US1494224A - Valve for blast furnaces - Google Patents

Description

May as, 1924 1,494,224

W. DYRSSEN VALVE FOR BLAST FURNACES Filed Dec. l, 1921 2 Sheets-Sheet l o wvl-:mote Waldemar yrxen 22 Y May 13 i924.

W. DYRSSEN `VALVE FOR BLAST FURNACES INV ENTOR [Yy/"55m Wa/demar ATTRNEY natasha may ta, Esae.

t' tl DYRSSEN, 0F NEW YORK, N. Y.

vnnvn non. nmsrruacm.

Application tiled December l, 1921. Serial No. 519,107.

To all whom t may concern Be it known that l, WALDEMAR DYnssnN, a citizen of the United States, and resident of the city, county, and State of New York,

have invented certain new and useful lmprovements in Valves for Blast Furnaces, of which the following is a specification.

This invention relates to valves for ,cona

4 trolling the passage ofthe blast of air or gas from a hot blast stove to a blast furnace or vice versa. Valves used for-this purpose are subjected to extremely high temperatures andrit has formerly been necessary to provide means for water cooling such valves and also their valve seats.` In order to make the valves air-tight it has therefore been necessary to use parts'which were carefully machined` so that the valve would accurately contact with its seat. In order to revent the valve seat from becoming warpe or distorted it has alsoI been customary to make the same hollow to provide for a circulation of cooling water. This practice has been unsatisfactory because even when water cooled, the valve seats often warp which results in a leakage of hot air or gas past the valves which soon *burns them,v away and` makes necessary frequent renewals. This results in interfering with the continuous operation of the furnace and consequently reduces the output thereof. Water cooled valves and valve seats also tend to reduce the telnperature of the surrounding brickworkand consequently this reduces the temperature of the air passing through the conduits in said `brickwork The leakage of. cooling water is a disadvantageinherent to vvalves formerly constructed. Such leakage moistens the gas'or air and interferes with the proper operation of the blast furnace and increases the fuel consumption thereof.

One obiect of my invention is to overcome the disadvantages above enumerated and other objects will be apparent from the following description when read in connection with the accompanying drawings in which- Fig. 1. is a vertical section .showing my im- 'proved valve in closed posltlon;

Fig. 2 is a similar view showing the valve in open posltion; L

The valve as a whole consists of several /parts and includes a substantially cylindrical bell 2 which is adapted to enter an annular trough 4 which contains a bod of suitable uid 6, such as mercury, whlch makes l a fluid seal.

vwith anV air-tight bushing A gage 7 is connectedv to the trough 4 to indicate the height of the mercurytherein. Mercury is a convenient medium to use for this seal as it will readil withstand the heat and the pressures whic 60 exist in installations of this kind.; For example7 'a seal or column of mercury 40 inches high will withstand a pressure of 19 pounds per s uare inch.

Located be ow the bell 2 of the valve is a 65 cover 8 comprising a shell 10 provided with a suitablerefractor lining 12 such as firebrick. The top vor ome 3 of thebell 2 supports anotherv part of the valve com rising a hollow cylindrical wall 14 which 1s pro- 70 vided with securing angles 16 at the base and an angular rim 18 at 'the top which are connected vto one another by suitable up rights 17. The cylindrical wall 14 is of substantially the same diameter as'the bell 2 75 and is arranged to be moved therewith. When the valve is in theA closed position shown in Fig-1, the cylindrical wall 14 cuts oil' communicationl between the pipe 20 which leads to the hot blast main flue 22 which is .connected to the hot blast stove.

rlhe valve is so constructed that pratically no heat is carried by radiation to the inetallic parts of itsstructure. position the valve is enclosed by a cylindrical hood 24having a head 26 which is providedv or gland 28 through vwhich yslides a tubular stem 30 which is connected by an annular fitting 32 90 to the'dome 3 of the bell. To the upper end of the stem 30 is secured a head 34 carrying studs 36 to which are fastened cables 38 which pass overlsheaves and are connected with suitable means, not shown, for lifting @5 and lowering the valve stem and associate parts. Located within the valve stern 30 is a second stem 40 which is connected at 42 to the casing 10 of the cover 8. This second stem 40 is with a collar 44 which is adapted to co-act with a shoulder 46, formed by the end of the valve stem 30, when the 'latter is lifted. Aswill be apparent from Fig. 1 the valve stem 30 must be lifted an appreciable dis- 105 tance before the shoulder 46 strikes the underside of the collar. This arrangement permits the bell member 2 of the valve to be lifted a greater distance than the cover member 8` In other words, when the stem 110 and the 80 In its opened provided -at its upper end side of the cover 8 and is deflected out through the pipe 20.

