AU8317282A - Valve controls metal flow from vessel - Google Patents

Description

Form 4

A AI IALI 7

S TWENTY D L-ApjRS CONN 84?A4%NT Here insert (in PATrNT full) Narm Company.

IC, Oft it) were USS EGINEER'TND'ONSULTNTSC.INC. f2) IHere I, nsert (in insert title full) Name IJ or Names of W e 0 of Inventjo Applicant or Npicants, of 601 Q r rn ixt... tet Pt~ii1o it agh taeo 4 000

followed by 0 oAddress (es). 0 tp Pennsylvania United State.... of Amer. ca. 00 0 Here 1 0 0 insert full D at, and Addrcs: of Crnpan' official authorized to make declaration. er~~e lrby apply for the grant of a Patent for an invention entitled: (21 0 0 SVALVE SUITABLE. FOR CONTROLLING.TER-M.NG FRQN FURN 00 or. 00 o 0 00

1Here 0 insert basic 0 0 Country or Countries (3 Here Insert which is described in the accompanying complete specification. This application is a followed by date or date of basic and basic aippleationis)(8 Applicant o Applcants. Convention application and is based on the application numbered

Name of basic Country or(4 Countries, and for a patent or similar protection made in e basic date or dates

"on -1s t-M y--1981 full) Nam of Actual ItiVentor or Mnentors. 7-

Our adesfrsriei Messrs. ruwu. YWaers Sons, Patent Attorneys, -Queen Street, Melbourne, Victoria, Australia.

MI VSAMP TO VAWX OFl

MAL i J DATED this day of April

ture Sgina- of U$S,~NII~ES...AND. CONSUIANTS, INC. __y Applicant (s) Sealof

by prescribed by Its Articles of Association. Stephen K. Plymin Reg'd. Pztent Attorit (6I)Signalti ay

irm

ILL- -ri tWlkj~ 3 .2~

Patents Act 1952-1969, DECLARATION IN SUPPORT OF A CONVENTIONJ APPLICATION FOR A PATENT OR PATENT OF ADDITION

In suppd',rt of t~e Convention Application made by(' e) full) Name of Company. .USES...ERMGNEZZ Q.SLA.S..

(hereinafter referred to as the applicant) for a Patent" of H-ere insert title for an invention entitled 0 of Invention. 000 .ALVE SU..LEO QTRLIG EMIN( FROM FURNACE C Q (S 0

00 R L S TA Here 0 insert full Name en and Addrcs, of CC)mpany of. 6.0. Grat....S.treet Pit-m~hrg 4 SIt t f Penn syll An officia authorized to make Uuite Sa.1es.. Q ca. 1 declaration. do solemnly and sincerely declare as follows: 0 1. 1 am authorised by the applicant for the patent 00 to make this declaration on its behalf. 2. The basic application as defined by Section 141 of the Act was 0 0 U .(4)Hr insert basic Country or made in(4 U n ited K ingd Countries followed by date or dates and basic Applicant or Applcants. on the we 1 .t da of

3 .()KENNETH WILLIAM BATES, of 10Q Orchid Close, Callow. inet '5(in ere utllf Nam and Addrs of Actual Chesterfield, q.-i WLLIAM ALBERT GRIFFITHS, Inventor or Inventors. 10 sb. Roa.. Newbold Chesterfield Derbyshire En...K~gland and NORM1AN HENRY WATTS, ()of 9 Burlington Grove, Dore,Sheffield S17 3PYH, Enad i /are the actua inventor s of the invention and the facts upon which the applicant is entitled to make the application are as follow: The applicant is the assignee d...QGATES LIMI*T'E*D who in turn are the assignee of the said actual in evn to

4. The basic application referred to in paragraph 2 of this Dedaration,- the first application~ made in a Convention country inK respect of the invention the subject of the application. DECLARED at Pittsbu.R#:§ rgh. Pensyvaia U this 23rd day of.June ,1

Signature.

at I

(12) AUSTRALIAN PATENT ABSTRACT (19) AU (11) AU-A-83 172/82

(54) VALVE CONTROLS METAL FLOW FROM VESSEL (71) USS ENGINEERS AND CONSULTANTS, (21) 83 172/82 (22) 30.4.82 (24) 1.5.81 (31) 8113519 (32) 1.5.81 (B3) jB (43) 4.1. 82 (51) 3 F27D 3/14 F16K 3/02 F16K 3/16 F16K 31/44 (72) KENNETH WILLIAM BATES, WILLIAM ALBERT GRIFFITHS AND NORMAN o (0INRY WATTS

