Brief Review and Mathematical Modelling of Air Cushioned Pressurized Paper Machine Headbox

Today, the requirement of high grade papers is increasing day by day. To cater the need of high quality papers, new high-speed paper machines are being developed constantly. The whole economy of a pulp and paper industry depends on the quality of paper produced, quality of paper depends on the efficient operation of the major part of paper industry – paper machine. Paper machine is the heart of paper industry and has many subsystems. One of the important subsystem of paper machine is Headbox. To have the desired quality papers, efficient working of headbox is highly required. To have desired operation from headbox, its precise control is necessary. The precise modelling of headbox, leads to design of efficient controllers for its proper control to get the desired response. This paper presents the mathematical modelling of headbox along with a brief review of various research performed on headbox.

Stability analysis of paper machine headbox using a new PI(D) tuning technique

Paper, today, has made an important place in human’s life. Being an important commodity, paper has different qualities throughout the globe. As the technology is advancing, paper is being used for numerous applications and need of good quality paper is increasing daily. To have papers of desirable quality, paper machines with latest technology are developed. However, the quality of paper principally depends on the prime element of paper machine i.e. Headbox. Headbox is a highly non-linear Multi-input Multi-output (MIMO) component of paper machine and requires a precise control of its major parameters to get good quality papers which eventually responsible for sustained economy of pulp and paper industry. In past few decades, headbox has been a key element for research. Researchers have developed different control algorithms for headbox. This paper presents stability analysis of paper machine headbox using a new technique of Proportional – Integral – Derivative (PID) controller design namely Extended Forced Oscillation method (EFO). Also, the paper presents a comparative analysis of EFO method of PID tuning with the conventional Ziegler - Nichols(ZN) tuning technique based on transient characteristics and performance indices of headbox.