Influences of frequency,amplitude,vibrating time,moisture in sand,thickness of sand layer and pretreatment of high frequency vibration and heating on sand reclamation were studied.Cured binder layers around sand grain...Influences of frequency,amplitude,vibrating time,moisture in sand,thickness of sand layer and pretreatment of high frequency vibration and heating on sand reclamation were studied.Cured binder layers around sand grains are completely removed and original sand grains remain unbroken by vibration at a certain frequency and amplitude.Effectiveness of sand reclamation by the vibration method is correlated to the vibration force which depends on the combination of frequency and amplitude to a great extent.The optimum vibration condition is limited by the capacity of vibrator.Drying of used sand is required.The thickness of used sand is an important factor.Pretreatments of used sand are also required.Moreover,preheating in a certain temperature range is preferable to preliminary vibration at high frequency.展开更多
It is customary to evaluate the sand reclamation efficiency by general standardmethod as sieve analysis etc.But the special method also can be used in the casewhere the weight of specimen sand is small and a more accu...It is customary to evaluate the sand reclamation efficiency by general standardmethod as sieve analysis etc.But the special method also can be used in the casewhere the weight of specimen sand is small and a more accurate result is expected.Inauthors’experiments,the grain-size analysis was carried out by an image analysingcomputer and the Na<sub>2</sub>O content analysis was done with a modified standard methodof acid consumption.From the results of analyses,it might be recognized that theCO<sub>2</sub>-sodium silicate bonded sand can be reclaimed by dry type vibration methodeffectively after pretreatment.The size and form of reclaimed sand grain are the sameas those of original new Sand and soda content in the remainder on the surface ofsand grain is about 0.I%.It is assumed that the sieve method may be replaced by theimage analysing computer in sand grain-size analysis in the future.It is also pro-posed that the titration method for measuring Na<sub>2</sub>O content may be necessary tobe studied further.展开更多
文摘Influences of frequency,amplitude,vibrating time,moisture in sand,thickness of sand layer and pretreatment of high frequency vibration and heating on sand reclamation were studied.Cured binder layers around sand grains are completely removed and original sand grains remain unbroken by vibration at a certain frequency and amplitude.Effectiveness of sand reclamation by the vibration method is correlated to the vibration force which depends on the combination of frequency and amplitude to a great extent.The optimum vibration condition is limited by the capacity of vibrator.Drying of used sand is required.The thickness of used sand is an important factor.Pretreatments of used sand are also required.Moreover,preheating in a certain temperature range is preferable to preliminary vibration at high frequency.
文摘It is customary to evaluate the sand reclamation efficiency by general standardmethod as sieve analysis etc.But the special method also can be used in the casewhere the weight of specimen sand is small and a more accurate result is expected.Inauthors’experiments,the grain-size analysis was carried out by an image analysingcomputer and the Na<sub>2</sub>O content analysis was done with a modified standard methodof acid consumption.From the results of analyses,it might be recognized that theCO<sub>2</sub>-sodium silicate bonded sand can be reclaimed by dry type vibration methodeffectively after pretreatment.The size and form of reclaimed sand grain are the sameas those of original new Sand and soda content in the remainder on the surface ofsand grain is about 0.I%.It is assumed that the sieve method may be replaced by theimage analysing computer in sand grain-size analysis in the future.It is also pro-posed that the titration method for measuring Na<sub>2</sub>O content may be necessary tobe studied further.