(74) WM (57) Claim

1. A valve Inechanism for controlling metal

flow from a vessel outlet, comprising an orificed

stationary valve plate, a companion slidable valve plate

for covering or exposing the orifice of the former to

close or open the valve to flow, an actuating member

extending obliquely to t.hs slidable plate for moving the

slidable plate, spring means acting to bias the i

actuating member again-t the sli plate to press

the slidable plate to the stationary plate, and means

guiding the actuating member for displacement along a

o predetermined path wherein a portion of the actuating

member engaging the slidable plate moves in a plane parallel to the contacting faces of the valve plates.

D1 /3 23

30/24 -J signa- ture of Applicanlt (0) Seal of Cpmpany and prescribed bY its Articles of ASSOtlaticOn.

0

Form COMMONWEALTH OF AUSTRnALIA

PA~TENTS ACT 1952-69

COMPLETE SPECIFICATION (ORIGINAL)

Class Int Class Application Number: Lodged:

tbmplete Specification Lodged: Accepted: Published: Pfiority:

heated Art:

p. an *0

ane of Applicant: USS ENGINEERS AND CONSULTANTS, INC.

,Address yf Applicant: 600 Grant Street, Pittsburgh, State of Pennsylvania 15230, United States of America

::.a,Actual Inventor: KENNETH WITLLIAM BATES, WILLIAM ALBERT GRIFFITHS and NORMAN HENRY WATTS

EDWD. WATERS SONS, Address for Service: 50 QUEEN STLIREET, M.EMBOURNE, AUSTRALIA, 3000.

7.'Comnplete Specification for the invention en,"itled:

VALVE SUITABLE FOR CONTROLLING TEEMING FROM FURNACE TAPHOLES

The following statement is a fult.: description of this invention, including the bqst method of performing it known toy US tue s)o UU E~NGINEERS N D CONSUL'TANTS, Applicant or INC. $eal of Cqumpany and -A~tures 1

4.prescribed itocers as by Dy Its Articles of Assocition.Stephe-n K. Plyrnin Patent/2' 6)Signatur -~Reg'd. PaetAtt rey To:

-m r

ass- I'

r~

-AVE UIABEb COTOLIGrrM

FRO FUNC TAPHOLES

abl for co t o l n tee in fr m a v s e ul t1 suhasafrnc apoe

aas th-unc stle.Te ea n lgte av u Thepreen inetoJreltst ut

a 10 adle. The preente inventgin ratneroablve suitve-

iesuc. asTahurnac itaphl e.avnaeu ob bet mt

asthe furnaceo is tilte.Thmetal and lage then run

ade.Th proving ofe sfarisac conideabtple lcve- enll Thstdheago belool to os beref bleati to emptyof 'the frae molten t metal and func twheav the stle.Sg

form of stopper is needed to close the taphole until po~ring is'to take place. Better still would be a valve openable and &eosable at will, for this would facilitate 2 us 425

4. The basic application referred to in paragraph 2 of this WNTS., the first application made in a Convention country in respect of the invention the subject of the application. DECLARED at .PittsbUrgh2 Pennsylvania, U.Si. A. of..ne 19.. Sgnature. ey 6)

A

the filling of several ladles from one furnace charge,

and the furnace would only need tilting once, at the

start of the emptying operation.

In principle a sliding gate valve might appear

suitable for controlling flow out of the taphole.

However, no known sliding gate valve is suitable. The

known valve mechanism occupy considerable space to eith-rl

side thereof i.e. along the direction of movement of

the sliding valve plate. Adequate space is absent in

the region of a furnace taphole, however, in part due to

the presence of the pouring trough.

An object of the present invention has been to

adapt the sliding gate valve concept to suit a furnace

taphole arrangement, and a mechanism has been devised

in which the sliding valve plate is biased towards the

taphole and is moved to and fro from above the trough.

