Venpap System for Paper Machine PRESS FELT CLEANING AND CONDITIONING Sunday, April 16, 2017 www.venpap.com
What is the Importance of Press NIPs? Mechanical Dewatering is 10 Times Cheaper than Thermal Drying Without a specific vacuum system designed to remove all of the shower water and appropriate felt conditioning, definite press inefficiencies can occur.
Sunday, April 16, 2017 www.venpap.com
The VenPap phenomenon is illustrated in this animation. A Venpap Blow Box blowing a mixture of hot air and steam is fixed above the vacuum box. Here, we subject felt to extreme conditioning along with its preheating. At the same time better permeability is accomplished and felt impurities are loosened. From there on, past the VenPap zone, a washed, dewatered and well prepared to absorb water felt runs to the press process. Vcuum Sunday, April 16, 2017 www.venpap.com
Animation beside illustrates a running Blow Box within the VenPap System. Air-steam mixture blown through the vacuum slot automatically penetrates the inside structure of felt. Blow Box preheats felt while thoroughly conditioning it. The diagram illustrates a typical steam box. A stream of pure steam flows through the slots that can be seen in the chart. The steam box operates just above the paper sheet and treats paper with hot steam in the widest possible range. The device’s main function is to pre-heat paper. A Steam box virtually does not impact the felt and does not affect its conditioning. www.venpap.com
VenPap Install VenPap Exemplary balance of steam: Use for VenPap System = - 500 lb /h ( one felt conditioning) Saving in the dryer = + 5500 lb/h Net Saving = +5000 lb/h Sunday, April 16, 2017 www.venpap.com
A major problem for contemporary, high-speed paper machines is the variable condition of the felt. After several days of work felts are characterized by varying permeability profile. Scanning felts in the cross direction to its movement shows in which sections the felts are inadequately prepared for the pressing process. The above diagram shows the control window for Venpap Blow Box operation. The PM’s operator sees the graph profile of water permeability of the felt. To regulate and improve the conditioning of weaker sections move Blow-Box sliders controllers under the graph. More at www.venpap.com/pilot.html Sunday, April 16, 2017 www.venpap.com
Change of the steam consumption for PM 220,000 t/year Sunday, April 16, 2017 www.venpap.com
Sunday, April 16, 2017 www.venpap.com
VenPap Procedures for Press Section STEP 1 – Check parameters of the felts: moisture, permeability, temperature STEP 2 - VenPap Project for a specific Press STEP 3 - Supply of equipment, running and adjustment STEP 4 – Measurements of the paper dryness, overview of results