PVC-U molding profile extruder control system based on lonworks
By studying the dual-screw profile extruder used in PVC-U molding processing, presents a temperature computer control system in which a combined-control strategy of on-off control, fuzzy-control and integral-control were adaptive elected. The control system used Lonworks constructing a net to regulate the extruder's sub-areas temperature in line. App effect shows that the temperature control precision and the method of multi-subarea control in line with Lonworks filedbus has better effect than those sub-areas self-governed control, and can prevent PVC-U decompounding in the processing effectively, so the character of PVC-U manufacture could be improved.
A Fuzzy-PID Control System of PTFE Sintering Furnace Based on Lonworks
This note introduces an industrial control system which adopts fuzzy-PID and Lonworks. According to the character of a class of time-delay and great inertia first-order system, we chose a combined-control strategy that On-off control or Fuzzy-control or PID control strategy were selected automatically, so accurate control to the four PTFE (Polytetrafluoro-ethylene) molding furnace sintering process such as sintering temperature, sintering time, cooling speed etc were achieved. App effect shows, temperature control precision is 0.5%, initial tracking error, maximum exceed error and final error are 2.5, 2.0 and 2.0 Celsius respectively. It proves that the combined-control system is better than the singularity structural such as PID or Fuzzy in fleetness and robustness and steady-state precision.
The effect of heat press on the structure and properties of PTFE-based composites.
PTFE-based composite dielectrics whit high strength and low loss are acquired by heat press. The influence of the parameters on the dielectric's microstructure, electric property and mechanical property is investigated. The microstructure is observed by means of SEM and phase composition analyzed by XRD. On the basis of the investigation, an optimum heat press system is established.