Патент USA US3093882код для вставки
June 18, 1963 G. A. PAGoNls METHOD OF' AND APPARATUS FOR FORMING AN INGOT OF MOLTEN REACTIVE MATERIAL Filed Sept. 30, 1959 3,093,872 3 Sheets-Sheet l [VALVE VALVE l/NLÚCKEÜ LÜCKED //.///f/// / / / //// // // //,////////// / / // / / / // /// // / // /////// /////////////’/// INVENTOR George Il. Pagazzz's ATTORNEYS June 18, 1963 G. A. PAGoNls ‘ 3,093,872 METHOD oF AND APPARATUS FOR FORMING AN - INGoT 0F MOLTEN REACTIVE MATERIAL /24 . m4 `,Z0 l /44 /za ’04 ma » INVENTOR @forge Ã- Page1135’ ATTORNEYS June 18, 1963 G. A. PAGoNls 3,093,872 METHOD OF‘ AND APPARATUS FOR FORMING AN INGOT OF MOLTEN REACTIVE MATERIAL George il. Pagan/115' EY ¿mW/@maw ATTORNEYS United States Patent 1 3,093,872 METHOD OF AND APPARATUS FOR FORMING AN INGOT OF MOLTEN REACTIVE MATERIAL George A. Pagonis, San Jose, Calif., assignor to Light Metals Research Laboratory, Inc., San Jose, Calif. Filed Sept. 30, 1959, Ser. No. 843,533 13 Claims. (Cl. 22--79) This invention relates generally to an apparatus for handling a molten material for forming an ingot thereof, and more specifically to an apparatus for conducting a high-temperature, molten, reactive material from a point of treatment to a receiving mold for forming an ingot. icc 3,093,872 Patented .lune 18, i953 Z cooled simultaneously with the introduction of a rela tively cool inert atmosphere into the mold. It is a further object of the invention to provide a novel means for selectively heating or cooling an ingot mold. It is a further object of the invention to provide a novel means for positioning an ingot mold in receiving relationship to a pouring spout and for raising and lower ing said mold with relation to the end of sai-d spout. Further, it is an object of the invention to provide means for temperature control Iof an ingot mold to avoid thermal shock to the mold and to facilitate the proper solidification 4of the mol-ten material. Reference is made to applicant’s earlier applications, `Other and further 4objects and advantages of this in Serial No. 505,887, tiled May 4, 1955, for a Process for 15 vention will become more apparent from a consideration Treating Titanium Metals and now abandoned, and Serial of the following specification when read in conjunction No. 775,994, tiled November 24, 1958, for an Appa with the annexed drawings, in which: ratus for Treating Titanium and Other Metals, of which FIG. l is an elevational view showing the relation the present .application is a continuation-impart and now ship of the pouring spout or conduit, the ingot mold, the Patent 3,079,451. These earlier applications relate to a 20 separable valved connection between the conduit and method of and to an apparatus for producing substan mold, a mold-receiving and supporting member, and the tially pure metals and ltheir base alloys in consistent means for raising and lowering the mold, certain parts homogeneity through the use of a novel sequence of op of the cold and mold-receiving member appearing in sec erations in a novel multistage apparatus wherein the «tion and the pouring spout being positioned for the be meta-l is tirst melted yand passed from stage to stage in its 25 ginning of a pouring operation; molten state. As disclosed in these earlier applications, FIG. 2 is a plan View of the separable valved connec the process is carried out by the continuous application tion; of inert gas and vacuum in ra novel manner, »the con FIG. 3 is a sectional View through the separable valved struction of the apparatus ybeing such as to preclude connection taken on the Iline 3_3 of FIG. 2„ showing the entry of the ambient atmosphere at any stage during 30 the valve members in their closed position; the operation thereof. FIG. 4 is a plan view of one of the housings of the While the apparatus of the present invention may be separable valved connection as viewed on the line 4_4 used for torming an ingot of any conventional metal or of FIG. l, lshowing the valve member in its open po alloy, it is particularly useful in the handling of reac sition; tive metals, such as titanium ,and other refractory rnet 35 FIG. 5 is a vertical sectional View through the connect als, which at elevated temperatures have a high aiiinity ing spout or conduit, separable valved connection and for the oxygen and nitrogen in the atmosphere. mold, in one of the mold-iillin-g positions taken on the In the process as described in the earlier-tiled appli line 5-5 of FIG. 2; and cations referred to above, the conditions of vacuum and FIG. 6 is a View similar to FIG. 5, illustrating the