PU abin nadi rufe Roll kafa inji, mai kyau forming da allura sakamako. Kuma muna ba da injin gudu biyu, 15m/min da 30m/min a matsayin zaɓi.
Don wannan injin kofa na abin nadi na PU, muna ba da gudu biyu azaman zaɓi:
1.15m/min, ginshiƙi na mashin ɗin zai fara bugawa kafin yanke.
Kuma ga injin 30m/min, yana yankewa sannan ana buga naushi.