| Richard Trevithick's Fusible Plug | |
|---|---|
|
Origin |
Richard Trevithick |
|
Type |
Heat Sensitive Threaded Cylinder |
|
Effects |
Stabilizes dynamic temperature swings to within safe operation limits |
|
Downsides |
Releases copious amounts of steam that impede alteration |
|
Activation |
Exposure to pressure gradient |
|
Collected by |
Warehouse 12 |
|
Section |
|
|
Date of Collection |
June 8, 1896 |
| [Source] | |
Origin[]
Richard Trevithick (13 April 1771 – 22 April 1833) was a British inventor and mining engineer. The son of a mining captain, and born in the mining heartland of Cornwall, Trevithick was immersed in mining and engineering from an early age. He was an early pioneer of steam-powered road and rail transport, and his most significant contributions were the development of the first high-pressure steam engine and the first working railway steam locomotive. The world's first locomotive-hauled railway journey took place on 21 February 1804, when Trevithick's unnamed steam locomotive hauled a train along the tramway of the Penydarren Ironworks, in Merthyr Tydfil, Wales.
Turning his interests abroad Trevithick also worked as a mining consultant in Peru and later explored parts of Costa Rica. Throughout his professional career he went through many ups and downs and at one point faced financial ruin, also suffering from the strong rivalry of many mining and steam engineers of the day. During the prime of his career he was a well-known and highly respected figure in mining and engineering, but near the end of his life he fell out of the public eye.
In 1803, one of Trevithick's stationary pumping engines in use at Greenwich exploded, killing four men. Although Trevithick considered the explosion to be caused by a case of careless operation rather than design error, the incident was exploited relentlessly by James Watt and Matthew Boulton (competitors and promoters of the low-pressure engine) who highlighted the perceived risks of using high-pressure steam.
Trevithick's response was to incorporate two safety valves into future designs, only one of which could be adjusted by the operator. The adjustable valve comprised a disc covering a small hole at the top of the boiler above the water level in the steam chest. The force exerted by the steam pressure was equalized by an opposite force created by a weight attached to a pivoted lever. The position of the weight on the lever was adjustable thus allowing the operator to set the maximum steam pressure.
Trevithick also added a fusible plug of lead, positioned in the boiler just below the minimum safe water level. Under normal operation the water temperature could not exceed that of boiling water and kept the lead below its melting point. If the water ran low, it exposed the lead plug, and the cooling effect of the water was lost. The temperature would then rise sufficiently to melt the lead, releasing steam into the fire, reducing the boiler pressure and providing an audible alarm in sufficient time for the operator to damp the fire, and let the boiler cool before damage could occur. He also introduced the hydraulic testing of boilers, and the use of a mercury manometer to indicate the pressure.
Recoil Engine[]
In one of Trevithick's more unusual projects, he attempted to build a 'recoil engine' similar to the aeolipile described by Hero of Alexandria in about AD 50. Trevithick's engine comprised a boiler feeding a hollow axle to route the steam to a catherine wheel with two fine-bore steam jets on its circumference. The first wheel was 15 feet (4.6 m) in diameter and a later attempt was 24 feet (7.3 m) in diameter. To get any usable torque, steam had to issue from the nozzles at a very high velocity and in such large volume that it proved not to operate with adequate efficiency. Today this would be recognized as a reaction turbine.
Effects[]
Acts as a safety mechanism regulating extreme temperature conditions from becoming uncontrollable. Placing in a system that experiences heat changes (including state of matter transformation) makes the variation occur over a sustained period of time instead of instantaneous. For some instances this negates the entire purpose of the process such as explosions or welding, but allows others such as sustained growth and preservation to continue in the best possible circumstances.
Must be part of a closed-circuit system and cannot fully counter the larger environment, only regulate the part it’s attached with. To ensure the steady state is not disturbed, huge amounts of non-burning water vapor (steam in colder conditions) will push away any bystander by pressurization alone.