lt is to be noted that the portion of the cover 8 which is eX osed to the heated air is formed of fire-brick or other refractory material so that '1t is practically unaffected thereby. In valves formerly used the metallic mushroom valve head would occupy about the same position as the dome 3 of the bell 2 in Fig. 2. It is clear that a metallic valve of mushroom shape in such location would be subjected to the destructive action of the excessive heat from the air 2: coming from the hot blast stove, the temperature of such air blast beingl approximately 1400 degrees F. In former installations the air pocket above the pipe 2O interferes with the free passage of the heated air from the stovefto the hot blast main. To prevent the mushroom valves heretofore used from being ruined by the hot gases, it has been customary to water cool them and in practice water frequently leaks out and the moisture is carried to the blast furnace, and as before stated, interferes with its best operation and increases the consumption of fuel. Such water cooling also tends to cool the brickwork and consequently reduces the temperature of the air supplied to the furnace and hence absorbs part of the heat supplied by the stoves, thereby lowering their efficiency. @n the other hand my improved valve does not require water cooling means and hence the above objections are overcome. When the valve is in closed position, lFig. 1, air dowing from the pipe 2O cannot possibly escape by leakage to the hot blast stove through the due 22 because of the liquid seal formed by the bell 2 extending down into the body of mercury 6.

When the bell 2 is in the closed position, the wall 14 closes the opening at the end of the pipe and prevents the radiation of heat to the metallic parts of the valve. The small quantity of air or gas which escapes through the clearance space between the wall 14 and the inner surface 15 ofthe body of the valve into the space enclosed by the hood 24 will be cooled bythe eHect of the surrounding atmosphere. lf necessary or desirable the outer surface of the hood 24 and its dome 26 may be water cooled by means of a s ray emanating from a circular pipe 48 whic is connected to a supply pipe 50. A trough 52 is provided near the upper aeeaaae portion of the hood and fills up with water and overflows, thus permitting a thin film ofwater to trickle down the outer surface of the hood which is caught in another trough 54 formed near the bottom of said hood. The trough 54 is connected by a pipe 56 with an open water jacket 58 which sur rounds the portion of the valve adjacent to the liquid seal and an overflow pipe 60 is connected near the top of the water jacket and leads to a suitable discharge. The water connections described are not absolutely essential a-nd are illustrated merely to show that in handling gas or air of exceedingly high temperatures above that normally used in blast furnace practice that such water cooling means can be applied. Or if a fluid of a lower melting point than that of mercury be used for the seal, it may be desirable to provide the water cooling arrangement to prevent the boiling away of the fluid used for such seal.

rlhe valve stems and 40 are preferably air cooled by means of air introduced through a pipe 62 connected to a tubular extension 64 secured to the fitting34 above the valve stem 30. rlhe cooling air flows down in a space between the stem and the interior surface of the hollow stem 30 and into the -chamber 68 between the bell 2 and cover 8. This air cannot escape to the hot blast main through pipe 20 because of the Huid seal, but can leak out between the surfaces 9 and y11 to the hot blast stove which is not a disadvantage. When the valve is in open position, Fig. 2, the entrance of cooling air from pipe 62 will automatically be prevented because the pressure in the hot blast main 20 is substantially the same as that which is sup lied to the pipe 62.

',rom the foregoing it will be apparent that when the valve is closed no pressure can escape from the pipe 20 to the flue 22 because of the liquid seal, and that all parts exposed to excessive heats are lined with prebrick or other refractory material, that it is unnecessary to carry cooling water to the valve seats or valves which is liable to be carried into the blast furnace in the form of moist air or vapor.

