Increasing machine speeds, challenging press technologies, new pulp types and new chemistries all increase the demand on press felts. Optimum felt and press section runnability depends on maintaining “like-new” felt characteristics for a longer period of time. This can only be accomplished with an effective conditioning program.

The type and use of a felt conditioning system has a profound effect on the runnability of the felt and the press section of the paper machine. The first step in an effective felt conditioning program is an in-depth analysis of the felt contaminants present. Based upon this analysis, an optimum felt conditioning program involving both a mechanical and a chemical approach can be developed. Mechanical conditioning includes the use of various showers and vacuum boxes.
Chemical conditioning utilizes the components of the mechanical conditioning system to apply chemicals to the felt for contaminant removal.

During pressing, water that contains solids, fines, and other contaminants is removed from the sheet and transferred to the felt. The types of components found in the analyses of wet felts depend upon the wet end chemistry and final sheet characteristics of a system. Solids that are not removed and accumulate in the felt are called fill-up. Over 10% fill-up is considered a heavily filled condition.

An optimum felt conditioning system utilizes both mechanical and chemical means to keep felts open and all felts should be conditioned from start-up throughout life. There are a great range of mechanical and chemical methods available for cleaning a felt. It is possible and advisable to tailor the methods used to the type of felt contaminants, machine geometry and operating conditions that exist in an individual press section. Selection and application of the proper method will pay important dividends in reduced clothing costs, higher quality production and overall higher operating efficiencies.

An effective felt conditioning system accomplishes the following:
1. Detaches foreign objects imbedded in the felt either chemically or mechanically.
2. Dilutes or suspends solids through the application of sufficient water.
3. Removes solids and water through a suction system.

Anna 
Sales manger 
Hebei Defeng Polyester Fiber Co.,Ltd 
Add: Wugong town west, Raoyang county, Hengshui, Hebei, China 
Tel: 86-311-67699480 
Fax: 86-311-67699480 
Mail: bella@china-polyestermesh.com 
Website: www.china-polyestermesh.com 

Tag: felt, press felt