Contour mold casting method

Abstract

The present invention provides a casting method comprising the steps of obtaining a thermal distribution of mold sand for a casting, and determining a mold wall thickness profile based at least partially on the mold sand thermal distribution.

The invention is claimed as follows:  
     
         1 . A casting method comprising the steps of: 
 obtaining a thermal distribution of mold sand for a casting; and    determining a mold wall thickness profile based at least partially on the mold sand thermal distribution.    
     
     
         2 . The method of  claim 1  further comprising the step of obtaining a stress distribution of the mold sand for the casting, and the step of determining a mold thickness profile further includes determining the mold wall thickness profile based at least partially on the mold sand stress distribution.  
     
     
         3 . The method of  claim 1  further comprising the step of fabricating a mold having the determined mold thickness profile.  
     
     
         4 . The method of  claim 3  wherein the step of fabricating a mold includes fabricating a cope mold and a drag mold, the cope mold having a cope mold wall thickness profile, the drag mold having a drag mold wall thickness profile, and joining the cope mold and drag mold to form a cavity.  
     
     
         5 . The method of  claim 4  wherein the step of fabricating the cope mold includes a top cope mold pattern box and a bottom cope mold pattern box, the bottom cope mold pattern box containing a pattern for shaping the casting, and the top cope mold pattern box containing a pattern having the cope mold wall thickness profile.  
     
     
         6 . The method of  claim 5  wherein the top cope mold pattern box has at least one blow tube opening.  
     
     
         7 . The method of  claim 6  wherein the at least one blow tube opening accommodates at least one tamper pin, the tamper pin being hollow and having an opening and a tip vent.  
     
     
         8 . The method of  claim 5  wherein the top cope mold pattern box and bottom cope mold pattern box are joined to form a cavity.  
     
     
         9 . The method of  claim 8  further comprising the step of blowing sand into the cavity formed by joining the top cope mold pattern box and the bottom cope mold pattern box.  
     
     
         10 . The method of  claim 9  further comprising the step of venting curing gas into the sand in the cavity formed by joining the top cope mold pattern box and the bottom cope mold pattern box.  
     
     
         11 . The method of  claim 9  further comprising the step of separating the top cope mold pattern box and the bottom cope mold pattern box.  
     
     
         12 . The method of  claim 4  wherein the step of fabricating the drag mold includes a top drag mold pattern box and a bottom drag mold pattern box, the bottom drag mold pattern box containing a pattern for shaping the casting, and the top drag mold pattern box containing a pattern having the drag mold wall thickness profile.  
     
     
         13 . The method of  claim 12  wherein the top drag mold pattern box has at least one blow tube opening.  
     
     
         14 . The method of  claim 13  wherein the at least one blow tube opening accommodates at least one tamper pin, the tamper pin being hollow and having an opening and a tip vent.  
     
     
         15 . The method of  claim 12  wherein the top drag mold pattern box and bottom drag mold pattern box are joined to form a cavity.  
     
     
         16 . The method of  claim 15  further comprising the step of blowing sand into the cavity formed by joining the top drag mold pattern box and the bottom drag mold pattern box.  
     
     
         17 . The method of  claim 16  further comprising the step of venting curing gas into the sand in the cavity formed by joining the top drag mold pattern box and the bottom drag mold pattern box.  
     
     
         18 . The method of  claim 12  further comprising the step of separating the top drag mold pattern box and the bottom drag mold pattern box.  
     
     
         19 . A method of fabricating a mold for making a casting comprising the step of fabricating a cope mold and a drag mold, the cope mold having a cope mold wall thickness profile, the drag mold having a drag mold wall thickness profile, and joining the cope mold and drag mold to form a cavity.  
     
     
         20 . The method of  claim 19  wherein the step of fabricating the cope mold includes a top cope mold pattern box and a bottom cope mold pattern box, the bottom cope mold pattern box containing a pattern for shaping the casting, and the top cope mold pattern box containing a pattern having the cope mold wall thickness profile.  
     
     
         21 . The method of  claim 20  wherein the top cope mold pattern box has at least one blow tube opening.  
     
     
         22 . The method of  claim 21  wherein the at least one blow tube opening accommodates at least one tamper pin, the tamper pin being hollow and having an opening and a tip vent.  
     
     
         23 . The method of  claim 20  wherein the top cope mold pattern box and bottom cope mold pattern box are joined to form a cavity.  
     
     
         24 . The method of  claim 23  further comprising the step of blowing sand into the cavity formed by joining the top cope mold pattern box and the bottom cope mold pattern box.  
     
     
         25 . The method of  claim 24  further comprising the step of venting curing gas into the sand in the cavity formed by joining the top cope mold pattern box and the bottom cope mold pattern box.  
     
     
         26 . The method of  claim 25  further comprising the step of separating the top cope mold pattern box and the bottom cope mold pattern box.  
     
     
         27 . The method of  claim 19  wherein the step of fabricating the drag mold includes a top drag mold pattern box and a bottom drag mold pattern box, the bottom drag mold pattern box containing a pattern for shaping the casting, and the top drag mold pattern box containing a pattern having the drag mold wall thickness profile.  
     
     
         28 . The method of  claim 27  wherein the top drag mold pattern box includes at least one blow tube opening.  
     
     
         29 . The method of  claim 28  wherein the at least one blow tube opening accommodates at least one tamper pin, the tamper pin being hollow and having and opening and a tip vent.  
     
     
         30 . The method of  claim 27  wherein the top drag mold pattern box and bottom drag mold pattern box are joined to form a cavity.  
     
     
         31 . The method of  claim 30  further comprising the step of blowing sand into the cavity formed by joining the top drag mold pattern box and the bottom drag mold pattern box.  
     
     
         32 . The method of  claim 31  further comprising the step of venting curing gas into the sand in the cavity formed by joining the top drag mold pattern box and the bottom drag mold pattern box.  
     
     
         33 . The method of  claim 32  further comprising the step of separating the top drag mold pattern box and the bottom drag mold pattern box.  
     
     
         34 . A method for casting a metal product comprising the steps of: 
 pouring molten metal into a mold, the mold including mold sand having a binder, the mold having a cavity in the mold sand to receive the molten metal; and    providing the mold with a mold wall thickness profile sufficient to maintain mold sand binder integrity at least until the molten metal forms an outer skin.    
     
     
         35 . A method for casting a metal product comprising the steps of: 
 fabricating a mold from mold sand, the mold having a mold wall thickness profile;    pouring molten metal into the mold; and    cooling the molten metal.    
     
     
         36 . The method of  claim 35 , wherein the mold wall thickness profile is optimized to thermally reclaim the mold sand.  
     
     
         37 . A mold for making a metal casting, the mold comprising a mold wall thickness profile.  
     
     
         38 . The mold of  claim 37  wherein the mold wall thickness profile includes a cope mold wall thickness profile and a drag mold wall thickness profile.  
     
     
         39 . The mold of  claim 37  wherein the mold wall thickness profile is comprised of mold sand, the mold sand including a binder, the binder having a strength, and wherein the mold wall thickness profile is optimized to maintain mold sand binder strength at least until the molten metal forms an outer skin.  
     
     
         40 . The method of  claim 35  wherein the mold is made of mold sand, the mold sand including a binder, and during the step of cooling the molten metal the mold sand binder reaches a break down temperature.  
     
     
         41 . The method of  claim 40  wherein at least 70% of the mold sand binder reaches a break down temperature.