White board paper machine
When the papermaking machine has a certain width of papermaking, a certain speed, and a certain amount of papermaking, the size of the opening of the quantitative valve on the outlet pipe of the sizing pump is adjusted and controlled, and the adjustment and control of the sizing pump in the pulping pool is performed. The purpose of the pulp pump inlet slurry flow.
In the condition of stable slurry concentration, adjusting and controlling the flow rate means adjusting and controlling the amount of absolute dry pulp fed into the feed pump unit per unit time. The papermaking machine must have a certain copy width, a constant speed, and a certain amount of papermaking. Under the circumstances, it is equivalent to controlling the quantification of paper machine products.
The concentration regulator is generally installed on the outlet pipe of the slurry pump sizing pump. The concentration sensor is arranged on the outlet pipe of the sizing pump, the electric/pneumatic slurry dilution water regulating valve is arranged on the inlet pipeline of the sizing pump, and another concentration control cabinet (box) ) Connected with the above two facilities to form an electrical control unit. This system is called slurry concentration control system.
In order to automatically adjust the ration of paper products controlled by the paper machine, an electromagnetic flow meter, an electric/pneumatic quantitative control valve, and the above electrical control unit are also arranged on the discharge line of the slurry pool. This system is called slurry volume adjustment control system.
The principle of concentration adjustment and control is achieved by adding dilution water at the inlet of the slurry pump, measuring the concentration at the outlet of the slurry pump, and reducing the slurry concentration as a means to complete the concentration adjustment control.
A set of pre-flow transmission system with a set of slurry volume adjustment control system; with good conditions, a slurry concentration adjustment control system is also provided on the inlet and outlet pipelines of the slurry distribution pump. The purpose of doing so is that through two adjustments and controls, the slurry concentration from the pulp sizing pump to the slush pump inlet is more stable. Because the amount of one-time adjustment and control concentration is limited, the slurry concentration fluctuates greatly and easily exceeds the adjustment and control range. At this time, secondary adjustment and control are required.