In the 16th and 17th centuries, coal was exploited in large quantities as an energy source. As coal mines increase and mines are opened deeper and deeper, removing accumulated water in mines has become a key issue in coal production. There is an urgent need to find new power machines to solve economic and production needs. Papen and Newcomen successively designed steam power engines, but due to explosive hazards, low efficiency and other reasons, they could not meet the needs. In order for the steam engine to become a power machine with huge industrial benefits, major structural improvements must be made. This work was finally realized in the UK by Watt, a university instrument repairman.
James Watt was born in a carpenter family in Scotland in 1736. He suffered from poverty and disease since childhood. His education was received at home and in his father's workshop. In 1756, he worked as a mechanic at the University of Glasgow. In 1763, he was ordered to repair a Newcomen steam engine at the university. He was able to carefully study the structure of the Newcomen engine and found that its excessive heat loss was due to the fact that the cylinder and piston had to be cooled every time it worked. In 1765 he finally came up with the idea of ??adding a condenser after the cylinder. In 1769, he built the first "single-action steam engine" and obtained a patent for the condenser. In 1782, he further designed a two-way cylinder, and in 1784 he built a "two-stroke steam engine" and added a flywheel and a centrifugal governor to turn one-way motion into rotational motion.
The main feature of the Watt steam engine is to change the work done by atmospheric pressure to the work done by steam directly pushing the piston, adding a condenser and improving efficiency. This took a decisive step in the history of the development of the steam engine, becoming the universal "prime mover" that can be used for all power machinery. By 1790, the Watt engine had almost completely replaced the old Newcomen engine. The textile, mining and metallurgical industries developed rapidly under the leadership of the Watt engine, and the era came when the steam engine changed the entire world.
Watt’s entire life was dedicated to the development of steam engines. Engels regarded the steam engine as the first truly international invention, which is the best evaluation of his contribution. In order to commemorate him, the British specially built a bronze statue of him at his residence.