This invention discloses an automated control method and
system for the production of spandex
spinning oil. The method uses a DCS (
Distributed Control System) to detect and self-check the tank level, utilities, and pump / valve status. Upon successful self-check, production access is unlocked; otherwise, it is locked and an alarm is triggered. After unlocking, process parameters from the formula
library are retrieved. Material is weighed via a variable frequency pump
PID controller linked to a weighing sensor, and the feed flow rate is controlled by
fuzzy PID, following the feeding sequence and
timer intervals. The DCS issues a
grinding command, collecting particle size data in real time; if the particle size does not meet the standard, the
grinding time is extended until it does. Heating and stirring are initiated based on the
mixing tank level
signal, with timed temperature increases to the set value and then maintained. After the two processes are completed, the ground material is fed into the
mixing tank for secondary stirring. Successful sampling triggers filling, with
fuzzy PID controlling the filling flow rate. Once the liquid level is reached, the valve is closed, and a delayed cleaning process is initiated. After filling is complete, the entire line is
shut down. This invention solves the problems of fixed PID
control parameters and insufficient
interlocking of all processes in traditional PID control methods.