铸造中的联合工艺

采用水玻璃精铸生产销孔座系列产品遇到了烧砂问题(指在焙烧或浇注中模壳局部烧结并鼓胀导致铸件形成不规则的凹缺陷).由于水玻璃精铸中的涂料耐火度低,且涂料为层状、厚度大、易堆积而形成烧砂,但相同条件下水玻璃砂铸的铸件就不易出现烧砂.试验表明,在水玻璃精铸中局部采用水玻璃砂铸的联合工艺能十分有效地、经济地解决销孔座系列产品的烧砂问题.联合工艺经常是一种解决特殊铸件质量问题的有效方法.

Combined Process of Investment Casting and Sand Casting

The burn sand problem(Burn sand is a common defect in investment casting which means part of the shell mould gets sintered and deformed during the roasting or pouring)was found in investment casting of pinhole seat series products using sodium silicate sand.It is due to the low refractoriness and thick layer of the coating in the sodium silicate sand,which prones to accumulate,and then cause the burn sand easily.But under the same condition,burn sand does not occur in the sand casting process.The experiment...