According to the present inventic'-- there is

provided a valve mechanism for controlling metal flow

from a vessel outlet, comprising an orificed stationar:l'

valve plate, a companion slidable valve plate for

.,;covering or exposing the orifice of the former to close

or open the valve to flow, extending obliquely to the

slidable plate for an actuating member moving the slid-

able plate, spring means acting to bias the actuating

i member against the slidable plate to press the slidable -3-

*rr

I

plate to the stationary plate, and meang guiding the

actuating member for displacement along a predetermined

path wherein a portion of the actuating member engaging

the slidable plate moves in a plane parallel to the

contacting faces of the valve plates.

Although the present valve has been devised

particularly with furnaces in mind, it has application to

other vessels. Thus, the compact form of the valve and

the location, to one side of a vessel teeming opening,

of its structure for biassing and for moving the slide

plate to and fro may be found of significant convenience

for some ladles, tundishes and other vessels from which

molten metal is to be teemed.

The invention will now be described in more

detail by way of example with reference to the accompany-

ing drawings, in whichb Fig. 1 is a front elevation of an arc furnace

fitted with a taphole valve mechanism according to the

invention;

20 Fig. 2 is a side elevational view of the

equipment shown in Fig. 1;

Fig. 3 is an enlarged sectional elevation of

the valve arrangement and ducting leading thereto from

the taphole; and

-4-

t sM ^|EB

4,

Fig. 4 is a diagrammatic geometrical analysis o)f the valve mechanism. Referring first to Fig. 3, a taphole insert is positioned in a furnace taphole, the insert 10 having a flow passage of oval eross-section. Abuttingly sealed to the taphole insert 10 is an intermediate duct S11 having a flow passage which changes from oval to circular cross section. A noizle piece 12 is cemented into the duct 11 and a valve generally designated 14 is

disposed at the end of the nozzle piece 12 remote from the taphole, and is sealed thereto. In essence, the valve 14 comprises a stationary apertured valve plate 15 of ring form and a slide plate 16 of disc form biased thereagainst. Clamps 17 (Fig. 1) secure the plate 15 in abutment with nozzle piece 12. The slide plate 16 is movable in an upward direction, to .uncover the opening 18 in the stationary plate 15 and thus open the tapping channel, by an actuating member Swhich is also arranged to thrust the plate 16 against the plate 15. When the tapping channel is opened by raising the slide plate 16, metal flows from the furnace through the taphole insert 10, the intermediate duct and the stationary plate 15, issuing from the latter into pouring trough 21. Metal flows then down the trough into the receiving vessel or ladle. i

:4"

0 fh~b

When the slide plate 16 is shifted upwardly to open the valve 14 completely it travels a distance almost equal to its diameter. The width of the ring-shaped plate that is the difference between its inner and outer radii, is substantially smaller than the aforesaid distance. Means is therefore provided to support the slide plate 16 as it is moved upwardly. The said means is a thrust plate 22 mounted adjacent the plate 15 on a frame member 23 of the valve. The thrust plate 22 and stationary plate 15 have coplanar slide plate con- tact surfaces 24, The valve mechanism will now be described with particular reference to Figs. 2 and 3. The actuating member 20 for the slide plate 16 performs two functions. First, it biases the slide plate 16 against the stationary plate 15, thanks to spring means 25 acting on the actuating member. Secondly, it operates to displace the slide plate 16 when an actuator 26 is suitably energised. The actuator member 20 is a beam forming part of a linkage 28 so designed that the lower end of the actuator member moves in a vertical path as the actuator 26 is operated. As illustrated, the actuator member 20 is inclined to the vertical, and to frame member 23, and has its lower end copuled to the slide plate. The S- 6 coupling comprises a pin 30 which is received in a yoke t

31 forming part of a shoe 32 mounted in a recess 33 in s

the slide plate 16, see Fig. 3. At an intermediate point along its length, the B

actuator member 20 is pivotally secured to a lever 34 fast with a pivot shaft 35 journalled to a second frame oE member 36 of the mechanism. a The actuating member 20 extends beyond lever TY

34 and has its upper end 38 coupled to the frame member w

23. The spring means 25, which constitutes a spring 10 Pi link, couples the beam to the frame member 23 by way of t

a lever 39 and toggle arrangement 50, to be described. c3

The spring means is pivotally connected at its opposite di ends to the lever 39 and en: 3,8, respectively. ul

