近年来,我厂用水玻璃砂型生产碳钢铸件时常出现一种特殊的气孔,它不同于一般所见的皮下气孔和侵入性气孔。严重时约占总气孔废品率的30％左右,我们称它为“表皮气孔”。它多产生在排气不畅的暗冒口铸型或暗冒口比明冒口多的铸型里,它的外貌特征是:气孔区域 In recent years, I plant sodium silicate sand production of carbon steel castings often appear a special type of pores, it is different from the general view of the subcutaneous and invasive stomatal pores. Seriously account for about 30% of the total stomata rejection rate, we call it “epidermal stomatal.” It is often produced in the poor exhaust of the dark riser mold or dark riser than the riser in the mold, its appearance is characterized by: stomatal area