US3653647A

US3653647A - Blast furnance top cone and steam control nozzle assembly

Info

Publication number: US3653647A
Application number: US61104A
Authority: US
Inventors: Hugh B Carr; Norman F Bradel
Original assignee: SP Kinney Engineers Inc
Current assignee: SP Kinney Engineers Inc
Priority date: 1970-08-05
Filing date: 1970-08-05
Publication date: 1972-04-04
Anticipated expiration: 1989-04-04

Abstract

A blast furnace top cone and steam control nozzle assembly including a housing mounted on the cone and having an end opened to the confines of the top cone. A nozzle member is supported by the housing at the open end thereof. A stop member is disposed in the housing and is engageable with the nozzle member for selectively opening and closing the nozzle. The steam is shut off at its point of injection into the blast furnace thereby preventing the hot blast furnace gases from entering the housing to cause damage therein. Also, shutting off the steam at the nozzle eliminates a need for a separate steam shutoff valve upstream of the nozzle.

Description

United States Patent 1151 3,653,647

Carr et al. Apr. 4, 1972 54] BLAST FURNANCE TOP CONE AND 3,298,824 l/l967 Grace et al. ..266/31 STEAM CONTROL NOZZLE ASSEMBLY Primary Examiner--Gerald A. Dost Attorney-Parmelee, Utzler & Welsh [5 7] ABSTRACT A blast furnace top cone and steam control nozzle assembly including a housing mounted on the cone and having an end opened to'the confines of the top cone. A nozzle member is supported by the housing at the open end thereof. A stop member is disposed in the housing and is engageable with the nozzle member for selectively opening and closing the nozzle. The steam is shut off at its point of injection into the blast furnace thereby preventing the hot blast furnace gases from entering the housing to cause damage therein. Also, shutting off the steam at the nozzle eliminates a need for a separate steam shutoff valve upstream of the nozzle.

10 Claims, 5 Drawing Figures FATENTEDAPR 4 I972 SHEET 1 OF 3 FIG. 4.

94- CONTROLLER m 4 RD w fin A v e N B 0 E r wa m I ANn MM H N y w B 1 1 I I. 1 1 I 1 1 I I 1 1 1 1 I 1 1 0 1 0 I I 1 1 1 1 u FIG: 2.

INVENTORS. HUGH 5. CAR/?& NORMAN/T BRADEL Attorneys PATENTEDAPR 4 I972 3,653,647

SHEET 3 BF 3v FIG. 3.

4 32- i E fi FIG. 5. H4 ,06 1 51 I02 AUTO ammo/w CLOSING /20 k /30 I26 COIL MANUAL .4

\ 24 INVfA/TORS- HUGH B. CARR 8 I NORMA/V E BRADEL Attorneys BLAST FURNANCE TOP CONE AND STEAM CONTROL NOZZLE ASSEMBLY This invention relates to a blast furnace top cone and steam control nozzle assembly.

During the operation of a blast furnace at large volume of gases is generated. These gases are usually discharged through the top cone of the furnace and directed to a gas cleaning facility where they are cleaned ofsolid and gaseous pollutants and then used as needed or ejected into the atmosphere. The temperature of the gases at the top cone is very high, reaching 1,000 F. and over at times. The high temperatures necessitate careful design of the gas cleaning facility, such design resulting in a costly facility. In addition, the high temperature gases tend to reduce the effective life of the gas cleaning facilities. It is desirable, therefore, to cool the gases to keep down the construction and maintenance costs of the gas cleaning facility. One method used in cooling the gases is to inject steam into the top section of the furnace. The steam is passed through a main steam line to a nozzle arranged in a housing. A steam shut-off valve is provided, usually in the main stream line, for turning the steam on or off. A problem with this arrangement is that the furnace gases are able to enter through the nozzle and into the nozzle housing. The gases, together with being very hot, are laden with highly abrasive dust particles, and thereby erode the nozzle and the interior of the nozzle housing. Because of this, the nozzle and the housing must be frequently serviced or replaced.

We overcome the above problems by providing a blast furnace top cone and steam control nozzle assembly which does not permit entry of hot gases through the nozzle when the steam is shut off. More particularly, our assembly comprises, preferably, a top cone structure shaped to fit on the top of a blast furnace, and including at least one opening for connection with an uptake line for transporting furnace gases to a gas cleaning facility; nozzle means mounted on the top cone for injecting steam into the furnace; and stop means for selectively closing and opening the nozzle means at the point of steam injection. Thus, by shutting off the steam at the nozzle, the damage thereto by the hot abrasive gases is avoided.

Other details and advantages of this invention will become apparent as the following description of a preferred embodiment thereof proceeds.

