我厂熔铜坩埚原来用本地出产的白石罐代替,用自然通风;发现的缺点有:(1)熔化速度慢——因每次烤罐约须3小时,所以每天8小时就能化两罐;(2)熔化量小——每罐仅能熔化60公斤左右; The original melting pot of crucible in our factory was replaced by locally produced Shiraishi can with natural ventilation. The disadvantages are as follows: (1) The melting speed is slow - it takes about 3 hours for each baking, so two cans ; (2) a small amount of melting - each tank can only melt about 60 kg;