| 摘要 |
PURPOSE:To correct an expansion ratio to an optimum value immediately after pre-expanded particle is measured. CONSTITUTION:A steam pipe arrangement 11 is provided at a bottom of a pre-expanding machine body 2 for pre-expanding expanding resin pellets 1. A steam control valve device 12 for controlling quantity of steam to be supplied to the pre-expanding machine body 2 is provided in the steam pipe arrangement 11. A measuring device 5 for measuring pre-expanding particle supplied from the pre-expanding machine body 2 is provided adjacently to the pre-expanding machine body 2. A measuring signal from the measuring device 5 is compared with a set expansion ratio at a control device 6. When the measured value exceeds an allowable value of a set value, the quantity of steam of the pre- expanding machine body 2 is controlled by the steam control valve device 12 corresponding to a width dissociating from the allowable value. |
