| 摘要 |
1,157,105. Pitch bonded refractories. GENERAL REFRACTORIES CO. 17 Oct., 1966 [26 April, 1966], No. 46380/66. Heading C1J. 3 to 8% of pitch is hot mixed with a basic refractory 40-75% of which is coarse, 2¢ to 28 mesh; 5-30% is intermediate, 28 mesh to 325 mesh; and 10-40% is fine, at least 60% through 325 mesh, moulding at 150‹ F. and 7000 to 9000 p.s.i. and tempering at 400‹ to 600‹ F. for at least 5 hours. Specified refractories are magnesia (e.g. dead burned magnesite), calcined dolomite, calcined lime, forsteritic basic refractory or their mixtures. The term pitch includes tar and asphalt. |