The spring means 25 is a device comprising a multiplicity of compression springs, e.g. ten or twelve, ai

which are threaded on a corresponding plurality of 4

bolts holding a pair of thrust plates 42 together. The t

thrust plates 42 each have a projecting eye or clevis 43 2

by which the spring means is secured to lever 39 and the s end 38. In the operative condition shown in Fig. 2, the spring means is in a state of compression, and tends t

to rotate the activating member 20 anticlockwise about 0:

its pivotal connection with lever 34. Thus, the lower end of the actuating member 20 is biased towards the 25 2 taphole, and the slide plate 16 is thrust into firm, sealing contact with the stationary plate

The spring means 25 could include a set of

Bellville washers instead of coil springs if desired,:

For displacing the slide plate between its

open (raised) and closed (lowered) positions, the

actuator 26 is linked via a crank 46 to the linkage 28.

The crank 46 is fast at one end with the shaft 35 on

which the lever 34 is also fast. The actuator 26 is

pivoted to the opposite end of the crank 46 and when

this end is displaced upwardly, the shaft 35 is rotated

clockwise and with it lever 34. This action serves to

displace the actuator member 20 and the slide plate 16

upwardly, to open the valve.

As shown in the drawings, the actuator 26 is

an hydraulic or pneumatic ram. This has its piston rod

47 pivoted to the crank 46 and its body 48 remote from

the piston rod pivoted to a lug 49 on the frame member

23.

Use of such an actuator is conventional in the

sliding gate art, but other actuators could be substi-

'tuted. For instance, the crank 46 could be actuated by,

or even replaced by, an appropriate manual.ontrol lever.

The linkage 28, comprising actuating member

20, lever 34 and spring means 25, acts approximately as a parallel motion device. The geometry.:of lever 34 and one spring means 25 is such as to constrain the actuating thr member 20 to move substantially parallel to itself. By val this means, the lower end of the actuator moves vertically Thi with the slide plate and changes in thrust which it man exerts upon the slide plate 16 are kept within safe 54 bounds as the latter is moved vertically by the actuating 56 member the The spring means 25 acts as a swing link in the The linkage 28. It swings, in the same direction as the the lever 34, about an anchorage 51 at the free end of lever wis 39 which is pivoted at 52 to the frame member 23. In by normal use, however, the lever 39 is barred from pivoting for about the pivot at 52 by the toggle arrangement 50. The Hav effort developed by the spring means 25 tends to rotate act lever 39 anticlockwie about 52. Such rotation is all prevented, however, by the toggle 50 acting as a rigid bia brace between the lever 39 and frame member 23, thanks as to the toggle bearing against a stop 53. Overcentering of the toggle would be necessary if the lever 39 were to aps move in the opposite direction about 52, so this movement -sir is resisted and moreover is positively prevented by a the removable safety pin 54. In normal usage the parts retain eq the -onfiguration shown in Fig. 2, when the anchorage 51 S U i25 anc is fixed.

On occasion, it will be necessary to replace one or both the plates 15, 16. The spring-developed thrust on plate 16 normally exceeds 5 tons, in the valve-closed setting and must be released for servicing. This is accomplished by freeing the anchorage 51 by manipulation of the toggle 50. First, the safety pin 54 is removed. Then, crowbars 55 are located in bosses 56 at the ends of a rod passing through the centre of the toggle 50, and forming the centre pivot thereof. Thereafter the crowbars are levered so as to overcentre the toggle 50 and allow the lever 39 to swing anticlock- wise about its pivot at 52. This movement is accompanied by relaxation of the spring means 25, which can then for convenience be disconnected from the anchorage 51. Having released the spring biasing in this way, the actuating member 20 can be swung away from the valve allowing clear access thereto. Restoration of the spring biasing is in substance"'a reverse of the foregoing steps, as will be recognised. In the present embodiment, the linkage 28 only approximates to a parallel motion device. This is -since the connections between the actuating member the lever 34 and spring means 25 do not move in arcs of equal radius about centres through the shaft 35 and anchorage 51. The geometry of the system, that is the respective lengths of lever 34 and spring means coupled with the positions of their swing centres through 35 and 51,,act to minimise changes in the oblique attitude of the actuating member 20 as the actuator 26 is extended or contracted. As a result, the biasing thrust acting on the slide plate changes but only within safe limits and is at a maximum when the valve 14 is closed. Example

