Study On Technological Adaptability Of Reclaimed Sand Of Clay Sand Containing Different Core Sand

China is the biggest casting producer in the word. The production of Casting reached more than 39.6m tons in 2010, approximately 60% of casting production used for clay sand process, a lot of used clay sand is scrapped every year. This is not only a waste of natural resources, but also pose great risk to the environment. Therefore, to take the used clay sand recycle completely is an essential measure for protecting the environment and natural resources, and has fundamental significance to the foundry industry in sustainable development.On the basis of depth understanding of domestic and foreign clay sand reclamation technology development status,the issue through a combination method of theoretical analysis and experimental research, combined the early research resultscore of clay sand containing core sand regeneration and recycled sand used for he same system of core sand process, researched the process performance of clay recycled sand containing core sand used to the changed system of core sand process, determine the adaptability of the reclaimed sand to the changed system core sand process, and modification of the clay reclaimed sand and improvement of casting process performance of recycled sand which mixed coated sand was investigated experimentally.According to the research, when the sodium silicate sand is prepared with reclaimed sand containing sea coal and furans self-hardening resin sand, the highest strength is 1.11Mpa; when the Hot-box sand is prepared with reclaimed sand, the highest thermal state tensile strength is 0.89Mpa, the highest room temperature tensile strength is 1.51 Mpa and it can meet the needs of the foundry production. However, the cold-box sand and coated sand prepared with reclaimed sand can not meet the needs of the foundry production.Furan self-hardening resin sand, hot-box sand, cold-box sand, coated sand prepared with reclaimed sand of clay sand containing sea coal and sodium silicate sand can’t meet the needs of casting production.The strength of sodium silicate sand prepared with reclaimed sand of clay sand containing hot-box sand is closed to the new sand, the strength of cold-box sand and coated sand prepared with reclaimed sand approach or reach 80% of the strength of molding sand prepared with the new sand, meet the needs of casting production, the highest strength of furan self-hardening resin sand prepared with reclaimed sand is 0.08Mpa, can’t meet the needs of casting production.The strength of sodium silicate sand prepared with reclaimed sand of clay sand containing cold-box sand approach the strength of molding sand prepared with the new sand, the strength of hot-box sand and coated sand prepared with reclaimed sand reach or exceed 80% of the strength of molding sand prepared with the new sand, can meet the needs of casting production, the highest strength of furan self-hardening resin sand prepared with reclaimed sand is 0.14Mpa, can’t meet the needs of casting production.The strength of sodium silicate sand prepared with reclaimed sand of clay sand containing coated sand is more than 1Mpa, the highest thermal state tensile strength of hot-box sand prepared with reclaimed sand is 0.66Mpa, the highest room temperature tensile strength is 1.12 Mpa, the highest real-time tensile strength of cold-box sand prepared with reclaimed sand is 1.02Mpa, the highest 1h tensile strength is 1.21 Mpa, can meet general needs of coremaking, the highest strength of furan self-hardening resin sand prepared with reclaimed sand is only 0.05Mpa, can’t meet the needs of casting production.After second calcination of 800℃,10min the performance of clay regeneration sand has not improved significantly, the strength of coated sand prepared with it is slightly higher than the strength of coated sand prepared with the untreated clay reclaimed sand, but still lower than the strength of the coated sand prepared with new sand.Joining oxalic acid solution of 3% of the sand quality and the concentration of 0.01% in the coated sand prepared with clay reclaimed sand can be able to a certain extent improve the strength of the coated sand prepared with clay reclaimed sand, however, when adding excessive oxalic acid solution excessive, the strength is seriously reduced.After joining silane coupling agent of 1.5% of the total resin quality, the thermal tensile strength of the coated sand increase by 31%, the room temperature tensile strength increase by 25.4%, but still lower than the strength of the coated sand prepared with new sand.The strength of coated sand after joining the oxalic acid solution and the silane coupling agent is lower than the strength of coated sand after joining silane coupling agent, after joining oxalic acid solutionn of 3% of the sand quality, concentration of 0.01% and the silane coupling agent accounted for 1.5% of the resin quality, the hot tensile strength increase by 6.9%, the room temperature tensile strength increase by 12.3%.