Acetylene, the Principles of Its Generation and Use Part 27

[Ill.u.s.tration: FIG. 45.--"BON-ACCORD" GENERATOR.]

_Maker_: FREDK. BRABY AND CO., LTD., ASHTON GATE WORKS, BRISTOL; AND 352-364 EUSTON ROAD, LONDON.

_Type:_ (I) Automatic; carbide-to-water.

The "A" type of generator made by this firm comprises an equalising bell gasholder, round the bell of which are arranged a series of buckets which are charged with carbide. Those buckets are discharged in turn as the bell falls from time to time through a mechanism operated by a weight suspended from a wire cord on a revolving spindle. The carbide is discharged on to a different spot in the generating tank from each bucket. There is a c.o.c.k for the periodical removal of sludge. Gas pa.s.ses through a purifier charged with puratylene to the service-pipe. The disposition of the parts of the plant and the operating mechanism arc shown in the accompanying figure, which represents the generating apparatus partly in elevation and partly in section. The carbide buckets (1) are loosely hooked on the flat ring (2) bolted to the gasholder tank (3). The buckets discharge through the annular water-s.p.a.ce (4) between the tank and the generator (5). The rollers (6), fitted on the generator, support a ring (7) carrying radial pins (8) projecting outwards, one pin for each bucket. The ring can travel round on the rollers. Superposed on the ring is a tray (9) closed at the bottom except for an aperture beneath the throat (11), on which is mounted an inclined striker (12), which strikes the projecting tongues (1_a_) of the lids of the buckets in turn. There is fixed to the sides of the generator a funnel (13) with open bottom (13_a_) to direct the carbide, on to the rocking grid (14) which is farther below the funnel than appears from the figure. Gas pa.s.sing up behind the funnel escapes through a duct (15) to the gasholder. The ring (7) is rotated through the action of the weight (16) suspended by the chain or rope (17) which pa.s.ses round the shaft (18), which is supported by the bracket (19) and has a handle for winding up. An escapement, with upper limb (20_a_) and lower limb (20_b_), is pivotally centred at (21) in the bracket (19) and normally restrains the turning of the shaft by the weight. There is a fixed spindle (24) supported on the bracket (23)--which is fixed to the tank or one of the guide-rods--having centred on it a curved bar or quadrant (25) running loose on the spindle (24) and having a crank arm (26) to which is connected one end of a rod (27) which, at the other end, is connected to the arm (28) of the escapement. The quadrant bears at both extremities against the flat bar (29) when the bell (22) is sufficiently raised. The bar (29) extends above the bell and carries an arm (30) on which is a finger (30_a_). There is fixed on the shaft (18) a wheel (31), with diagonal divisions or ways extending from side to side of its rim, and stop-pins (32) on one side at each division. A clutch prevents the rotation of the wheel during winding up.

[Ill.u.s.tration: FIG. 46.--THE "A" GENERATOR OF FRED K. BRABY AND CO., LTD.]

(2) Automatic; water-to-carbide; contact, superposed trays.

The type "B" generator made by this firm comprises an equalising bell gasholder, a crescent-shaped feed water-tank placed on one side of the gasholder, and mechanism for controlling a tap on the pipe by which the feed water pa.s.ses to a washer whence it overflows through a seal into a horizontal generating chamber containing cells packed with carbide. The mechanism controlling the water feed embodies the curved bar (25), connecting-rod (27) and flat guide-bar (29) as used for controlling the carbide feed in the "A" type of generator (Fig. 46). When the bell descends water is fed into the washer, and the water-level of the seal is thus automatically maintained. The gas evolved pa.s.ses through a pipe, connecting the seal on the top of the generating chamber with the washer, into the gasholder. Plants of large size have two generating chambers with connexions to a single washer.

_Maker:_ THE DARGUE ACETYLENE GAS CO., 57 GREY STREET, NEWCASTLE-ON- TYNE.

_Type:_ Automatic; water-to-carbide; "drawer."

The "Dargue" acetylene generator made by this firm comprises an equalising bell gasholder _B_ floating in a water-tank _A_, which is deeper than is necessary to submerge the bell of the gasholder.

