| abstract |
A method for providing pellets of extrusion compounded expandable polymeric compositions by (a) introducing a blowing agent and polymeric compound into an extruder, (b) extruding a composition containing the blowing agent and polymeric compound with discharge of the extrusion underwater through a pelleter at a temperature below blowing agent activation temperature, (c) supplying a stream of water across the die face of the pelleter at a predetermined first temperature sufficient to produce pellets, (d) supplying additional transport water downstream of the pelleter to further cool the pellets to a second predetermined temperature, and (e) separating the cooled pellets from the transport water. In an additional embodiment collecting the separated pellets, conditioning the transport water to the first predetermined temperature, and recycling the transport water to the die face. n In a process for extruding and transporting pellets in which an extruder discharges underwater through a pelleting device a method for controlling the temperature of the pellets in which transport water is supplied to the die plate of the pelleter at the first predetermined temperature sufficient to produce pellets and additional transport water supplied downstream of the pelleter further to cool the pellets to a predetermined second temperature. n In a method for transporting pelleted material a control system that comprises sensing and operating conditions, generating a signal according to the operating condition, and diverting flow of the pelleted material in response to that signal. |