Document mpOVqL7rJ5BGY52Xv8e7oK7e0

INGOTS For im* tact FOSECO 0123 / THE' FQ5EC0 "PROFAX" TUP OR FOUR PIECE SLA9 ASSEMBLY FDR USE IN SLAB TYPE SQUARE AMD RECTANGULAR BIG-ENDDCLiftJ HOLDS. Daring the past feu years important changes have taken place in re quirements for flat rolled products and plate products. Larger ingots have Peen mode to meet the demands of consumers for larger coils of aluminum killed deep drauing steel. At the same time consumers of plate product have found the economics and the metallurgy of big end down molds accept able. Dna of the major factors aiding these changes uas the introduction * of Foseco's "Feedex" exothermic tuo side hot top. As pioneer of the exothermic hot top, Foseco, Inc., continually search for improved methods of hot topping. Early in 1963, Foseco, Inc. sau the advantages that the "Profax" hot top uould have' over the exothermic hot top. Some of the advantages of the "Profax" hot top have been listed. The following is a more detail ed explanation of the use and the benefits to be derived from the use of the "Profax" hot top on slab type ingots. The fact that a 3/4 inch thickness of refractory insulating material can produce sound ingots of high quality is the characteristic of "Profax". The low density of "Profax" has made possible simple, compact packaging and storage. A typical example is the "Profax" hot top for a 30" x 65" mold. A 42" x 60" pallet holds 60 hot tops; a truckload uill hold 480 hot tops and when shipped tuo pallets high, 360 hot topB can be shipped per truckload. By stacking the pallets tuo.high, 120 hot tops C3n be stored in an area 42" x 60". Note Figure 9. Registered Trade Hark. FOSECO 0124 Figure 9 Compact shipping and storing of "Profax" hot tops. Each pallet contains 60 hot tops for a 30" x 65" mold. Pallets arB stacked tuo high uith ease and safety. 120 hot tops can be stored in an are3 <42" X 60". Because of the small space required for a large number of hot tops and their ease of installation, the "Profax" hot top can be put into the mold at the pouring platform if desired. The rapidity of installation is such that the pouring platform is not tied up for any great length of time. Twenty f the 30" x 65" "Profax" tops can be set by tuo men in about 30 minutes uithout the use of a crane. Note figures 10 through 1<4. 0V15 fOS^c / Figure ID First step in the in stallation of "Profax" hot tops in a 25" x 59" big-end-down mold. Sectiona of oxygen lonca are put through the hangers so as to carry and also to sus pend the hot top in position in the mold. Easily inserted hangers are made of varying lengths eo as to locate hat top at desired depth in mold. Note one man is able to Basily carry the entire hot top which weights 55 pounds. Figure 11 Locating "Profax" hot top slabs agsinst mold walls. In shops where rig id safety precau tions are taken, a light weight walk is placed between the molds for added saf ety. FOSECO 0126 J Figure 12 Putting spring clips in place - the clips hold the hat top firmly bgainst mold wall to pre vent metal penetration behind the hot top and also assures that the top can not float out of mold during pouring. It'a imperative to have clean mold walls so that the "Profax" fits tight ly against the mold wall. Where "Profax" is used regularly on a particu lar mold, the hot top area is kept clean by the "Profax" top itself and this area of the mold does not naed any mechanical cleaning be tween heats. Figure 13 The last step in the "Profax" hot top preparation is to remove the lifting or suspending rods; since the rods are not needed during tracking or pouring, they are saved and used over again. The hot top is neld so firmly in place by the spring clips that they can be tracked over the roughest of tracks without disturbing or harming the "Profax" hot top. FOSECO 0127 / Figure 14 Fully assembled "Profax" 2-slab hot top ready for use. Care must be taken to assure that the spring clips are making tight contact at the bottom of the pads so as to hold the "Profax" pads firmly against the mold wall. The installation of the "Profax" hot top is clean; the surfaces of the "Profax" are hard and not friabls, and, as a result, no foreign debris falls into the mold during installation. The cleanliness of the "Profax" is such that no vacuuming of the mold is necessary after assembly; this is an im portant advantage uhen putting hot tops in place at the pouring platform. The strength and rigidity of the finished hot top assembly is such that the molds can be tracked without damaging or altering the position of the hot tops in the molds. The "Profax" hot top can be set at varying heights in the mold to give a predetermined ingot weight. FOSECO 0128 As soon as the hot top is filled, Foseco "Ferrux 1D7" Is added on top of the hot top metal to provide the necessary insulation. "Ferrux 107" has bean especially compounded for use with "Profax" hot tops and no other topping com pound has been found that will produce as consistent results cf high yields of segregation free steel. The importance of following a prescribed hot top covering practice cannot be over-emphasized. The proper amount of "Ferrux 107" and its method of addition is recommended by Foseco and for optimum re sults this practice should be followed. Note Figure 16 and 17. Adding "Ferrux 107" top covering to the filled hot top - the addition is mads os soon as possibla after the hot top is full so as to prevent