【正文】 Reduction of preform set T (max 3176。 C) Balancing the effect due to the different temperature of the air In continuous production the feedback should work around 4% TRAINING Optimization in continuous production 4 set Tair 空氣設定溫度 set Tpreform 瓶坯設定溫度 Tair 空氣實際溫度 Tpreform 瓶坯實際溫度 時間 溫度 之后 時間 溫度 以前 1st. 解決方法 Increase Tair set and ventilation 增加空氣設定溫度和排風 TRAINING Optimization in continuous production 4 Tair Tpreform set Tair set Tpreform time temperature After 2nd. 解決方法 Increasing lamp and ventilation power 增加燈管加熱功率和排風 time temperature Before TRAINING Optimization in continuous production 4 Tair Tpreform set Tair set Tpreform 3rd. SOLUTION Preform temperature set reduction 降低瓶坯設定溫度 time temperature Before time temperature After TRAINING Long period variations 5 What can change in the long period? 1. Environment temperature環(huán)境溫度 2. Temperature of preforms in stock瓶坯庫存溫度 What should I do? Optimize again the process: find the new set of the total power for the ovens, ventilation and modify the set temperature of air and preform. The ideal thermal profile doesn?t change! TRAINING Productivity change Which are the settings need to be changed in case of higher productivity? 1. Heatings: the preform temperature and the thermal profile need to remain the same 2. Thermal inversion: it is needed to guarantee the same difference of temperature between internal and external (the inversion must be increased) 3. Primary pressure: increasing the speed of the stretching rod, the primary air pressure must be increased (the bubble in primary has to remain the same) 4. Air inlet set: it could be necessary readjust the settings for primary and secondary air entry 5 TRAINING Productivity change: high productivity Which are the productivity limits ? 1. Ovens: To guarantee the sufficient heating power and a higher thermal inversion it should need increase the percentages of the lamps and increase the ventilation . Beyond a limit, the lamps will arrive to the saturation. For being able to heat ulteriorly the preform, the ventilation needs to be decreased. This will involve a minor thermal inversion and an overheating of the air of the oven (possible problem of overheating of the neck). 2. Air inlet: Higher is the speed of the stretching rods, greater must be the precision of the valves. pressure time: Decreasing the permanence time in cavity, the time available to cool the possible hot zone not stretched (bottle bottom) decreases. 5 TRAINING Productivity change: low productivity Which are the productivity limits ? : for too low speeds there could be a very high thermal inversion or even a thermal preform degradation. In order to decrease the inversion it is possible to switch off the first lamps or all the inlet side oven. No other particular problems need to be note, except to remember the PT100 . 2. Air inlet: lower is the stretching rod speed, lower must be the air pressure. It cannot be adjusted lower than bar and this can be a problem . 3. Stretching speed: decreasing the strecthing speed it can result a not good uniformity and obtain bottles with low mechanical proprties . Practically, decreasing the stretching speed it is equivalent to have low stretching ratio .