In the accompanying drawings, we have shown a present preferred embodiment ofthis invention in which:

FIG. 1 is a schematic view in vertical transverse section of a blast furnace top cone and part of the upper section of a furnace with a steam control nozzle forming part of this invention shown mounted on the top cone;

FIG. 2 is a view of the steam control nozzle partly in longitudinal section and showing a sectional part of the furnace top cone to which the nozzle is mounted;

FIG. 3 is an elevational view of part of the steam control nozzle of the earlier figures showing a valve arranged between the nozzle and top cone; and

FIGS. 4 and 5 show schematic representations of a temperature control arrangement and a typical control circuit for the automatic control of the operation of the nozzle assembly in response to the gas temperature within the top cone.

Referring now to the drawings, there is shown an upper section of the throat of a blast furnace 10. A top cone 12 having the familiar truncated cone shape is arranged on the top end of the furnace. A familiar small bell hopper 13 is supported in the upper end of the top cone 12, and a large bell hopper 14 is supported by the top cone and extends to a position above the stock line of the furnace. A receiving hopper 15 is arranged in the upper end portion of the small bell hopper 13. A rotatably supported small bell 17 closes the discharge end of the small bell hopper 13, which bell 17 is also supported for reciprocal movement to open and close the discharge of the small bell hopper. A large bell 19 is arranged in the lower end of the large bell hopper 14 and is movable to open the lower end of the large bell hopper 14 and is movable to open the lower end of the large bell hopper for charging the furnace and also to allow furnace top gases to enter into the top cone area. Opening 16 is provided through the top cone and is connected with an uptake pipe 20 for transporting furnace top gases to a gas cleaning facility, not shown, which includes such equipment as a dust catcher, gas scrubber, and the like. After the gases are cleaned they are either ejected directly to the atmosphere or used for various operations such as, for example, heating the air in hot blast stoves or in driving gas engines. Prior to discharge, the gases will at times during the blasting operation reach temperatures of l,000 F. or more. The gases are cooled from the high temperatures by means of steam injected into the throat of the furnace through the top cone.

A nozzle assembly, generally designated by the numeral 30, is provided for injecting cooling steam into the furnace. The nozzle assembly includes a generally cylindrically shaped housing 32 having open bottom and

top ends

34 and 36. A circular flange 38 is fixed to the housing 32 and mates with a flange 40 on top cone 12 for mounting the entire nozzle assembly on the top cone. The

flanges

38 and 40 are attached and secured to each other by machine bolts 42 and nuts 44. Flange 40 is arranged on a section of pine 46 extending outwardly from an opening 35 through the surface of top cone 12. The flange 38 is secured to an intermediate section of housing 32 and at a position thereon 'so that when the flanges are mated the bottom end 34 of the housing is adjacent the opening 35 through the top cone. A steam inlet pipe 39 open to the interior of housing 32, extends radially outwardly from an upper section of housing 32 and includes a flange 41 on the outer end thereof for connection with a flanged main steam line 43 which, in turn, is suitably connected to a source of steam, not shown.

A cap shaped nozzle member 47 made from a suitable material such as bronze, is fixed to the bottom end portion of housing32. The nozzle member 47 has nozzle orifice 48 sized to provide a desired steam spray pattern into the furnace. The inner surface of the nozzle member 47 around the orifice 48 is spherically shaped to seat a plug as will be described hereinafter.

A flange 50 is fixed to the upper end portion of housing 32 to which is secured the lower flange portion 51 of a generally cylindrically shaped adapter section 52. The adapter section 52 has an upper flange 54 to which is secured a limitorque type gear drive assembly 56 of any well known construction. The gear drive assembly may be driven manually by turning the handwheel 58 which is connected to the gear train or by activating electric motor 60 also connected with the gear train. A drive shaft 64 is coupled with the gear train and extends downwardly coaxially through the adapter section 52 and housing 32 and terminates in the lower portion of housing 32. The lower end portion of drive shaft 64 is threaded to receive a plug 66 which is shaped to seat in the spherical surface around the orifice 48 of nozzle member 47. The drive shaft 64 is connected to the gear train of gear drive assembly 56 to permit the shaft and plug 66 to move upwardly and downwardly relative to the nozzle member 47 to close and open the orifice 48. The drive shaft 64 is kept from revolving by means of a sliding key 65 fixed to the shaft and arranged in a keyway 67 of the central tubular portion 69 of a bracket 71 which is fixed to ears 73 extending radially inwardly from the inner surface of adapter section 52.

An elongated tubular body 70 surrounds an intermediate portion of drive shaft 64 and is fixed at its upper portion to a central portion of lower flange 51 of adapter section 52. Body 70 houses upper and lower bushings 72 and 74 which serve to secure the centering of the shaft 64 within the housing 32 to thereby insure the proper seating of plug 66 in orifice 48 of nozzle member 47. Sealing packing 76 is disposed in body 70 above bushing 72 for preventing steam from entering into the adapter section 62 around the drive shaft 64. An adjustable gland nut 77 closes the upper end of body 70 and presses against the packing 76 to compress it for effective sealing.

