve (steam Engine)
Famous quotes containing the words design and/or principles:
“Westerners inherit
A design for living
Deeper into matter—
Not without due patter
Of a great misgiving.”
—Robert Frost (1874–1963)
“All those who write either explicitly or by insinuation against the dignity, freedom, and immortality of the human soul, may so far forth be justly said to unhinge the principles of morality, and destroy the means of making men reasonably virtuous.”
—George Berkeley (1685–1753)