Watt Steam Engines

James Watt

The engine of Newcomen was very wasteful of coal even if there have been many improvements to the engine. James Watt was a man who wanted to know the exactness of things. He studied the Newcomen engine very precise and was astonished on how there was a need of water to be injected to cool down the steam. He recognized that there was a relevant loss of power. Watt made many studies concerning steam pressure, which he used for his great cognition. He recognized that it was useles to cool down the same vessel and heat it again. In his patent, he formulated among other things two principles:

1.Thermal insulation
The vessel, which worked by means of steam, had to be as hot as the steam itself.

2.Separate condenser
The vessel where the steam is condensed has to be separated from the cylinder and it has to be as cold as the outside temperature. Watt called it the "condenser."

Watt united these two principles in his first steam engine.

Watt's First Steam Engine (1776)

Watts first steam engine was (like the Newcomen-Engine) working at low pressure. The power could of course be enlarged by increasing the steam pressure, but it could also simply be enlarged by building greater cylinders. The advantage was that there was no need to work with high pressure. Therefore, not many detonations of the boiler ocurred.

One of the main problems Watt had was not technical related but of financial crisis. So the partnership with Matthew Boulton was very good for him; it made the base of all the inventions James Watt made.


Natural Expansion of The Steam

Watt discovered that there was no need to conduct steam during all the time the piston moved up. The natural expansion of steam can be used. The quantity of steam can be reduced to a fourth. Therefore, the piston did not press with the same force all the time, but Watt found out that this problem could be fixed with a fly-wheel.
Watt's second patent described among other things how the natural expansion of steam could be used. He described six ways of providing a regular running of the engine. He also described the double-acting engine in this patent and all the technical details which are necessary to provide a regular running of it. After a while there was also the idea of converting the up and down-movement of the piston into a rotating movement. Unfortunately, there was a patent of a man on this convertion. Watt and Boulton could go round it by inventing some new drivings. The invented i.e. the so called sun-driving.

James Watt also invented some new technical features of regulating the running of the engine. One of the most important inventions was the fly ball governor, which automatically regulated the conveying of steam.