The orifice 48 of nozzle member 47 may be opened or closed as a result of movement of the plug 66 up or down by activating motor v60 or manually by turning handwheel 58 after disengaging the gear train in the assembly 56 from the motor drive shaft. A clutch lever 90 is provided for engaging or disengaging the gear train from the drive shaft of motor 60.

A temperature responsive control 94 is provide for automatically activating the motor 60 when the temperature of the furnace gases rises above or below a desired set temperature. Thus, if the set temperature is exceeded the control 94 sends a signal to start the motor 60 and the motor is activated to drive the shaft 64 upwardly to unseat plug 66 and open the orifice 48 of nozzle member 47. The motor 60 will run until the plug 66 is in the full open position at which point a limit switch is actuated to stop the motor. When the temperature of the gases decreases to below the set temperature, the control 94 again sends a signal to start motor 60 and the motor will drive the shaft 64 and plug 66 downwardly to close the orifice 48. Another limit switch will be tripped when the orifice 48 is closed to stop the motor 60.

FIGS. 4 and show schematically a typical arrangement for automatically controlling the operation of the nozzle assembly 30 in response to the temperature of the gas within the top cone 12. There is provided a thermocouple 100 suitably disposed within the confines of top cone 12 and suitably wired to the controller 94 which in turn is suitably wired to the motor 60, through gear box 56. The circuitry for the controller 94 is shown schematically in FIG. 5. When the temperature sensed by thermocouple 100 increases to a preset point and switch 102 is closed, a micro switch 104 makes contact completing a circuit through the open limit switch 106 located in gear box 56. The motor 60 is then started to open the nozzle assembly 30. The limit switch 106 stops the motor with the nozzle assembly in the complete open position. The current is then passed through a torque switch 108 which limits the amount of torque motor 60 can transmit to drive shaft 64 when it is travelling toward the open position. Current passes through a normally closed contact 110 which serves as an electrical interlock preventing the normally open contact 112 from being energized at the same time as contact 110. A parallel test circuit including manual switch 114 is provided around micro switch 104. A normally open contact 116 is in the test circuit and the open switch 114 seals in the open contact 116 until either the open limit of switch 106 is reached or the stop button switch 120 of the controller 94 depressed.

When thermocouple 100 transmits a below set point temperature to the controller 94, micro switch 124 will make contact at which time current passes through a closed limit switch 126 to motor 60 which drives the drive shaft 64 to close the nozzle. Limit switch 126 will shut off motor 60 when the nozzle is closed. The current will pass through torque switch 128 which serves to limit the torque that motor 60 can transmit to drive shaft 64. Current then passes through contact 112 which serves to open contact 110. Micro switch 124 has a parallel circuit around it when the controller is put in manual operation by operating switch 102 accordingly. Closing pushbutton switch 130 will energize the motor 60 through limit switch 126. There is another parallel circuit around micro switch 124, and includes a normally open contact 132 that will cause motor 60 to drive the drive shaft 64 to fully close the nozzle. The only way that the closed travel direction can be interrupted is by depressing the stop button switch 120.

FIG. 3 shows the nozzle assembly 30 separated from the top cone 12 by a gate valve assembly 94 of any well known design. The gate valve 94 may 'be closed when it is necessary to remove the nozzle assembly 30 from the top cone 12 for servicing, changing the nozzle member 48, etc.

By controlling the opening and closing of the steam nozzle at the point of injection of the steam into the blast furnace, flow of hot abrasive furnace gases through the nozzle is prevented. This results in a longer life of the nozzles. Also, there is no longer a need for having a separate steam valve in the main steam line. However, if a separate steam valve is used the gear drive assembly 56 should be interlocked with the drive means for the steam valve so as to open the orifice 48 of the nozzle member 47 before the steam valve is opened.

Any number of noule assemblies 30 may be arranged around the top cone 12 to satisfy any desired steam spray coverage. We illustrate only one assembly for sake of clarity of description. it should also be apparent that various other modifications to the structure described may be made and still be within the essence of this invention.

We claim:

1. In combination with a blast furnace top cone including at least one opening coupled with an uptake line for transporting blast furnace gases to gas cleaning facilities; a steam control nozzle comprising:

a hollow housing having one end opened to the confines of the top cone, and a steam inlet;

mounting means for mounting said housing to the top cone;

connecting means for connecting said steam inlet with a steam line;

a steam nozzle means supported by said housing downstream of said steam inlet for directing steam into the confines of the top cone;

stop means disposed in said housing and engageable with said nozzle means for selectively opening and closing the opening of the nozzle means; and

power means for moving said stop means into and out of engagement with said nozzle means.

