| 摘要 |
An object of the present invention is to enable a wider range of control of physical properties of yarns. When relaxation heat treatment is performed, yarn feeding speeds of second godet rollers 22a, 22b, and 22c are controlled so that between every two second godet rollers which are adjacent to each other in a yarn running direction, the yarn feeding speed of the second godet roller located downstream in the yarn running direction is lower than the second godet roller located upstream in the yarn running direction, and temperatures of the second godet rollers 22a, 22b, and 22c are controlled so that the temperature of the heating roller 22c located most downstream in the yarn running direction is higher than or equal to the temperature of each of the remaining heating rollers 22a and 22b. When heat treatment under tension is performed, the yarn feeding speeds of the second godet rollers 22a, 22b, and 22c are controlled so that between every two second godet rollers which are adjacent to each other in the yarn running direction, the yarn feeding speed of the second godet roller located downstream in the yarn running direction is higher than the second godet roller located upstream in the yarn running direction, and the temperatures of the second godet rollers 22a, 22b, and 22c are controlled so that the temperature of the heating roller 22a located most upstream in the yarn running direction is higher than or equal to the temperature of each of the remaining heating rollers 22b and 22c. |