In the lower part of this tank are placed two or more horizontal generating chambers which receive carbide-containing trays divided by part.i.tions into a number of compartments which are half filled with carbide. Water is supplied from the gasholder tank through the tap _E_ and pipe _F_ to the generating chambers in turn. It rises in the latter and floods the first compartment containing carbide before gaining access to the second, and so on throughout the series of compartments. As soon as the carbide in the first generating chamber is exhausted, the water overflows from it through the pipe with by-pa.s.s tap _J_ to the second generating chamber. The taps _G_ and _H_ serve to disconnect one of the generating chambers from the water-supply during recharging or while another chamber is in action. The gas evolved pa.s.ses from each generating chamber through a pipe _L_, terminating in the dip-pipe _M_, which is provided with a baffle-plate having very small perforations by which the stream of gas is broken up, thereby subjecting it to thorough washing by the upper layers of water in the gasholder tank. The washed gas, which thus enters the gasholder, pa.s.ses from it through the pipe _N_ with main c.o.c.k _R_ to the service- pipes. The water-supply to the generator is controlled through the tap _E_, which is operated by a chain connected to an arm attached to the bell of the gasholder.

The water in the gasholder tank is accordingly made to serve for the supply of the generating chambers, for the washing of the gas, and as a jacket to the generating chambers. The heat evolved by the decomposition of the carbide in the latter creates a circulation of the water, ensuring thereby thorough mixing of the fresh water, which is added from time to time to replace that removed for the decomposition of the carbide, with the water already in the tank. Thus the impurities acquired by the water from the washing of the gas do not acc.u.mulate in it to such an extent as to render it necessary to run off the whole of the water and refill, except at long intervals. A purifier, ordinarily charged with puratylene, is inserted in many cases after the main c.o.c.k _R_. The same firm makes an automatic generator on somewhat similar lines, specially designed for use in autogenous welding, the smaller sizes of which are readily portable.

[Ill.u.s.tration: FIG. 47.--"DARGUE" GENERATOR.]

_Maker_: J. AND J. DRUMMOND, 162 MARKET STREET, ABERDEEN.

_Type_: Automatic; water-to-carbide; contact.

The generating plant made by this firm comprises two or more generating vessels _B_ in which carbide is contained in removable cases perforated at different levels. Water is supplied to these generating vessels, entering them at the bottom, from an elevated tank _A_ through a pipe _C_, in which is a tap _F_ connected by a lever and chain _L_ with the bell _G_ of the equalising gasholder _H_, into which the evolved gas pa.s.ses. The lever of the tap _F_ is counter-weighted so that when the bell _G_ descends the tap is opened, and when the bell rises the tap is closed. The gas pa.s.ses from the generating chambers _B_ through the pipe _D_ to the washer-cooler _E_ and thence to the gasholder. From the latter it pa.s.ses through the dry purifier _J_ to the service-pipe. The gasholder bell is sealed in oil contained in an annular tank instead of in the usual single-walled tank containing water. The purifying material ordinarily supplied is puratylene. The apparatus is also made to a large extent in a compact form specially for use on board ships.

[Ill.u.s.tration: FIG. 48.--J. AND J. DRUMMOND'S GENERATING PLANT.]

_Agents_: FITTINGS, LTD., 112 VICTORIA STREET, S.W.

_Type_: Automatic; carbide-to-water.

The "Westminster" generator supplied by this firm is the "Davis"

generator described in the section of the United States. The rights for the sale of this generator in Great Britain are held by this firm.

_Maker_: LOCKERBIE AND WILKINSON, TIPTON, STAFFS.

_Type_: (1) Automatic; water-to-carbide; contact, superposed trays.

The "Thorscar" generator of this firm comprises an equalising gasholder, the gas-s.p.a.ce of the bell _B_ of which is reduced by conical upper walls. When the bell descends and this lining enters the water in the tank _A_ the displacement of water is increased and its level raised until it comes above the mouths of the pipes _E_, through which a portion then flows to the generators _D_. The evolution of the gas in the latter causes the bell to rise and the conical lining to be lifted out of the water, the level of which thereupon falls below the mouths of the pipes _E_ in consequence of the reduced displacement of the bell. The supply of water to the generators is thus cut off until the bell again falls and the level of the water in the tank is raised above the mouths of the pipes _E_. The generating chambers _D_ are provided with movable cages _F_ in which the carbide is arranged on trays. The gas evolved travels through a scrubbing-box _G_ containing charcoal, and the pipe _J_ with drainage-pipe _P_ to the water-seal or washer _K_ inside the holder, into which it then pa.s.ses. The outlet-pipe for gas from the holder leads through the condensing coil _L_ immersed in the water in the tank to the condensed water-trap _N_, and thence by the tap _Q_ to the supply-pipe. The generating chambers are water-jacketed and provided with gauge-gla.s.ses _H_ to indicate when recharging is necessary, and also with sludge-c.o.c.ks _M_. The object of the displacement cone in the upper part of the bell is to obtain automatic feed of water to the carbide without the use of c.o.c.ks or movable parts. There is a funnel- shaped indicator in front of the tank for regulating the height of water to a fixed level, and also an independent purifier, the purifying material or which is supplied under the proprietary name of "Thorlite."