inert atmosphere are employed throughout the entire 40 valve elements in their closed position and the housings system, including an ingot mold and connecting spout of the valved connection separated. thereto from a orucible containing the molten metal. A In the description which follows reference will be made, valve is provided in the connecting spout adjacent the for purposes of exempliñcation only, to the productionV of crucible, and this valve normally remains closed except titanium or titanium alloys in which an inert atmosphere during the pouring stage when the molten met-al is trans of helium is employed. lt should be understood, how ferred `from the Crucible to the ingot mold. In the pour ever, that the apparatus and method could also be used ing operation it is important that atmospheric contami in connection with other metals or refractory materials nants be completely excluded from contact with the which are highly reactive at elevated temperatures in their molt-en metal and ingot until the latter has reached a molten state as well as with any conventional metal or nonreactive stage. It is also important that the tempera 50 other molten material, and that other inert gases could be tures of the ingot mold `and poured ingot be carefully employed. The references to titanium, titanium alloy, or controlled, both from the standpoint of prevention of helium in the Specification, therefore, are not intended as thermal shock to the mold liner and for obtaining proper limitations, but are intended to be illustrative of the broad inventive concepts. crystal structure in the cooled ingot. It is .an object of this invention to provide a connec Referring to the drawings, in which identical parts are tion between the pouring spout and the ingot mold, which designated by the same reference characters, the system, effectively precludes the lentry of ambient atmosphere as shown in FIG. l, comprises pouring spout C from a into 4and the loss of the inert atmosphere from the mold Crucible (not shown), a connecting member CM, a mold and connecting spout. M, a mold-receiving member MRM, a platform P, and a It is a further object of the invention to provide a 60 hydraulic jack HI. The pouring spout C is connected at its upper end novel connection between the pouring spout and the mold through a valve to a Crucible, as shown in the earlier whereby to retain both the mold and the connecting sp out filed applications Serial No. 505,887 and Serial No. 775, in sealed condition when the mold is removed from the 994, from which it receives pure molten titanium or titani spout after receiving a charge of molten metal. It is a further object of the invention to provide means 65 um alloy, and the discharge or outlet end, designated by the reference numeral 10, extends vertically downward. for the evacuation of contaminating gases from the mold The spout C includes an outer tubular shell l2, an inner and spout and for the supply of an inert atmosphere lining 14, and an intermediate lining 16. The shell 12 thereto. is formed of steel, while the linings i4 and 16 are formed It is a further object of the invention to provide a 70 of a suitable refractory material capable of withstanding novel separable valved connection between a connecting the high temperatures encountered. conduit and a rnold wherein the valve elements may tbe As shown in FÍGS. 3, 5 and 6, the intermediate lining 3,093,872 l 3 . 16 is slightly shorter than the inner lining 14 and the shell 12, and is held in place by the upper end of a ring 20 of a stop collar 18. The ring 28 is externally threaded 4 As seen in FIGS. 4 and 5, portions of the ribs 58 and 76 are cut away at 96, to receive cam locks 98. Each cam lock 98 comprises a short cylindrical member which is to matingly engage internal threads on the lower end of eccentrically mounted on one end of a shaft 100 extend ‘the shell 12. The lower end of stop collar 18 is pro vided with an internal flange 22 adapted to be received within a rabbet 24 in the lower end of the inner lining 14. The connecting member CM comprises a two-part valve assembly 26 including an upper valve housing 28 `and a ing through the side flanges 40 and 72 of the upper and lower valve housing 28 and 30, respectively, the openings being sealed by means of packing glands 102. The outer ternal diameter to provide a working llt about the outer adapted to extend into these recesses so that when the ends of the shafts 10i) are equipped with operating cranks 104 by means of which the eccentrically mounted cam lower valve housing 3ft. > 10 locks 98 can be oscillated. Springs 106 surround the shaft and act on the cranks 104 and the packing glands 102 The .upper valve housing 28, as shown in FIGS. 2, 3, 5 to urge the shafts 100 outwardly. The cam locks 98 and 6, is rectangular in form, having a flat upper surface have a diameter equal to the width of the channels 56 and including a hollow upstanding boss 32, having a bore 33, 881 in the valve elements 54 and 78, respectively, and are adjacent one end. The bore 33 in the boss has an in surface of the shell 12, and includes a pair of spaced an cranks 104 are oscillated from the .postion shown in solid nulargrooves for sealing rings 34 adapted to prevent leak lines in FIG. l to the position shown in dotted lines, the age of gases between the boss and the pouring spout C. cam locks 98, due to their eccentric mounting on the shafts 100, urge the valve elements 54 and 78 tightly against their valve seats 50 and 92, respectively. The lower edges of the flanges 40 and 42 of the upper The lower end of the bore 33 is rabbeted at 36 to receive an external flange 38 on the lower end of stop collar 18, as shown in FIGS. 3 and 6, to limit the downward ‘sliding movement of the upper valve housing 28 on the outlet end 16 of the pouring spout C. The end of the valve housing 28 adjacent the boss 32 (to the left as viewed in FIGS. 5 and 6), includes a downwardly directe flange 42, and each side is provided with downwardly directed flanges 48, the ilanges 40 and 42 being inter valve housing 2‘8 and the upper housing plate 46, and the upper edges of the flanges 72 and 74 of the lower valve housing 30 and the lower housing plate 66, „are each provided with a continuous channel 103. The channels 168 in the upper and lower valve housings 28 and 30 and in the upper and lower housing plates 46 and '66, are aligned, and adapted to receive an O-ring 110, which tightly ñts within the grooves 108 to provide a fluid tight The flanges 40 and 42 form side walls and an end wall 30 seal when the housing parts are brought together as shown in FIGS. 3 and 5. of the Valve housing, the other end Wall being formed by The upper surface of the upper valve housing 28, an upper housing plate 46 attached to the flange 44- by near the end flange 44, is bored to receive a pipe ñtting means of a plurality of cap screws 48 passing through 114, to which a flexible supply conduit 112, having a aligned holes in the plate 46 and flange 44, and holes in a Teilon gasket 45 positioned between the ilange and 35 valve 113 (FIG. 2), is connected. Referring to FIGS. l, 3, 5 and 6, the mold M com plate. The lower surface of the housing 28, in the area prises a cup-shaped outer shell 1,16 of steel, which is surrounding the bore 33, is ñnished ofi smoothly to pro lined with a refractory lining 118, extending to a point vide a valve seat Si), and is recessed to receive an O-ring short of the upper end of the shell, where it contacts the 52. A valve element 54 is slidably mounted within the 40 lower end of the boss 60. Refractory lining 118, in the operation of the process on titanium metal or alloy, may upper valve housing 28, the sides and one end of the be formed by heavily spraying the interior face of shell valve element having channels 56 adapted to engage longi '116 with a fine refractory material comprising from about tudinally extending ribs 58 on the side and end flanges 75-90% 1h02, 6-10% HfOz, 3-7% ZrO2 and 1-3% 48 and 42, which form guide means for the valve element. connected and their lower edges being even, The other end of the housing 28 is turned up to form a flange 44. The lower valve housing 3@ is generally rectangular in form, and includes, adjacent an end thereof, a down wardly extending boss 60, having a bore 62 therethrough. The other end of the housing has a downwardly extend ing ilange 64, which is adapted for connection with a housing plate 66, by means of plurality cap screws 70, which pass through aligned threaded holes in the end flange, the housing plate, and a gasket `68 of Teilon dis ‘[203. The upper end of the shell is flanged at 120, and the lower surface of the lower valve housing 30 is grooved to receive an O-ring 12,2 to form a seal between the valve housing and the flange 120. ‘Locking means are provided for selectively securing valve housings 28 and 30 together and to the shell 1116 of the mold. Thus, flange 120 is provided with four circumferentially spaced threaded bores to receive the posed between the flange and the housing plate. The valve housing 30 is provided with a pair of parallel side lower ends of threaded stud bolts 124. Lock nuts .126 Cludes a groove to receive an O-ring 94. vicinity of the pouring spout. are tightly screwed about the bolts against the flange flanges 72 and an end flange 74 (FIG. 4), which flanges 55 120 to prevent unscrewing of the stud bolts. Each stud bolt carries, in vertically spaced relation, a lower clamp are Icontinuous .With the upper edge or” the housing plate ing lever 128, held in proper position by upper and lower 66 to form four side walls of the valve housing, having lock nuts 130, and an upper clamping lever 132, held in an `open top for receiving a sliding valve element 78. place by a lower lock nut I134 and an upper wing nut The side and end flanges 72 and 74 have longitudinally extending ribs 76, which engage in longitudinally extend 60 §36. These levers are adapted to be swung into position over the upper edges of the flanged sides andthe ends ing side and end channels 80 (FIG. 3) in the valve ele of the valve housings 28 and "30, as shown in FIGS. l ment 78 to form a guiding means for the valve element. and 5, to clamp the valve housings and the mold in fluid An operating rod 82 is connected to the outer end of the -tight relation. valve element 78. This operating rod extends through an As shown in FIGS. 2, 3 and 4, the lower valve housing opening and a packing gland 84 in the lower housing 65 36 includes a pair of opposed passages i138 and 140, plate 66, and is provided on its outer end with a handle which enter the side flanges 72 in a horizontal direction 86 (FIG. l) by means of which the valve elements may and extend downward in an oblique direction through be operated. The upper surface of the valve element 78 the boss 62, terminating in the lower end of the boss as includes .a plurality of spaced, upwardly extending, dowels 88, which are adapted to engage an equal number of 70 shown in FIG. 3. The passages 138 and 140 are provided with fittings 141 and 142 to which flexible conduits 143 aligned recesses 90 in the lower surface of the upper valve element 54. The upper surface of the valve housing and 144, having valves 145 and 145a, are connected. These conduits may be readily disconnected so that the 30 surrounding the bore 62 is finished oil smoothly to mold and lower housing 30 can be removed from the provide a valve seat 92 for the valve element '78, and in 3,093,872 l e) Referring to FIG. l, the mold M is adapted to be re movingly litted within a mold receiving member MRM. This mold receiving member comprises a cup~shaped ele ment 146 of refractory material, in which is embedded a continuous copper tubular element 148 disposed adja cent the inner wall of the member 146. The copper tubular element 148 includes an inlet 150 and an outlet i152, extending outside the cup-shaped element 146, the Such preheating continues until the mold and the lining reach the desired temperature. The valve in the pouring spout C, adjacent the Crucible mentioned above and disclosed in application Serial No. 505,887, may then be opened to permit the discharge of the molten titanium or titanium alloy from the crucible, at a controlled discharge rate. When the valve in the pouring spout C is opened, the molten material, which in the case of titanium metal inlet 150 being adapted to be connected through a ñexible may be at a temperature in the order of 30010o `F., flows hose (not shown) with a source of cooling iiuid, which into the mold by force of gravity. `Because of the pre passes through a tubular element 148 and discharges :from the outlet 152. A pair of electrical conductors 154 are heated condition of the mold and the position of the connected to the inlet and outlet '158 and 152, respec outlet end 10 of the pouring spout C in close proximity tively. These conductors are adapted to be connected `to the bottom of the mold, the material flows into the to a source of high frequency, alternating current for 15 mold without splashing and substantially without thermal induction heating for a purpose to be described herein shock. rlïhe heating of the mold by means of the tubular after. element 148, as described above, continues during the The mold receiving member MRM is carried by a plat initial rfilling of the mold. Filling of the mold proceeds form P, comprising a base 156 provided with centering until a pool is collected at the bottom of the mold, where means 158 to receive the lower end of the cup-shaped 20 upon the fluid is admitted to the upper end and discharged element E146, in order to properly align the mold and the from the lower end of the hydraulic jack Hl' to lower upper and lower housings 23 and 30 during assembly the mold relative to the discharge end 10 of the connecting for a pouring operation as described below. The plat~ conduit. The rate of lowering of the mold can be regu form P is supported by a hydraulic jack HI, comprising lated by any known means. When the mold M contains a cylinder 16d, a reciprocating piston 162, and a piston 25 a substantial amount of the molten material, for example, rod 164 connected to the base 156 of the platform. The when it is one-uarter to one-half full, heating by lthe cylinder 168 includes upper and lower iluid connections tubular element 148 is discontinued and cooling of the A166 to receive and exhaust pressure fluid for raising and mold and molten material can be initiated by circulat lowering the platform and the mold M supported thereon. ing a cooling liuid, such as air or liquid, through the The operation is as follows: 30 tubular element 14S to bring about uniform solidifica It may -first be assumed that it is desired to íill the tion. As vfilling of 4the mold continues, the mold M and mold M with molten material from the crucible, not the connecting member CM are lowered until the outer shown, by way of the pouring spout C. The clamps 128 ilange 38 of the stop collar 18 engages the rabbet 36 in and 132 are set, as shown in FIG. l, to securely fasten the lower end of boss 32, which is effective to limit the the connecting member CM to the mold and the valve 35 downward movement of the mold ‘and the connecting housings 28 and 38 together. The valve elements 54 member. The molten material in the mold is preferably and 78 are moved to their open position, as shown in kept under a constant inert gas pressure until it has solidi FIG. 5, by pulling the handle 86 outwardly until the fied and cooled. In the case of titanium, inert gas pres outer ends of the valve elements are stopped by striking the housing plates 46 and 66. The dowels 88 in the lower 40 sure should be maintained until a temperature 800° F. has been reached. valve elements 78 are in engagement with the recesses 98 If desired, -the valve 145g -in the conduit 144- which is in the upper valve element 54, so that the two valves are connected with the source of vacuum can be closed dur compelled to move together. When the valves are in ing pouring, or the valve can be partially closed so that their open position, as shown in FIG. 5, the mold `M and platform P are raised by admitting pressure fluid to 45 there is a continuous supply of linert gas by way of the conduit 112 and conduit 144 which is at a rate sufficient the space below the piston 162 and exhausting fluid from -to maintain the desired pressure within the parts. This the space above the piston. As the pouring spout C is mode of operation has the advantage of permitting the fixed against movement, and in view of the sliding con relatively cool supply of »insert gas admitted by conduit nection between the boss 32 on the upper valve housing 112 to pass over and about the valve elements 54 and 28 and the outlet end 10 of the connecting conduit C, 78, and about the cam locks 98, to protect them from the mold M and the connecting member CM are moved the high temperature of the molten material. Prefer upwardly relative to the outlet end 1t) of the spout C ably, the pressure is kept slightly above atmospheric until the lower or outlet end 16 is disposed slightly above and is maintained at a constant value during the pouring. the bottom of the mold in the position shown in HG. l. When the mold M is filled, the' valve in the pouring Flexible conduit I144 is connected with an exhaust pump 55 spout C at the Crucible may be closed, and the valve ele or other source of Vacuum, while the other conduit 1435` ments 54 and 76 may be moved toward their closed posi is connected with a supply of inert gas under pressure, tion by pushing on the handle 86 until the nibs 58 and 76 such as helium, for example. At the same time the con engage the channels 56 yand 80 in the ends of the sliding duit i112 to valve housing 26 is connected with the com valve members. The cranks 104 may then be oscillated mon supply of inert gas. After the mold and valve as~ 60 from the position shown in solid lines in FIG. 2 to sembly have been evacuated through line 144», valve 145a being open, inert gas is admitted to the valve hous ings and mold by opening valves 113 and 145. As a result of this operation, the interior of the mold, the interior of the position shown in dotted lines, which oscillates the eccentrically mounted cam locks 98 to forcibly urge the valve members 54 and 78 against their valve seats 50` and 92, respectively, providing a fluid tight seal between the the pouring spout C, and the interior of the connecting 65 valve elements and the discharge end 10 of the pouring member CM, are flushed of contaminating gases and are spout on one hand, and the open top of the mold M on the iilled with an inert atmosphere of helium at a relatively other hand, and at the same time locking the valve elelow gage pressure, which assures the continued exclusion ments against inadvertent opening movement. The mold of any other gas that may react with the molten mate 70 M may then be removed by separating the valve housings rial to be delivered into the mold. 28 and 30 so that the upper Áhousing 28 remains with the Meanwhile, the mold M is inductively preheated to a pouring spout C and the lower housing 3d is removed temperature in the neighborhood of 1260*’ lto l300° F. with the mold. To facilitate such separation, the wing by passing a high frequency alternating current through nuts 136 may be loosened or removed, which enable the tubular element 148 by means of the conductors 154. 75 the upper clamping levers 132 to be swung out of the @,osasve 8 «way of the upper housing 23, or removed, as shown in said discharge opening and the lower valve housing being FIG. 6. The valves 113, 145 and 145e are closed, and adapted to remain with the mold with its valve closing said open top. the piston 162 in the hydraulic jack HJ may then be lowered, whereby the upper and lower valve housings 2. The apparatus of claim l including means to move >28 and 30 are separated, as shown in FIG. 6. "ihe mold 5 the mold and associated valve housings axially relative to said conduit to vary the distance between the discharge M may be removed -and when the ingot has reached a opening of said conduit yand the bottom of said mold. temperature below reactive temperature, lower valve 3. The apparatus of claim 1 including a member for `housing 39 can be removed for placement on another receiving said mold, said member including a tubular mold for repeated operation. lf desired, a number oi lower valve housings can be provided to speed up the 10 element in heat exchange relation to said mold, and process. The mold may be left Within the mold receiv» `ing member MRM for any desired length of time, where it may be cooled at a selected rate by the external cool means to supply a heat exchange Huid to said tubular element. 4. The apparatus of claim 3 in which said tubular ele ment is of electrically-conductive material, »and means and controlled cooling rate beneiicially iniiuence proper 15 for `connecting Asaid `tubular element to a source of high ing means. Both the presence of inert gas under pressure >.crystal structure in the product ingot. frequency alternating current. 5. The apparatus of claim l including means to supply »an inert atmosphere within said mold and to withdraw gases lfrom said mold. -on the platform P, and the hydraulic jack Hl is operated 6. The apparatus of cla-im 5 in which the supply means to raise the platform. The centering means 158 assures 20 for inert atmosphere includes a passageway through one ‘that the mold is properly aligned with the connecting of said valve housings. yconduit C, and the valve elements 54 and ’73, being locked 7. The apparatus of claim il including cooperating -by means of the cam locks 98, assure that the dowels means carried by said conduit and said upper valve ’S8 enter the recesses 90 land that the housings ZS and Vit) are brought together in proper relationship so that the 25 housing to limit relative sliding movement of said hou-sing with respect to said `conduit so as to prevent removal of O-ring 21.10` is properly received within the grooves 108 said upper »valve housing from said conduit. `in the upper and lower housings. When the parts are 8. The apparatus of claim 7 wherein said means carried lso brought together, the clamping levers 132 may then by said conduit >and upper valve housing to lim-it rela again be brought to bear against the upper surface of »the upper housing 28 and tightened by means of the 30 tive sliding movement of said housing with respect to said conduit comprise a flange on said conduit adjacent said .Wing nuts 136. The valves in the conduits 112, 142 and discharge opening and a shoulder vvithin the bore of said 144 may then be opened, and the valve members 54 and upper valve housing above its associated valve member 70 opened by drawing on the handle 86, as described for engagement with said iiange. iabove. 