heat loss. A carefully followed top covering practice outlined by Foseco engineers must bs adhered to for maximum results. FOSECO 0129 t In auch instances a special type spring clip is used to hold the top in place. An important advantage of the "Profax" hot top is the fact that the ingot and the hot top can be filled uith a full stream and no shut-off or slow-down of the stream is necessary. Because of its tapered bottom edgs which is characteristic to "Profax", thers Is practically no up-thrust from the rising metal. This eliminates entrappment of slag and Inclusions as so often happens when conventional thick hat tops are used. Because of the few er number of shut-offs per heat there is less chance of having a leaking or running stopper; but, even in the case of a full running stopper, no damage is caused to the ingot. Note Figure 15. Figure.15 "Profax" hot tops are poured straight up uith a full stream with out halt or slowdown until the hot top is full - this cuts down on the number of shut-offs per heat and helps prevent leaking or running stoppers. FOSECO 0130 Figure 17 "Profax" hot topped ingots after the hot topping process is complete. In this case, "Profax" boards mere put on top of an exothermic topp ing compound cover. Until the development of "Ferrux 107", this was the only method to obtain maximum results with "Profax" hot topping. The use of "Ferrux 107" assures maximum results and also is less cost ly than the duplex top covering method as shown. "Prufax" hot topped ingots can be moved immediately after pouring if tha pouring bay is needed for another heat. The timing of the move is important as delaying it too long will cause ingot pattern with "Profax" hot top use just as with any other hot topping method. The ingots should be moved care fully to prevent metal spillage. Even though the "Ferrux 107" top cover crust may be broken by the move, it will weld together again and provide excellent insulation. At stripping, the "Profax" hot top leaves very little debris. A large portion of the "Profax" hot top is consumed during the solidification period and only a small amount of light weight powder remains that falls easily from the hot top area at stripping. There is "less clean-up at the stripper with "Profax" than from any other hot top and there ie little or no carry-over of refractory into the soaking pit. Note Figure 18. FOSECO 0V31 ; Figure 18 "Prcfax" hot topped ingot after stripping. "Profax" has strip ped completely free of the hot top metal with very little debris present. Mote the very slight shoulder on the ingot and the ab sence of hot top material at the junction between the hot top and the body of ingot, and also the very flat feed produced by the "Profax" hot topping method. The practically shoulderless "Profax" ingot provides many advantages to the rolling mill operator. During rolling, the small shoulder disappears without any roll-over after a couple of passes through the mill. The slab has all the appearances of an opan-topped ingot on the surface. Because there is no adhering refractory there is no flying debris. There are no rolled-in surface inclusions from the "Profax" hot top and it is impossible to tell by visual inspection where the hot top junction was located except in rare instances when light metal flashing gets behind the "Profax" whBn dirty molds are used. Even in the case where some metal flashing is rolled into the surface Df the ingot, the scab can easily be removed by hot scarfing as it contains no refractory. Bee Figure 19 and 2D. FOSECO 0132 ! Figure 19 Slab produced from ingot made mith a convention al hot top. Note ovBrroll of hot top Junction end poor side surfaoe even below the hot top Junction. Top discard from this slab was over 7 feet long. Figure 2D Slab produced from same type ingot as that shown in Figure 19 but using "Profax" hot top. Note good surface and absence of hot top Joint demarc ation. Sound product was made with a top cut cf only feet. The sur face in the head metal area is as good as that of the body of the ingot. / FOSECO 0133 The steelmaker should metallurgically study the head metal of the "Profax" topped ingots. This head metal is as clean and as free of segregates as the body of the ingot. Except for about 3^ top discard, the head metal is superior to much of the metal in the center third of a conventionally topped ingot. Head metal can nou be used as prims product uith much higher yields because: 1.) There is no defective hot top Junction metal due to rolled-in inclusions or scabs 2.) The head metal is metallurgically sound. Dost users of "Profax" take advantage of this. See Figures 21 through 24. Figure 21 Longitudinal macro-etch through the hot top portion of a 24" uide big-end-doun ingot hot topped uith "Profax", .45 carbon steel. Mote absence of both carbon and non-metallics segregation. FOSECO 0134 / Figure 2k Transverse macro-etch sections taken from the center of top discards of slabs of aluminum killed deep drawing steel made in 29 x 56 x 85 ingots using "Pro fax" hat tops. In every case the steel is sound at the B5% ingot level and al so up to the 9k% ingot level. With well controlled "Profax" hot topping prac tice a total of 7% top discard will assure sound metallurgically acceptable high quality steel. FOSECO 0135 i THE FQSECO "PROFAX" TUD OR FOUR PIECE SLAB ASSEFIBLY FOR USE IN SLAB TYPE SOUARE AND RECTANGULAR BIG-ENDDOlilN KOLOS. FOSECO 0136 ;