Nortonthorpe Mills - Whitehead governor

Image: © Chris Allen Taken: 7 Oct 2006

This is on the Pollit and Wigzell tandem compound mill engine and closely regulates the engine's speed by controlling the amount of steam entering the cylinders by changing the high pressure cut-off - Image Close speed regulation was important in the textile trades and there were various governors that claimed to be capable of holding the speed consistently close to the design speed even though the load was varying. This is a clever trick as a simple governor has a specific speed for each position of the balls and hence for each cut-off position. Designs such as the Collamore attachment, the Lumb's governor with Wilby's regulator and the Whitehead governor (to name some) effectively circumvented this and the engine's speed was more or less constant over a wide load range. The Whitehead was used by Pollit and Wigzell latterly although many customers specified the Lumb's or had it retrofitted. The Whitehead looks deceptively simple but contained a second internal spring and dashpot arrangement that compensated for changes in load and speed to bring the engine back to design speed.

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