Part 1 (1/2)
Steam, Its Generation and Use
by Babcock & Wilcox Co
THE EARLY HISTORY OF THE GENERATION AND USE OF STEAM
While the tie and use of the expansive force of the vapor of water is unknown, records show that such knowledge existed earlier than 150 B C In a treatise of about that time entitled ”Pneu devices of his predecessors and contemporaries but also an invention of his ohich utilized the expansive force of stea water above its natural level He clearly describes three ht be used directly as aa weight by its expansive power and producing a rotary motion by its reaction on the atine”, is described as a hollow sphere supported over a caldron or boiler by two trunnions, one of which was hollow, and connected the interior of the sphere with the steam space of the caldron Two pipes, open at the ends and bent at right angles, were inserted at opposite poles of the sphere, for a connection between the caldron and the atenerated passed through the hollow trunnion to the sphere and thence into the ath the two pipes By the reaction incidental to its escape through these pipes, the sphere was caused to rotate and here is the priestions as to application of any of the devices he describes to a useful purpose From the time of Hero until the late sixteenth and early seventeenth centuries, there is no record of progress, though evidence is found that such devices as were described by Hero were soan or the turning of a skillet
Mathesius, the German author, in 1571; Besson, a philosopher and mathematician at Orleans; Ramelli, in 1588; Battista Delia Porta, a Neapolitan matheineer and architect, in 1615; and Branca, an Italian architect, in 1629, all published treatises bearing on the subject of the generation of steam
To the next contributor, Edward Somerset, second Marquis of Worcester, is apparently due the credit of proposing, if not of ine In the ”Century of Scantlings and Inventions”, published in London in 1663, he describes devices showing that he had init from two receivers by direct stea piston actuating one end of a lever, the other operating a pus are extant so that it is difficult to say whether there were any distinctly novel features to his devices aside from the double action While there is no direct authentic record that any of the devices he described were actually constructed, it is claiine containing pistons
In 1675, Sir Sa Charles II, for a demonstration of ”a certain powerful h there appears to be no record of the design of this machine, the mathematical dictionary, published in 1822, credits Moreland with the first account of a steaine, on which subject he wrote a treatise that is still preserved in the British Museum
[Illustration: 397 Horse-power Babcock & Wilcox Boiler in Course of Erection at the Plant of the Crocker Wheeler Co, Aenious Frenchtheer from explosion, added a contrivance which is the first safety valve on record
The steaine first became commercially successful with Thomas Savery In 1699, Savery exhibited before the Royal Society of England (Sir Isaac Neas President at the tiine which consisted of two copper receivers alternately connected by a three-way hand-operated valve, with a boiler and a source of water supply When the water in one receiver had been driven out by the stea a vacuuain while the water in the other reservoir was being forced out A number of machines were built on this principle and placed in actual use as mine pumps
The serious difficulty encountered in the use of Savery's engine was the fact that the height to which it could lift water was limited by the pressure the boiler and vessels could bear Before Savery's engine was entirely displaced by its successor, Newcouliers, who applied the Papin safety valve to the boiler and substituted condensation by a jet within the vessel for Savery's surface condensation
In 1690, Papin suggested that the condensation of steam should be employed to make a vacuum beneath a cylinder which had previously been raised by the expansion of steaine and his plan took practical shape in Newcoine was unworkable owing to the fact that he used the same vessel for both boiler and cylinder A small quantity of water was placed in the bottom of the vessel and heat was applied When steam formed and raised the piston, the heat ithdrawn and the piston did work on its down stroke under pressure of the atine, Papin developed an iine of 1705 consisted of a displacem or piston on top of the water kept the steam and water from direct contact The water delivered by the doard movement of the piston under pressure, to a closed tank, flowed in a continuous streaainst the vanes of a water wheel When the steam in the displacement chah a valve instead of being condensed The engine was, in fact, a non-condensing, single action steam pump with the steaine was a heater placed in the diaphragm This was athe stea expansion
This devicethe various inventions attributed to Papin was a boiler with an internal fire box, the earliest record of such construction
While Papin had neglected his earlier suggestion of a steaine to work on Savery's ideas, Thomas Newcomen, with his assistant, John Cawley, put into practical forestion of 1690 Steam admitted from the boiler to a cylinder raised a piston by its expansion, assisted by a counter-weight on the other end of a beam actuated by the piston The steam valve was then shut and the steam condensed by a jet of cold water The piston was then forced doard by atmospheric pressure and did work on the puh an escapeine used stea pressure but little, if any, above that of the atmosphere
[Illustration: Two Units of 8128 Horse Power of Babcock & Wilcox Boilers and Superheaters at the Fisk Street Station of the Co Installed in this Station
The Commonwealth Edison Co Operates in its Various Stations a Total of 86,000 Horse Power of Babcock & Wilcox Boilers, all Fitted with Babcock & Wilcox Superheaters and Equipped with Babcock & Wilcox Chain Grate Stokers]
In 1711, this engine was introduced into inally automatic or whether dependent upon the hand operation of the valves is a question of doubt The story commonly believed is that a boy, Humphrey Potter, in 1713, whose duty it was to open and shut such valves of an engine he attended, by suitable cords and catches attached to the beaine to automatically manipulate these valves This device was sihton, who suspended fro-tree, which actuated the valve by tappets By 1725, this engine was in coed but little for a ine, froine, Newcomen's was a distinct advance, in that the pressure in the pumps was in no manner dependent upon the steaine, the losses fro of the steaht have been modified to serve many purposes, its use see of water
The rivalry between Savery and Papin appears to have sti Dr John Allen, in 1730, called attention to the fact that owing to the short length of ti surfaces of the boiler, nearly half of the heat of the fire was lost With a view to overco this loss at least partially, he used an internal furnace with a sh the water in the fore of the gases ht not act as a damper on the fire, Dr Allen recoish vapor through the flue This is probably the first suggested use of forced draft In for an estimate of the quantity of fuel lost up the stack, Dr Allen probably made the first boiler test
Toward the end of the period of use of Newcoine, John Se engines of this type, greatly in in its mechanical details
[Illustration: Erie County Electric Co, Erie, Pa, Operating 3082 Horse Power of Babcock & Wilcox Boilers and Superheaters, Equipped with Babcock & Wilcox Chain Grate Stokers]
The in of Smeaton, Newcoreat engineer, Jaow In 1763, while repairing a reat waste of steaave rise
His re of the cylinder as hot as the entering steam and with this in view he added a vessel separate from the cylinder, into which the steam should pass from the cylinder and be there condensed either by the application of cold water outside or by a jet from within To preserve a vacuum in his condenser, he added an air pump which should serve to reht in with the injection water or due to leakage As the cylinder no longer acted as a condenser, he couldit with non-conducting material and, in particular, by the use of a steam jacket Further and with the same object in view, he covered the top of the cylinder and introduced steam above the piston to do the work previously accomplished by atmospheric pressure After several trials with an experimental apparatus based on these ideas, Watt patented his improvements in 1769 Aside from their historical importance, Watt's improvements, as described in his specification, are to this day a stateuide the scientific developine His words are: