US2215872A - Blast furnace construction - Google Patents

Description

Filed Aug. 27, 1937 3 Sheets-Shet 1 SCHEDULE Limi i Swift/1 seamed (o w,- closeaf when small bell is closed. Lz'mz'f Switch 39*biased in open,- clos'ea when bypass 251': Open. Lz'm! z 52w ch 4 016z'ased i0 qben; closed when bypass 25 is closed Ltmii \Swz'ach 4]- fiiased i0 Closed,- 7

open whgn by-pass 251's open. j /45 5 Limit swzkh 42-bz'ased V ?Z\ to closedqm when y- QQ- Pass 25 5 closed. 46 16 7 rNvsN'roRs Fl 1 Gordm 1 0x OwenREiCe Arfiwr J M011 zc omb 7 "flaw:

3, Shuts-Sheet 2 G. FOX ET AL l ile d Aug. 27, 1937 BLAST FURNACE CONSTRUCTION SQpt. 24, 1940.

Sept. 24, 1940.

G. FOX ET AL BLAST FURNACE CONSTRUCTION Filed Aug. 27, 1937 3 Sheets-Sheet 3 v Gal-$2 A g Wh'z a Y 7' U! 1 com 7 ATT RNEYS Patented Sept. 24, 1940 UNITED. STATES PATENT OFFICE Rice, Chicago, 111., aasignors to Freyn Engineering Company, Chicago, 111., a corporation of Maine r i Application August 21, 1937; Serial No. 161,226

4 Claims. (01. ace-27) The present invention relates to improvements in blast furnace construction.

In blast furnace construction it is common practice to provide a small bell and a large bell t in series at the tend the blast furnace. Ma-

terial is deposited on the small bell. Said small bell while the large bell is closed is dumped to discharge the material upon the large bell. After the small bell has, closed, the large bell is dumped ill to discharge the material into the furnace. In order to prevent the escape of gas from the furnace to the atmosphere, the large bell should be opened only when the small bell is closed and the small bell should be opened only when the largebell i5 is closed. At times the pressure within the furnace is considerably higher than atmospheric pressure. At such times it is sometimes diillcult to cause the large bell to open, as the pressure within the furnace may be suflicient to hold the large bell in 20 closed position even though the cable for operating said large bell is slackened. After a short interval there may be a leakage of gas from the furnace into the space between the bells, after which the large bell will open suddenly, causing as an impact condition.

It has been proposed to push downwardly on the large bell in order to cause the large bell to open even when the gas pressure is high. However, very decided practical disadvantages have so been encountered in such practice.

According to the present invention a by-pass is introduced connecting 'the top of the furnace chamber with the space between the large bell and the small bell. A valve is inserted in this 5 lay-pass in order to prevent the flow of gas from the lurnace to atmosphere when the small bell is open. According to the present invention this bay-pass valve is controlled in response, inter alia, to the'operations of the large bell and thesmall at bell. The present invention also contemplates interlocking means such that the bells may be opened only when the by-pass valve is in proper position. i

An object of the present invention is to provide a blast furnace construction having means for equalizing the pressure upon the two sides of the large bell when it is desired to open said large bell, this equalization being produced by simple and relatively inexpensive means. As a corollary of this object, a further object is to provide mechanism by means of which the control of this equalization will be responsive to the position of the large and small bells. As a further corollary, it is a further object to interlock the means for accomplishing the equalization referred to with the bell operating means, to the end that the bells may be operated only when a condition of equalization has been accomplished.

o A further object is to provide a blast furnace by the cable it, which in turn is operated by the construction well adapted to meet the needs of commercial operation. 2 Further objects will appear as the description proceeds.

Referring to the drawings- 5 Figure 1 is a diagrammatic view illustrating one embodiment of the present invention;

. Figure 2 is a wiring diagram illustrating some of the electric circuits involved in the disclosure of Figure 1.;

Figure 3 illustrates a detail of construction;

Figure 4:. is a view in side elevation illustrating a slightly different construction of the top of a blast furnace from that shown in Figure 1; and

Figure 5 is a fragmentary view, in section, illustrating a self-cleaning valve which is well adapted for use in connection with the construction shown in Figure 4. 1

The numeral it indicates a blast furnace provided with the large bell ill and the small bell it disposed in series; The large bell ii is connected by means of the cable it to the lever M,

which by means of the cable it is connected to the hoist it. The hoist it may be of any of the well known types, though it is at present preferred to use the type known as a hydraulic hoist, which may be 011 operated or pneumatically operated. In the specification the term hydraulic" is sumciently broad ta cover both 011 and air. The hydraulic hoist It is controlled by means of the tour-way valve H, which in turn is operated by the motor it.

The small bell ii is adapted to be operated by the sleeve 59, which is pivotally connected to the lever 20. Said lever til is adapted to be operated hydraulic hoist 22. Operations of the hydraulic hoist 22 are controlled by means of the four-way valve 23, which in turn is operated by the electric motor 24. It is not necessary to describe the hoists l6 and 22 and the control valves 11 and 23 associated therewith inasmuch as structures suitable for the purpose are fully disclosed in the Fox and Whitcomb Patent No. 1,937,951 and in the Whitcornb Patent No. 1,928,039.

The numeral 25 indicates a by-pass conduit, one end of which is connected to the interior of the furnace chamber adjacent to the top thereof and the other end of which is connected to the space between the large bell II and the small bell l2. Disposed intermediate of the length of the conduit 25 is the by-pass valve 28 adapted to be operated by the segment 21, which segment in turn is operated by the electric motor 28.

The present invention contemplates means whereby the following relationships are had:

(1) An interlock whereby it is possible to open the by-pass valve 25 only when the small bell I2 is closed (2) An interlock to permit the opening or the go small bell l2 only when the by-pass valve 26 is closed.

(3) An interlock to permit the opening of the large bell H only when the by-pass valve 26 is open.

The control of the electric motor for operating the by-pass valve is accomplished as follows, refthe by-pass valve 26 either in a closing movement or an opening movement. In other words, for one direction of rotation of the by-pass valve 26 the series field winding 28b will be connected in circuit and for the other direction of rotation the series field winding 280 will be in circuit. The

connections to the electric motor 23 are controlled within a control box 29, certain features of which, pertinent to the present invention, are disclosed in Figure 2. Associated with said control box 29 is a walking beam type of push button, indicated by the numeral 30, which push 28 button is provided with the switches 31 and 32.

Included within the control box 29 are a pair of relays or contactors 33 and 34. The contactor 33 includes the switch 33a and the operating coil therefor 33b. The contactor 33 includes the switch 34a and the operating coil therefor 34b. Switches 330. and 340. are closed when their-cooperating coils 33b and 34b are energized. Said switches 33a and 340 are open when their cooperating coils 33b and 34b are de-energized. The numeral 35 indicates another contactor involving the switch 35a and the operating coil therefor 35b. The switch 350. is open when the coil 35?) is de-energized and is closed when said coil 35b is energized.

The numeral 36 indicates a limit switch responsive to the position of the lever 20, which controls the small bell l2. Said switch 36 is biased to open position and is closed when the small bell I2 is closed.

The segment 21 is provided with a pair of abutment members 31 and 38 displaced from one another in a direction parallel with the axis of swing of the segment 21. For purposes of illustration the abutment members 31 and 38 have been illustrated in Figure 3 as being disposed in different radial positions with respect to the axis of swing of the segment 21, this illustration being chosen for simplicity of disclosure. In practice it will probably be preferred to have the two abutment members 31 and 33 symmetrically disposed with respect to a plane radially disposed with respect to the axis of swing of the segment 21. Said abutment members 31 and 3B are adapted to contact the limit switches 39 and 4|, respectively, at one limit of swing of the segment 21 and are adapted to contact the limit switches 40 and 42, respectively, at the other limit of swing of the segment 21.

The relationships of the limit switches 39, 4|, 40 and 42 to the remainder of the mechanism is expressed in the following schedule: 39-biased to open; closed when by-pass valve 26 is open.

40--biased to open; closed when by-pass valve 26 is closed.

4|-biasedto closed; open when by-pass valve 26 is open.

42-biased to closed; open when by-pass valve 26 is closed.

The limit switch 39 may be connected in circuit to a control box 43, which may be controlled by the push button 44.- The limit switch 40 may be connected in circuit to a control box 45, which may be controlled by the push button 46. The limit switches 4| and 62 are connected in circuit as illustrated in Figure 2.

The two sides of an electric circuit which are -'connected with the control boxes 29, 43 and 45 are indicated by theplus symbol and the minus symbol The mode of operation of the instrumentalities disclosed in Figures 1,- 2 and. 3 is substantially as follows. When the operator operates push button 46, the limit switch 40 is connected in circuit, and if said limit switch is closed (and provided other instrumentalities not disclosed herein, such as the skip hoist, distributor, et cetera, are in predetermined positions), then a 'control circuit is closed through the'control box 45 to the small motor 24, which operates the four-way valve 23 to inaugurate a cycle of movement of the hoist 22 to open the small bell I2 and to close said small -bell. Means for accomplishing this cycle are disclosed in the Fox and Whitcomb Patent No.

1,937,951 and in the Whitcomb Patent No. 1,928,-

039, above referred to. During-this opening and closing movement'the charge upon said small bell 12 will be discharged onto the large bell I I.

When the small bell 12 starts its opening movement the limit switch 36 is opened. This limit switch 36 (reference being had to Figure 2) controls the instrumentalities within the control box 29. As will appear with more particularity presently, it is impossible for the by-pass motor 28 to operate when the limit switch 36 is open. Therefore the by-pass conduit 25 is maintained closed as long as the small bell I2 is open.

When the small bell l2 has completed its closing movement, the operator may close the switch 3| or 32. Since the limit switch 42 is open when the by-pass valve 26 is closed, nothing will happen if the operator closes switch 32. If, however, the operator closes switch 31, he establishes a circuit through the limit switch 36 (now closed) operating coil 33b and limit switch 41 (now closed) to the other side of the circuit. Energization of the operating coil 33b closes the contactor switch 33a, resulting in energizing the operating coil 3517, thereby closing the contactor switch 35a, completing circuit through the armature 28a and the series field winding 280. The bypass motor 28 is thereby energized to move the by-pass valve 26 to open position.

At the end of the opening stroke of the bypass valve 26 the limit switch 4| is opened, deenergizing the coil 33b, causing the opening of switch 330., de-energizing the series field coil 28c and also de-energizing the contactor operating coil 35b, resulting in the opening of the switch 35a. The motor 28 is thereby stopped.

The lay-pass valve 26 being open, limit switch 39 is closed. Therefore, when the switch 44 of controller 43 is closed, circuit is closed from the plus side of the electric circuit, through the-limit switch 39, causing the energization of the motor 18 which cooperates with the hoist for the large bell II. The large bell then opens and closes in accordance with known practice, examples of which are illustrated in the Fox and Whitcomb Patent No. 1,937,951 and the Whitcomb Patent No. 1,928,039, above referred to. As pointed out in said patents, the large bell ll may be interlocked with the small bell, so that said bells may not be open simultaneously.

Now thatthe large bell l I hasbeen opened and closed, the operator will desire to close the bypass valve 26 so that he can again operate the small bell l2. The small bell cannot be opened when the bypass valve 26 is open, because the limit switch 40 is open when the by-pass valve- 26 is open.

The operator may close switch 32, establishing a circuit from the plus side of the electric circuit through the operating coil 34b and the limit switch 42 (closed when the by-pass valve 25 is open). Energization of the operating coil 34?) results in the closing of the contactor switch 34a, which results in the energization of the operating coil 35b and the'energization of the series field coil 28b. Energization of the operating coil 351) results in the closing of the switch 35a, complating circuit through the armature 28a of the motor 28. Energization of the armature 28a and the series field winding 28b results in the closing of the by-pass valve- 26, thereby completing the cycle oi. operation.

Referring nowto the structure shown in Figures 4 and 5, it will be noted that the furnace i0 is provided adjacent to the top thereof with the uptake 45, which communicates with the interior of the furnace chamber. A by-pass conduit 46 is provided from the region between the two bells and the uptake 45. Disposed in the by-pass conduit 46 is the by-pass valve4i, fora disclosure of which reference may be had to Figure 5.

Said bypass valve 41 includes the housing 48 I providing the conical valve seat 49, which flares outwardly in a downward direction. Cooperating with the valve seat 49 is the valve member 50,

preferably round in plan view, pivoted on its under side upon the swinging end of the lever 5i.

Said lever 5| is keyed to a shaft 52 rotatably j mounted at one side of the housing 48. Said 3 valve member includes the conical surface 53 adapted to cooperate with the conical valve seat 49. Abutments 5454 at the end of the lever 5| 7 limit the swing of the valve member relative to said lever 51. By the construction illustrated,

the valve member may swing sufliciently upon the lever 5! to enable said valve member to pilot itself into proper cooperative relationship with the conical valve seat 49. Said shaft 52 has secured thereto outwardly of the housing 48 the operating arm 55 provided with the weightedmember 56. According to the structure shown in Figures 4 and 5, the operating arm 55 is connected to an operating cable 51, which may be controlled by a motor similar to the motor 28 previously described. In the structure illustrated in Figures 4 and 5, however, the motor 28 may be located close to the ground, where servicing may be conveniently had.

. The structure illustrated in detail in Figures 4 and 5 has the advantage that the valve is selfcleaning. Any dust particles deposited upon the\ upper side of the valve member 50 fall off when said valve member 50 is loweredto its open position. There is no tendency for the dust particles :to cling to the under side of the valve seat 49 V and consequently the valve member 50 audits seat 49 are always maintained in clean condition.

Though a preferred embodiment oi the-present invention has been described in detail, many modifications will occur to those skilled in the art. It is intended to cover all such modifications that fall within the scope of the appended claims. a

What is claimed is l. A blast furnace comprising, in combination, a furnace chamber, a lowermost charging bell and a topmost charging bell at the top of said chamber arranged in series with one another, means for operating the lowermost of said bells, means for operating the uppermost of said bells, a bypass conduit adapted to connect the space between said bells with said furnace chamber,a valve in said conduit, motive means for said valve, and means for interlocking said operating means for the uppermost of said bells with said valve to permit initiation of the opening movement of said uppermost of said bells only when said valve is closed, and means for holding said motive means inoperative throughout the cycle of movement of said uppermost bell.

2. In a blast furnace, in combination, the furnace chamber, a lowermost charging bell, an uppermost charging bell, said bells being arranged in series, operating means for said lowermost bell, operating means for said uppermost bell, a conduit adapted to connect the space between said bells with said furnace chamber, a valve in said conduit, motive means for operating said valve, means responsive to the position of said valve for preventing the opening of said uppermost bell except when said valve is in closed position, and means responsive to the position of said uppermost bell to prevent opening of said valve except when said uppermost bell is in closed position.

3. In a blast furnace, in combination, the furnace chamber, a lowermost charging bell, an upperm'ost-charging bell, said bells being arranged inseries, means for operating said lowermost bell, ea ioroperating said uppermost bell, a conadapted to connect the space between said bellswltn said furnace chamber, a valve in said .nduifi'imeans to open and to hold said valve pen position, means to close and to hold said permit opening of said valve onlywhen said uppermost bell is closed, and limit switches responsive to the open and closed positions of said valve o define the conditions under which the upper and lower bells respectively may be opened.

4. In a blast furnace, in combination, a furnace chamber, a lowermost charging bell, an uppermost charging bell, said bells being arranged in series, means for operating said lowermost bell, means for operating said uppermost bell, a conduit adaptedto connect the spacebetween said bells with said furnace chamber, a valve in said conduit, means to open and to hold said valve in open position, means to close and to hold said valve in closed position, means responsive to the position or the uppermost of said bells to permit opening of said valve only when said uppermost bell is closed, and other means responsive to the open and closed positions of said valve to define the conditions under which the upper and lower bells respectively may be opened.

- GORDON FOX.

ARTHUR J. WHITCOMB. OWEN R. RICE.

, ve in closed position, a limit switch responsive to the position of the uppermost of said bells to

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