35 9. The apparatus of claim l «wherein each valve hous~ It will be understood that various changes may be ing includes a valve sea-t, said valve members are slidable made in details of construction yand in the arrangement over their respective seats and said valve housings each yof parts of the system disclosed herein without depart Y include locking means lfor forceably urging their respec 'ing from the principles of the invention and the scope of tive valve members against their respective seats to seal the annexed claims. For example, the ingot mold may end of the conduit and the mold, respectively after a itself be provided with a suitable temperature control 40 the casting operation. >means, and other modifications generally as described ’10. The apparatus of claim 9 including means within When it is desired to form »another ingot, the mold M and the mold receiving member MRM are mounted Yand shown in copending application Serial No. 505,887 may be employed. said valve housings interconnecting said valve members for concurrent transverse sliding movement over their I claim: 45 respective seats, said interconnecting means being separa~ l. An apparatus `for casting an ingot of molten mate ble upon movement of said valve members in a direc rial, comprising: an ingot mold having an open top; a tion normal to said transverse sliding movement. downwardly-directed conduit for delivering said molten ’11. A separable valve assembly `for, providing »a gas material into said mold, said conduit having a discharge _ tight connection between a supply conduit and a mold opening at its iower end and being receivable through 00 during a casting operation, comprising: an upper valve the open .top of said mold to position said discharge housing having `a bore adapted to receive said supply `opening within the mold; a connecting member connect conduit, the upper portion of said bore being of reduced »ing said mold and conduit in gas~tight relation, sald con diameter to provide a close sliding tit with the outer pe uecting member comprising an upper valve housing hav riphery of said conduit and having sealing means adapt ,ing a bore slidably receiving -said conduit; se-aling means 55 ed to provide a gas-tight but slidable connection with said providing `a gas-tight sliding ñt between said bore and the supply conduit; a lower valve housing having a gas-tight Vouter periphery of said conduit; a lower valve housing hav but separable connect-ion with said upper valve housing ing a gas-tight but separable connection with said upper and having a bore registering with the bore of said upper valve housing and having a bore registering with the bore valve housing and also adapted to receive said supply of the upper vaive housing and also adapted to receive 60 conduit, said lower valve housing being adapted to be :said conduit, said lower valve housing being tixed to said secured in fixed gas~tight relation to the top of said mold; mold; a pair of slide valve members, one slide valve a pair of slide valve members, one of said valve members member being carried by each valve housing and each being carried by each val-ve housing and each valve mem valve member being movable between open and closed ber being movable between open and closed positions positions opening and closing the bore of its respective opening and closing the bore of its respective housing; housing; means for moving said valve members between each valve housing having a valve seat receiving its re said open and closed positions; said ingot mold and valve spect-ive valve member in said closed position; means for khousings being movable axially with respect to said con moving said valve members :between said open and closed duit lto position said discharge opening at selected dis tances trom the bottom of the mold during a mold-tilling 70 positions; means carried by each valve housing to force ably urge yand lock each valve member against its seat, operation and within the upper valve housing above said said valve housings being separable together with their re valve members at the end of -a mold-ñl-ling operation, said val-ve housings being separable together with their respec tive valve members, the upper valve housing being adapt spective valve members with the upper valve ‘housing be ing adapted to remain with said supply conduit with its ed to remain with said CGnduit with its valve closing 75 valve closing the end thereof and the lower valve housing 3,093,872 gage a recess in the other valve member.