A specific example of the geometry of a tap- hole valve system according to this invention is presented in Fig. 4 of the drawings. In this example, the valve slide plate has a diameter of the order of 335 mm and a throw, or travel of 320 mm between valve-open and valve-closed settings. The spring means 25 comprises twelve compre- 'i ssion coil springs, is 385 mm long when relaxed and 360 imm long when compressed. The load on each spring is 9,50 lbs (431 kg) and the springs push the thrust plates 43 apart with an aggregate force of 5 tons (5080 kg). With the left hand face A of frame member 23 and the centreline B of the pouring passage as datums, the mechanism has the following dimensions:

11

L

The distance between the two pivot axes of lever 34 is 632 mm and pivot axis through shaft 35 is centred 600 mm above B and 214 mm to the right of A; in the normal operative condition, the pivot axis through the anchorage 51 is centred 1116 mm above B and is 332 mm to the left of A;

pivot point 52 of lever 39 is situated 80 mm to the left of A and 1368 mm above B;

,he toggle 50 is connected by a pivot pin to a lug 58 fast with the frame member 23; the

pin is centred 80 mm to the left of A and 1017 mm above B. The connection between the toggle 50 and the lever 39 is 248 mm from pivot point 52, the distance between the latter and the centre of the fixed anchorage being 356 mm. The links of the toggle each have their two pivot apertures 125 mm apart; and the actuator member 20 is 1100 mm long, the lever 34 being pivoted thereto at a centre 580 mm from the centre of the attachment of spring means 25 thereto and 520 mm from the pin 30 coupling the actuating member 20 to the slide plate 16; the pin 30 is centred 170 mm to the left of ;i 12

^)l

In operation, when the lever 34 is swung clockwise or anticlockwise on the shaft 35, the actuating member 20 is displaced substantially parallel to itself, the motion of its lower end being confined to a vertical plane. The pivotal connection between the lever 34 and the actuating member moves along arcuate path C, while the pivotal connection between the spring means 25 and the actuator moves along the approximately parallel arcuate path D. The force exerted by the spring means 25 on *c the actuating member 20 normal thereto is at a maximum

in the valve-closed setting. When the valve is opened, the normal resolved force falls, owing to the swinging motion of the spring means 25 about anchorage 51 reducing the angle between the spring means and the longitudinal axis of the actuating member 20. It follows that the force applied in a direction normal to this axis by the actuating member 20 on the slide plate 16 similarly drops as the valve 14 is opened. The following tabulation gives the forces applying as the slide plate is raised from its valve closed settingo(l) to the limit of its travel through evenly-spaced intermediate positions.

D S-/3 23 /3 23

I /24,

Position Force of spring Force notmal Thrust on slide means on to actuating plate resolved actuating member exert- norial thorctc member normal ed on slide thereto plate Tons kg Tons kg 'rs kg 4

9 2.59 2631 2.89 !2936 b''2 2662

8 3.15 3200 3.51 356 3.15 3200

7 3.60 3657 4.02 4084, 3.55 3607 r

cI 6 3.98 4043 4.44 4511 3.90 3962

4.34 4409 4.84 4917 4.25- 4318 4 4.60 4674 5.13 5212 4.50 4572

4.74 4816 5.29 5375 4.66 4735 2 4.85 49? 5.41 5497 4.80 4877 S 4.94 5019' 5.51 5598 4.95 4663

In this example, the mechanical advantage of the actuating member 20 is 580/520 of 1.115. From the foregning it will be appreciated that the means for biasing the slide plate 16 into sealed contact with the stationary plate 15 and the means for Sdrawing the slide plate 16 aside to open the valve 14 are disposed to one side of the mechanism, and to one side of the pouring passage. The valve arrangement commends itself for any situation where space to one side of a pouring passage is limited. Thus, Use of the

I

arrangement is not confined to furnace taphole control.

Various modifications will be apparent to the

addressee. For example, the actuator could act other-

wise than through lever 46 and shaft 35 for displacing

the linkage 28. Thus, as one possibility the actuator

could be coupled to the pin 30. In principle, the spring

means 25 could act on the actuating member 20 at any

point thereon between lever 34 and the slide plate 16,

the spring means then functioning in tension. The

positions of the lever 34 and the spring means could

then be interchanged.

