Humphrys & Tennant
| Industry | Engineering |
|---|---|
| Founded | 1852 |
| Defunct | 1907 |
| Headquarters | Deptford, London |
|
Key people
|
Edward Humphrys |
| Products | Marine steam engines |
Humphrys, Tennant and Dykes (later named Humphrys, Tennant and Co.) was a British engineering company based in Deptford, London, England.
The company was founded by Edward Humphrys in 1852 and in 1882 the name was changed to Humphrys, Tennant and Co. of Deptford Pier, London. It specialised in building large marine steam engines and boilers, including those for the Navy's fast cruisers and iron-clad battleships. The 50 years of production started in the early days of screw-propellors (as opposed to paddle wheels) and spanned great changes in the available pressure from boilers and the resulting power of the engines, as well as in the construction and form of ships. Their main competitors were Maudslay, Sons and Field and John Penn and Sons. The works at Deptford Pier was closed in 1907.
One of the early records of a Humphrys, Tennant and Dykes steam engine was the conversion of the Russian ship of the line Konstantin to steam power between 1852 and 1854. The engine was rated at 450 nominal horsepower, and drove a single screw propellor. This early engine must have performed well, for when the Konstantin was retired in 1864 the engine was refurbished and installed in the Russian ironclad Ne Tron Menia, and its from the sea trials of this vessel in 1865 that we know the engine produced 1200 indicated horsepower (ihp). Fitted with new boilers in 1877, the sea trials showed the power improved to 1700 ihp.
The layout and type of the Konstantin engine was probably similar to the pair of direct-acting engines displayed at the 1862 International Exhibition, reputedly intended for HMS North Star. These were twin-cylinder non-compound horizontal engines with 64 inch cylinders and just 32 inches of stroke, allowing relatively short connecting rods. The crankshaft, of 13.5 inches diameter, was supported in 3 main bearings, each 25 inches long, on a single cast bedplate. Condenser air pumps were provided on the opposite side from the cylinders. Although rated as 400 nominal horsepower, with 24 psi steam (reflecting the very low marine boiler pressures typical at that time) the engine had shown 1834 ihp.
...
Wikipedia