first : the other supplier used same resin. RELPET from RELIANCE INDIA.
second : yes, we use the same machines and material lots.
I cannot imagine that the same material run on the same machine in a smaller would cause problems.
but, that`s what happened.
we made the preforms by 100% virgin, but it did not work, we still face the same problem.
today we tried TEXPET, another p.e.t resin supplier, nothing changed.
Mr.Len, and Mr.Louis,
thank you for the informations which will contribute of increasing our knowledge.
please be informed that even with the virgin mateial the problem still standing in the same case ( smell and bad taste ).
i could not imagine what makes the smaller preforms have this problem.
dryer dew piont = -40
melt termpreture = 285 each zone, except feeding zone 280.
mould tempreture = 270 - 280
charge pressure = 75, speed 70
shot cycle = 10sec
cooling time = 10sec ( the preform comes out warm )
waiting for your kind replies.