| 摘要 |
The method involves taking up volume increase in mould resulting from ice formation using an extended plug extendably arranged in a hole at the top of the mould (2). The momentary ice formation in the mould is controlled by measuring the projecting length of the extended plug (6). The plug narrows in the direction towards th middle of the mould. The mould is emptied by removal of an extended plug (7) fitted at the bottom of the mould. The material used for the plugs is a polymer which obstructs the formation of ice. The lower plug is cylindrical with a longitudinal continuous thickness. The mould when filled with water (1) is exposed to a temperature below freezing point and ice is formed on its inside since the water nearest the mould walls is the first to be cooled. |
