| 摘要 |
1,116,218. Casting processes. STEWARTS & LLOYDS Ltd. 22 June, 1965 [26 June, 1964], No. 26495/64. Heading B3F. A method of casting tubes comprises the steps of causing molten metal to rise, by gas pressure means, into a tubular die 4, holding the metal in the die, by the gas pressure, for a sufficient time for metal to freeze to a required thickness on to the wall of the die and thereafter removing the residual molten core of metal at a controlled rate of fall of at least 10 inches per second. Preferably the rate of fall is between 15 and 30 inches per second. The desired rate of fall may be obtained gravitationally or by applying gas pressure to the upper end of the die. The die 4 is supported in the cover member of a furnace body 1 which contains the molten metal 3. |
