| 摘要 |
A film blowing production process comprises the following steps: (1) a bubble thickness measuring device continuously measures initial thicknesses of various points on a bubble along a circumferential direction; (2) various initial bump thickness control mechanisms start to perform a bubble thickness reducing operation; (3) select some from all normal point thickness control mechanisms for performing a bubble thickening operation; (4) calculate an absolute value d of the difference between c and b, i.e., d = |c - b|, wherein c is an average value of actual thicknesses of all the normal points of the bubble, including the thickened ones, after the thickening operation, and b is an average value of the adjusted initial bump thicknesses of the various initial bumps of the bubble after the thickness reducing operation; (5) compare d with e, wherein e is the maximum allowable difference between c and b, and proceed to step (6); and (6) a full-circumference thickness control mechanism reduces the full-circumference thickness of the bubble according to the measurement result of the bubble thickness measuring device, to reduce the average full-circumference thickness of the bubble to a, wherein a is a designed value for the thickness of the bubble. After the produced bubble is rolled, the accumulative error of thicknesses of various points is evenly distributed along an axial direction of the roll, thereby avoiding winder wrinkles, and a traditional mechanical rotational traction process and apparatus are also omitted. |
