Process for removal of siliceous cores from castings
Abstract
Abstract PROCESS FOR THE REMOVAL OF A SILICEOUS CORE FROM A METAL CASTING WHICH INVOLVES PLACING THE CASTING IN A CLOSED VESSEL, INTRODUCING AN AQUEOUS CAUSTIC ALKALI SOLUTION INTO THE VESSEL CAPABLE OF DISSOLVING THE CORE, HEATING THE ALKALI SOLUTION TO A TEMPERATURE FOR MAXIMUM RATEOF REMOVAL BUT NOT HIGH ENOUGH TO ATTACK THE CASTING, THEREAFTER REDUCING THE PRESSURE TO INDUCE BOILING OF THE SOLVENT MATERIAL TRAPPED IN THE PASSAGES IN WHICH THE CORE HAS BEEN PARTIALLY DISSOLVED BY THE SOLUTION, AND REPRESSURIZING THE VESSEL, AND THEN REPEATING THE STEPS OF REDUCING AND INCREASING THE AMBIENT PRESSURE UNTIL THE CORE IS COMPLETELY DISSOLVED FROM THE CASTING, THE INDUCED BOILING AND RECONDENSATION SERVING TO REMOVE AND REPLACE SPENT LEACHING SOLUTION IN THE SMALL CORED PASSAGES.
Inventors
- 👤 Charles M Hammond
- 👤 Ronald D Markle
- 👤 Robert E Mccracken
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
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