[Ill.u.s.tration: FIG. 49.--"THORSCAR" GENERATOR.]

(2) Non-automatic; water-to-carbide; "drawer."

This generating plant, the "Thorlite," comprises a water-tank _A_ from which water is admitted to the drawer generating chambers _B_, one of which may be recharged while the other is in operation. The gas evolved pa.s.ses through a seal _C_ to the gasholder _D_, whence it issues as required for use through the purifier _E_ to the supply-pipe. For the larger sixes a vertical generating chamber is used.

The purifier and purifying material are the same as for the automatic plant of the same firm.

[Ill.u.s.tration: FIG. 50.--"THORLITE" GENERATING PLANT.]

_Maker_: THE MANCHESTER ACETYLENE GAS CO., LTD., ACRE WORKS, CLAYTON, MANCHESTER.

_Type_: Automatic; water-to-carbide; "drawer."

The plant made by this firm comprises an equalising gasholder _A_ from the tank of which water is supplied to generating cylinders _B_ placed at the side of the tank, the number of which varies with the capacity of the plant. The cylinders receive tray carbide-containers divided into compartments perforated at different levels so that they are flooded in turn by the inflowing water. A weight _C_ carried by a chain _D_ from one end of a lever _E_ pivoted to the framing of the gasholder is supported by the bell of the gasholder when the latter rises; but when the holder falls the weight _C_, coming upon the lever _E_, raises the rod _F_, which thereupon opens the valve _G_, which then allows water to flow from the gasholder tank through the pipe _H_ to one of the generating cylinders. When the carbide in the first cylinder is exhausted, the water pa.s.ses on to a second. One generating cylinder may be recharged while another is in action. The rising of the holder, due to the evolved gas, causes the bell to support the weight _C_ and thus closes the water supply-valve _G_. The gas evolved pa.s.ses through vertical condensers _J_ into washing- boxes _K_, which are placed within the tank. The gas issues from the washing-boxes into the gasholder bell, whence it is withdrawn through the pipe _L_ which leads to the purifier. Puratylene is the purifying material ordinarily supplied by this firm.

[Ill.u.s.tration: FIG. 51.--GENERATING PLANT OF THE MANCHESTER ACETYLENE GAS CO., LTD.]

_Maker:_ R,. J. MOSS AND SONS, 98 SNOW HILL, BIRMINGHAM.

_Type:_ (1) Automatic; water-to-carbide; superposed trays.

The "Moss" generator, "Type A," made by this firm comprises an equalising gasholder, four, three, or two generating chambers, and an intermediate water-controlling chamber. Each generating chamber consists of a frame in which are arranged about a central tube trays half filled with carbide, having water inlet-holes at several different levels, and each divided into two compartments. Over this frame is put a bell-shaped cover or cap, and the whole is placed in an outer tank or bucket, in the upper part of which is a water inlet-orifice. The water entering by this orifice pa.s.ses down the outside of the bell, forming a water-seal, and rises within the bell to the perforations in the carbide trays from the lowest upwards, and so reaches the carbide in successive layers until the whole has been exhausted. The gas evolved pa.s.ses through the central tube to a water- seal and condensing tank, through which it escapes to the controlling chamber, which consists of a small water displacement chamber, the gas outlet of which is connected to the equalising gasholder. The bell of the equalising gasholder is weighted or balanced so that when it rises to a certain point the pressure is increased to a slight extent and consequently the level of the water in the displacement controlling chamber is lowered. In this chamber is a pipe perforated at about the water-level, so that when the level is lowered through the increased pressure thrown by the rising gasholder the water is below the perforations and cannot enter the pipe. The pipe leads to the water inlet-orifices of the generating tanks and when the equalising gasholder falls, and so reduces the pressure within the controlling chamber, the water in the latter rises and flows through the pipe to the generating tanks. The water supplied to the carbide is thus under the dual control of the controlling chamber and of the differential pressure within the generating tank. The four generators are coupled so that they come into action in succession automatically, and their order of operation is naturally reversed after each recharging. An air-c.o.c.k is provided in the crown of the bell of each generator and, in case there should be need of examination when charged, c.o.c.ks are provided in other parts of the apparatus for withdrawing water. There is a sludge-c.o.c.k on each generator. The gas pa.s.ses from the equalising gasholder through a purifier, for which the material ordinarily supplied is puratylene.

