Method and apparatus for evaluating the flowability of core forming materials
View Patent ↗A method and apparatus for evaluating the flowability of a core-forming material in which an airborne core-forming material is blown downwardly into a first, downwardly extending, long and confining passageway for a predetermined time, and the airborne core-forming material is allowed to escape the first long, confining passageway by diverting it into a short, transverse passageway, and further diverting it into a second, upwardly extending confining passageway, and the flowability of the core-forming material is evaluated from the quantity of core-forming material that has entered the second, upwardly extending confining passageway.
1. A method of evaluating the flowability of a core-forming material comprising the steps of:
providing a test fixture forming a pair of substantially parallel core-forming passages several inches long and joined adjacent their one ends by a transverse passageway, with vent openings at their one ends and with an inlet opening at the other end of a first one of the core-forming passageways for admission of core-forming material;
blowing the core-forming material into the inlet opening until the first one core-forming passageway is filled;
curing the core-forming material in the test fixture;
opening the test fixture and removing the cured core-forming material; and
evaluating the flowability of the core-forming material from the quantity of core-forming material that has entered the second one of the pair of substantially parallel core-forming passageways.
2. The method of claim 1 , wherein the pair of substantially parallel core-forming passageways have a cross-sectional area of about 1 square inch, and the transverse passageway has a cross-sectional area of about 1.15 square inches and a length of about 0.50 inches.
3. The method of claim 2 , wherein the pair of substantially parallel core-forming passageways each have a square cross-section that is about 1 inch by 1 inch and wherein the transverse passageway has a rectangular cross-section about 1 5/16 inch by about ⅞ inch.
4. The method of claim 2 , wherein each of the substantially parallel core-forming passageways is about 8 inches long.
5. The method of claim 1 , wherein a flowability number is determined by weighing the total quantity of cured core-forming material that has been removed from the test fixture, cutting the cured core-forming material that has been removed from the test fixture to produce a sample including only cured core-forming material that has entered the second one of the pair of substantially parallel core-forming passageways, weighing the sample of the cured, core-forming material that has entered the second one of the pair of substantially parallel passageways, and dividing the weight of the sample of cured, core-forming materials that has entered the second one of the pair of substantially parallel passageways by the weight of the total quantity of cured, core-forming material that has been removed from the test fixture.
6. The method of claim 5 , wherein different core-forming materials are used and the flowability numbers of the different core-forming materials are recorded for comparison and future use and for comparison with the actual performance of the different core-forming materials in production.
7. An apparatus for testing the flowability of mixtures for forming cores for castings comprising a metal test fixture forming a pair of substantially parallel core-forming passages joined adjacent their one ends by a transverse passageway, and including vent openings at their one ends, an inlet for core-forming materials at the other end of one of the substantially parallel core-forming passages, and means for admitting a flow of airborne core-forming material in the inlet opening at the other end of the one of the substantially parallel core-forming passageways.
8. The apparatus of claim 7 , wherein the core-forming passageways have a square cross-section one inch by one inch and a length of eight inches.
9. The apparatus of claim 8 , wherein the transverse passageway has a length of ½ inch and a cross-sectional area of 1.15 square inches.
10. The apparatus of claim 7 , wherein the means for admitting a flow of airborne core-forming material into the metal test fixture comprises the same means used in producing cores in production.
11. The apparatus of claim 7 , wherein each of the pair of substantially parallel core-forming passageways has a cross-sectional area of about 1 square inch and the transverse passageway has a cross-sectional area of about 1.15 square inches.
12. A method of evaluating the flowability of a core-forming material comprising the steps of:
blowing an airborne core-forming material downwardly into a first, downwardly extending, long, confining passageway for a predetermined time;
allowing the airborne core-forming material to escape the first long, confining passageway by diverting it into a short, transverse passageway, and further diverting it into a second, upwardly extending, confining passageway; and
evaluating the flowability of the core-forming material from the quantity of core-forming material that has entered the second, upwardly extending, confining passageway.
13. The method of claim 12 , wherein the first, downwardly extending, long, confining passageway and second, upwardly extending, confining passageway have a cross-sectional area of about one square inch, and the short transverse passage has a cross-sectional area of about 1.15 square inches and a length of about 0.50 inches.
14. The method of claim 13 , wherein the first and second long confining passageways each have a square cross-section that is about one inch by about one inch and the short transverse passageway has a rectangular cross-section about 1 5/16 inches by about ⅞ inch.
15. The method of claim 12 , wherein the long confining passageways are each about eight inches long.
16. The method of claim 12 , wherein a flowability number is determined by weighing the total quantity of core-forming material that has been received within the first and second long confining passageways and the short transverse passageway, weighing the quantity of the core-forming material that has entered only the second long confining passageway, and dividing the weight of the quantity of cured core-forming material that has entered only the second long confining passageway by the weight of the total quantity of cured core-forming material that has entered the first and second long confining passageways and the short transverse passageway.
17. The method of claim 16 , wherein different core-forming materials are used and the flowability numbers of the different core-forming materials are recorded for comparison and future use and for comparison with the actual performance of the different core-forming materials in production.