core making
5.A new core-making process of resin sand cured by acetal of gas-process is introduced in this uaper.
7.By applying ihe potential method to the hardening process of water glass CO_2 sand,the time of blowing CO_2 can be determined accurately,the productivity of molding and core- making can be increased,CO_2 can be saved and cast quality can be improved.
8.The Present situation of energy utilizing in foundry industry was analyzed, the main effective energy saving techniques and their application was described in aspects of melting and heating systems, moulding and core-making processes and equipments, low-stress cast irons, as-cast nodular irons, feeder-less method of nodular reclaiming of cupola gas, and so on.
9.The quality of furan sand castings is usually better than clay sand castings, however, some defects are also very easy take place with furan sand castings such as blow hole, metal penetration, veining, cracking, slag inclusion, hardness too low, surface recarburation, surface sulphuration, nodularity degeneration etc, which were usually caused by improper raw materials selection, improper method design, incorrect moulding or/and core-making.