[Ill.u.s.tration: FIG. 52.--"MOSS TYPE A" GENERATOR.]

The "Moss Type B" generator is smaller and more compact than "Type A." It has ordinarily only two generating chambers, and the displacement water controlling chamber is replaced by a bell governor, the bell of which is balanced through a lever and chains by a weight suspended over the bell of the equalising gasholder, which on rising supports this counter-weight and so allows the governor bell to fall, thereby cutting off the flow of water to the generating chambers.

[Ill.u.s.tration: FIG 53.--"MOSS TYPE B" GENERATOR.]

The "Moss Type C" generator is smaller than either "Type A" or "B," and contains only one generating chamber, which is suspended in a pocket in the crown of the equalising gasholder. Water enters through a hole near the top of the bucket of the generating chamber, when it descends with the holder through the withdrawal of gas from the latter.

[Ill.u.s.tration: FIG 54.--"MOSS TYPE C" GENERATOR.]

(2) Semi-automatic; water-to-carbide; superposed trays.

The "Moss Semi-Non-Auto" generating plant resembles the automatic plant described above, but a storage gasholder capable of holding the gas evolved from one charging of the whole of the generating chambers is provided in place of the equalising gasholder, and the generation of gas proceeds continuously at a slow rate.

The original form of the "Acetylite" generator (_vide infra_) adapted for lantern use is also obtainable of R. J. Moss and Sons.

_Maker:_ WM. MOYES AND SONS, 115 BOTHWELL STREET, GLASGOW.

_Type:_ Automatic; carbide-to-water.

The "Acetylite" generator made by this firm consists of an equalising gasholder and one or more generating tanks placed alongside it. On the top of each generating tank is mounted a chamber, with conical base, charged with granulated carbide 1/8 to 1/2 inch in size. There is an opening at the bottom of the conical base through which pa.s.ses a rod with conical head, which, when the rod is lowered, closes the opening. The rod is raised and lowered through levers by the rise and fall of the bell of the equalising gasholder, which, when it has risen above a certain point, supports a counter-weight, the pull of which on the lever keeps the conical feed-valve open. The gas evolved in the generating tanks pa.s.ses through a condensing chamber situated at the base of the tank into the equalising gasholder and so automatically controls the feed of carbide and the evolution of gas according to the rate of withdrawal of the gas from the holder to the service-pipes. The water in the gasholder tank acts as a scrubbing medium to the gas. The generating tanks are provided with sludge-c.o.c.ks and a tap for drawing off condensed water. The gas pa.s.ses from the equalising gasholder, through a purifier and dryer charged with heratol or other purifying material to the service-pipes.

The original form of the "Acetylite" generator is shown in elevation and vertical section in Fig. 55. Wm. Moyes and Sons now make it also with a detached equalising gasholder connected with the generator by a pipe in which is inserted a lever c.o.c.k actuated automatically through a lever and cords by a weight above the bell of the gasholder. Some other changes have been made with a view to securing constancy of action over long periods and uniformity of pressure. In this form the apparatus is also made provided with a clock-work mechanism for the supply of lighthouses, in which the light is flashed on periodically. The flasher is operated through a pilot jet, which serves to ignite the gas at the burners when the supply is turned on to them at the prescribed intervals by the clock- work mechanism.

[Ill.u.s.tration: FIG. 55.--"ACETYLITE" GENERATOR.]

_Maker_: THE PHoS CO., 205 AND 207 b.a.l.l.s POND ROAD, LONDON, N.

_Type_: Non-automatic; water-to-carbide; drip.

The type "E" generator made by this firm consists of a generating chamber placed below a water chamber having an opening with cap _E_ for refilling. The generating chamber in closed by a door _B_, with rubber washer _C_, held in position by the rod _A_, the ends of which pa.s.s into slots, and the screw _A'_. The movable carbide chamber _D_ has its upper perforated part half filled with carbide, which is pressed upwards by a spring _D'_. The carbide chamber when filled is placed in the generating chamber, which is closed, and the lever _F_ of one of the taps _F'_ is turned from "off" to "on,"

whereupon water drips from the tank on to the carbide. The evolution of gas is stopped by reversing the lever of the tap. The second tap is provided for use when the evolution of gas, through the water-supply from the first tap, has been stopped and it is desired to start the apparatus without waiting for water from the first tap to soak through a layer of spent carbide. The two taps are not intended for concurrent use. The evolved gas pa.s.ses through a purifier containing any suitable purifying material to the pipes leading to the burners.