The valve could be employed where pressures lower than those common in blast furnace practice are encountered and any suitablefluid other than mercury can be used for the seal. For higher temperatures a metal or fluid with very high melting point and high boiling point, such as tin could be edectively used. rlhe valve could also be designed tol withstand a greater pressure be'- low the bell than that encountered in usual blast furnace operation, either by increasing thevweight of the bell and associated parts to odset such pressure, or by the provision of locking means to hold the bell in place.

The terms flue and pipe used herein are Menace Aintended to include any main, conduit, pasiag or tunnel used for conveying air, gas or Though l have described with great particularity of detail the embodiment of my invention, yet it is not to be understood therefrom that the invention is restricted to the particular embodiment disclosed. Various modifications thereof in detail and in the arrangement of parts and the substitution of equivalents may be made by those skilled in the art without departing from the invention as defined in the following claims.

What l claim is:

1.. rlhe combination with a flue and a pipe communicating therewith of a valve structure including a vessel surroundinfr a portion of said Hue and containing a fluid, a bell forming part of said valve structure sha ed to enter said vessel to prevent leakage etween said pi e and said flue and a cover lined with re ractory material operatively connected to saidbell and arranged toclose the flue and protect the bell from the destructive action of the air or gases emanating from said line.

2. rlhe combination of a substantially vertical lue and a substantially horizontal pipe connected therewith and forming a space surrounding said flue, said space containing a fluid, of a compound valve including a coveradapted to close the top of said flue and means movable relatively to said cover for entering said space to form a fluid seal to prevent the as or air escaping between the cover and t e due from reaching said pipe 3. The combination of a substantially vertical tlue and a substantially `horizontal pipe connected therewith of a cover having a refractory lining arranged to close communication between the flue andthe pipe, a vessel containing a fluid and surrounding the upper portion ofv said flue, a'bell, shaped to enclose said cover and enter said vessel to form a liquid seal and a. member carried by said bell arran ed to close the end of said pipe when the ellis in its closed position.

4. ln combination with an upright flue and a pipe connected with said ilue at an angle thereto, a valve adapted to control the communication between said flue and said pipe comprising a cover adapted to close the top of said Hue and a member adaptedto close the end of said pipe, a vessel contamin av fluid surrounding the upper art of said lueand a bell surrounding sai cover and movable with said member and adapted vto enter said vessel to positively prevent the escape of air or gas from said pipe to said Hue or vice versa. v

.5. The combination with a ue and a pipe connected therewith and arranged at an angle thereto of a duplex valve comprisin a cover adapted to close the end of said ue and aA member adapted to close .the end of said pipe, means for lifting said member operatively connected with said cover whereby said member is lifted higher than said pipe and said cover is lifted to a plane substantially in alignment with the top of saidpipe.

6. The combination with an upright flue and a lateral pipey connected therewith of a member adapted to close the end of said pipe, a cover adapted to-close the top of said flue, a hood above said flue and pipe to prevent the escape of air or gas when said member and said cover are moved to open position, a tubular lifting device connected to said member, a stem extending into said tubular lifting device and arranged to position said cover in a plane substantially in alignment with the top of said pipe when said member is lifted to its extreme position so that the cover protects said. hood from the destructive action of theair or gases flowing `said cover 1n plane substantially in alignment with the top of said pipe when said member is lifted to its extreme position so that the cover protects said hood from the e destructive action of the air or gases conveyed by the lue and pipe, and means for supplying air to said tubular device to cool 1t and its associated parts.

8. rlhe combination of a flue and a pipe connected therewith and arranged at an angle thereto, of a duplex valve comprising a cover adapted to close the end of said flue, a

,member comprising a bell'having a closed top and arranged to enclose said cover in its closed position, a vessel surrounding the upper end of said Hue and containing a fluid and arranged to receive the lower end of said bell to form a seal, lifting means operatively connected with said member and said cover and so arranged that when said member is lifted higher than said pipe the cover will be lifted to such position that its under-surface will lie in a plane substantially 1n alignment with the inner surface of the top of said pipe.

En witness whereof, I have hereunto signed my name.

SSRN.

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