| 摘要 |
PURPOSE:To obtain extrusion molding method, which shows good extrusion performance even though no asbestos is added and in which the shape retention, resistance to frost damage and reduction of weight can be given to cement product. CONSTITUTION:Kneaded material prepared by adding 25-35 outer wt.% of water and 0.5-1.5 outer wt.% of extrusion assistant to 100wt.% of compounding material, which consists of 40-50wt.% of cement, 40-50wt.% of silica sand and 7-13wt.% of synthetic resin fiber fusible by the heat at autoclaving is added, is extruded on a pallet, which forms the rear of a formed article, so as to press and shape the formed article. Next and finally, the article is put into process to be cured and hardened at the temperature, which is higher than the melt temperature of the synthetic resin fiber so as to give the strength for the formed article and, at the same time, to get emptied of all the composition and reduce the weight of the article and to give the resistance to frost damage to the article. |
