Upon being knighted in 1716 he changed his name from Polhammar to Polhem. He founded several schools and is considered to be the father of Swedish engineering. He was a contemporary and close friend of Emanuel Swedenborg.
After successful repairs of the medieval (1500s) clockwork by Petrus Astronomus at Uppsala Cathedral, he caught the attention of King Charles XI of Sweden who asked him to look into machinery for mining, following a disaster in Falun, where the entire big mine had collapsed. Polhem constructed a winchlike device for lifting and transporting ore from the mine in Falun, which was also built in a stripped-down version. The king was so impressed by this device that he gave Polhem a lifelong pension for his services to the state.
His biggest achievement was an entire large-scale industry, built in Stjärnsund and blessed by the new King Charles XII of Sweden. This industry was run on water power alone, featured more automation than any other industry, and would produce all kinds of goods. However, following a fire in 1734 most of the industry was destroyed, and only clock manufacturing remained. The clocks produced in Stjärnsund were of high quality and cheap, as they were mass-produced. Another product from Stjärnsund was padlocks. Polhem was the principal inventor of the modern padlock.
He shares his portrait with Charles XI on the Swedish 500 Krona bank notes, with the king on the front side and Polhem on the reverse.
See also: List of Swedish scientists