Maintaining fabric performance is essential in order to achieve targets of productivity, paper quality, cost and safety on the paper machine. However, fabrics in the forming, press, dryer and after coater sections behave like filters to trap and hold contamination. Traditional methods of cleaning fabrics often cause negative side effects such as having to use corrosive and hazardous chemicals, barrier coatings attaching to fabrics and sheet property variations caused by high pressure showers. Also, today's furnish introduces increasing amounts of contaminants while outdated efforts to clean fabrics simply shift the contamination to the next sections, affecting the runnability of the paper machine. New traversing cleaning systems have been developed in cooperation between paper mills, fabric designers and high pressure water technologists. These solutions are now running successfully on some of the most demanding applications. In forming, the concentration of water jets can greatly reduce the number of wet end breaks, reduce waves in the sheet and minimize spray and mist. Improved cleaning systems for press fabrics can reduce moisture variation and lower the amount and frequency of the use of cleaning chemicals while improving machine runnability. A unique cleaning head can be matched to the surface and structure of dryer fabrics to remove more contamination. In the after coater sections a combined cleaning and drying system allows continuous on-line cleaning of the fabric to ensure high quality for coated papers. These developments in cleaning technology, using a complete concept throughout the paper machine, bring benefits in servicing, availability of the equipment and the performance of paper machine fabrics.
展开▼