In the specific embpodiiient the linkage is so

designed that the bottom end of the actuating member

travels vertically. In a modification, the linkage

28 could be replaced by a vertically-extending :ide

in which the bottom end of the actuating member 20 moves.

The; furnace/valve arrangement has the valve 14

and its mechanism located between the furnace wall

and the trough 21, the valve being connected by suitable

ducting to the furnace taphole. Attachment of the

valve mechanism to the furnace wall can be accomplished

in various ways and no description of the attachment

appears warranted here.

i Yj

Claims (1)

1. member against the slidable plate to press the slidable -3-

   ii

   The Claims Defining The Invention Are As Follows:-

   1. A valve mechanism for controlling metal

   flow from a vessel outlet, comprising an orificed

   stationary valve plate, a companion slidable valve plate

   forcovering or exposing the orifice of the former to

   close or open the valve to flow, anactuaing member

   exten ding obliquely to the slidable plate for moving the

   slidable plate, spring means acting to bias the

   actuating member against the slidable plate to press

   the slidable plate to the stationary plate, and means

   guiding the actuating member for displacement along a

   predetermined path wherein a portion of the actuating

   member engaging the slidable plate moves in a plane

   parallel to the contacting faces of the valve plates.

   2. A mechanism according to claim 1, wherein

   the guide means for the actuating member is a parallel

   motion device, whereby the oblique attitude of the

   actuating member is preserved during displacement thereof

   for opening and closing the valve.

   3. A mechanism according to claim 1 or claim

   2, wherein the guide means for the actuating member i's a

   linkage of which the actuating member is part, the link-

   age comprising a pair of oscillatingly movable levers

   each pivotally connected to the actuating member and to

   j,,i;upport structure of the mechanism.

   16 j

   I I

   4. A mechanism according to claim 3, wherein

   one of the levers is a spring strut and constitutes

   the spring means which biases the actuating member

   against the slidable plate.

   5. A mechanism according to claim 4, wherein the spring strut is pivoted to an anchorage which is carried by the support structure and which is braced there-

   to by a toggle linkage, the latter being operable to

   release the anchorage and thereby relieve the biasing of

   the spring strut on the actuating member.

   6. A mechanism accordinj to claim

   the anchorage is on a lever pivoted to the support

   structure but normally barred from pivoting by the

   toggle linkage.

   7. A mechanism according to any one of claims

   4 to 6, wherein the spring strut acting on the actuating

   member is in a state of compression and is located

   further from the slidable plate than the other lever of

   the linkage.

   8. A mechanism according to any one of claims

   3 to 7, wherein the pair of levers have such lengths, and

   their pivotal connections with the support structure are

   so located relative to the plane of the contacting faces

   0 of the valve plates, that the oblique attitude of the

   actuating member is preserved when displaced to open or

   close the valve.

   At

   9. A mechanism according to any one of

   claims 1 to 8, including an actuator operable for dis-

   placing the actuating member. A mechanism according to claim 9, wherein

   the actuator is an hydraulic or pneumatic ram. 11. A mechanism according to claim 9 or claim

   when dependent on any one of claims 3 to 8, wherein

   the actuator acts on a crank fast with a shaft on which

   one of the levers pivotally connected to the actuating

   member is also fast, said shaft being journalled to the

   support structure.

   12. A valve mechanism for controlling metal

   S. o flow from a furnace taphole, substantially as herein

   'described with reference to and as shown in Figs. 1 to

   3 of the accompanying drawings.

   13. A valve mechanism for controlling metal

   flow from a furnace taphole, substantially as herein

   described with reference to and as shown in Figs. 1 to

   3 and 4 of the accompanying drawings.

   14. A furnace having a taphole in its wall, a

   pouring trough for conveying metal teemed through the

   taphole to a receiver vessel, and a valve mechanism

   according to any of the preceding claims located between

   the taphole and the trough, the actuating member extend-

   ing obliquely and upwardly away from the trough and the

   -I

   spring means and guide means being located on the

   opposite side of the slidable plate from the pouring

   trough.

   DATED this 29th day of April 1982.

   USS ENGINEERS AND CONSULTANTS, INC.

   EDWD. WATERS SONS PATENT ATTORNEYS QUEEN STREET MELBOURNE. VIC. 3000.

   19

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