2. The combination as set forth in claim 1 wherein said nozzle means is supported by said housing at the open end thereof, and the opening of said nozzle means arranged generally coincident with the open end.

3. The combination as set forth in claim 1 including control means operatively connected with said power means and responsive to the temperature of the gases within the blast furnace for activating the power means to open and close said nozzle means.

4. The combination as set forth in claim 1 including valve means disposed between said housing and the top cone for selectively closing and opening the confines of the top cone to the interior of said housing.

5. The combination as set forth in claim 1 wherein the open end of said housing is disposed within the confines of the top cone.

6. A blast furnace top cone and steam control nozzle assembly comprising:

a top cone structure shaped to fit on the top of a blast furnace and having at least one opening for connection with an uptake line for transporting gases to a gas cleaning facility;

nozzle means mounted on said top cone structure for injecting steam within the confines of the top cone; and

stop means engageable with said nozzle means for selectively closing and opening the nozzle means at the point of steam injection.

7. The assembly as set forth in claim 6 wherein said nozzle means includes a hollow housing member fixed to the top cone structure and having a steam inlet disposed between the ends thereof; a nozzle member supported by said housing member downstream of said stream near the top cone so as to direct steam into the confines of the top cone; and said stop means is engageable with the nozzle member.

8. The assembly as set forth in claim 6 including control means operatively connected with said stop means and responsive to the temperature of the gases within the confines of the top cone for activating the stop means to open and close said nozzle means.

9. The assembly as set forth in claim 7 wherein said stop means includes an elongated stop member supported by said housing member for movement longitudinally with respect thereto; and the assembly further including power means coupled to said stop member for moving the stop member into and out of engagement with the nonle member.

10. A combined steam nozzle and valve arrangement for mounting on the top cone of a blast furnace comprising:

a tubular valve body terminating at its lower end in a port of a diameter smaller than the tubular body;

a stem extending axially through the tubular body having a may be connected;

plug at its lower end with a sp fi al urfa a p e to Set a removable plate on the upper end of said body having a tuagalnst and close sald P m i P and bular guide thereon extending down around said stern and upwardly ff from Sam P" the tubular terminating at a spaced distance above said port. said P P P 5 tube having a packing gland around the stem accessible at the said port In combination with the plug controlling the the to ofthe late. nd

ttern of steam emerging from said port' p p a spray Pa means space above and supported on said plate for admeans on said tubular body spaced upwardly from said port for mounting the body on the top cone of a blast furnace;

a pipe connection on said tubular body disposed upwardly 10 from said mounting means to which a steam supply pipe justably moving said stem and its plug vertically between open and closed positions.

l l I! k

Claims

1. In combination with a blast furnace top cone including at least one opening coupled with an uptake line for transporting blast furnace gases to gas cleaning facilities; a steam control nozzle comprising: a hollow housing having one end opened to the confines of the top cone, and a steam inlet; mounting means for mounting said housing to the top cone; connecting means for connecting said steam inlet with a steam line; a steam nozzle means supported by said housing downstream of said steam inlet for directing steam into the confines of the top cone; stop means disposed in said housing and engageable with said nozzle means for selectively opening and closing the opening of the nozzle means; and power means for moving said stop means into and out of engagement with said nozzle means.

6. A blast furnace top cone and steam control nozzle assembly comprising: a top cone structure shaped to fit on the top of a blast furnace and having at least one opening for connection with an uptake line for transporting gases to a gas cleaning facility; nozzle means mounted on said top cone structure for injecting steam within the confines of the top cone; and stop means engageable with said nozzle means for selectively closing and opening the nozzle means at the point of steam injection.

9. The assembly as set forth in claim 7 wherein said stop means includes an elongated stop member supported by said housing member for movement longitudinally with respect thereto; and the assembly further including power means coupled to said stop member for moving the stop member into and out of engagement with the nozzle member.

10. A combined steam nozzle and valve arrangement for mounting on the top cone of a blast furnace comprising: a tubular valve body terminating at its lower end in a port of a diameter smaller than the tubular body; a stem extending axially through the tubular body having a plug at its lower end with a sperical surface adapted to set against and close said port in its closed position and movable upwardly away from said port into the tubular body in its open position; the said port in combination with the plug controlling the spray pattern of steam emerging from said port; means on said tubular body spaced upwardly from said port for mounting the body on the top cone of a blast furnace; a pipe connection on said tubular body disposed upwardly from said mounting means to which a steam supply pipe may be connected; a removable plate on the upper end of said body having a tubular guide thereon extending down around said stem and terminating at a spaced distance above said port, said tube having a packing gland around the stem accessible at the top of the plate; and means space above and supported on said plate for adjustably moving said stem and its plug vertically between open and closed positions.