Paper making and fiber liberation – Processes and products – With measuring – inspecting and/or testing
Patent
1997-04-07
1999-03-09
Silverman, Stanley S.
Paper making and fiber liberation
Processes and products
With measuring, inspecting and/or testing
162190, 162263, 162DIG7, 162364, 162262, D21F 148
Patent
active
058795138
DESCRIPTION:
BRIEF SUMMARY
This application is a 371 of PCT/F/95/00521 filed Sep. 22, 1995.
SPECIFICATION
The present invention relates to a procedure and to an apparatus for the drainage of the wire and/or press section of a paper machine.
BACKGROUND OF THE INVENTION
In the paper industry, drainage is implemented using suction pipes, suction boxes, suction rollers or equivalent provided with longitudinal gaps or holes against a wire screen, felt or equivalent which carries the wet web of paper. Each suction pipe is so placed that the wire, felt or equivalent passes over the gap or holes and drying is effected as the water is hurled by a centrifugal force into the roller trough. The water is gathered in the suction pipe and passed to a suitable collecting place. An apparatus of this type is presented in Finnish patent publication 77706 (Corres. to U.S. Pat. No. 4,329,201). In current systems, the vacuum is adjusted on the basis of pressure, by using various valve elements or by varying the rotational speed of a pump unit to maintain a desired pressure. Of the processes in a paper machine, the vacuum system is responsible for the highest power consumption. It also has an effect on the driving output and steam consumption of the press and wire section. In the solutions currently used, the adjustment of the vacuum capacity affects the negative pressure, but it has not been possible to reliably determine the effect of the adjustment on the drainage of the paper machine. An excessively high vacuum level is not beneficial to drainage. Instead, it increases the pumping costs and the costs resulting from the wear of fabrics and consumption of energy caused by increased friction.
The object of the present invention is to achieve a completely new solution that allows the drawbacks of known technology to be avoided.
SUMMARY OF THE INVENTION
The invention is based on an idea according to which the vacuum capacity is adjusted on the basis of water volume measurements with the aid of preprogrammed data.
The solution of the invention has numerous significant advantages. It makes it possible to control the drainage of a paper machine so that an optimal drainage situation is reached, with the result that the solids content e.g. after the press section is maximized. Therefore, maximal drainage for the wire and felt type in use is achieved. The runnability of the paper machine is improved. An adjustable vacuum system allows considerable savings to be made in energy consumption and has advantageous effects on paper quality.
BRIEF DESCRIPTION OF THE DRAWING
In the following, the invention is described by referring to the attached drawing FIG. 1, which is a diagrammatic representation of an apparatus as provided by the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The figure shows a simplified form of an apparatus for the drainage of the wire and/or press section of a paper machine. The apparatus comprises at least one suction pipe 1 having at least one gap or inlet 2 over which the felt, wire or equivalent web carrier 3 passes, vacuum elements 4, piping elements 5, 6 connecting the suction pipe 1 to the vacuum elements 4, drive elements 7, 8 for operating the vacuum devices 4 and creating a vacuum in the suction pipe, and elements 9, 10 for moving the felt, wire or equivalent over the suction pipe, thereby developing a vacuum for the drying of the felt, wire or equivalent. The apparatus is provided with regulating elements 11, 12 for the adjustment of the vacuum capacity and at least one element 13 located at least below the suction pipe for the measurement and/or adjustment of the amount of water drained, on the basis of which the vacuum capacity is adjusted by means of the regulating elements.
`Vacuum capacity` refers to a value which equals negative pressure (p) * pump yield value (Q).
The suction pipe 1 is placed in the apparatus in a manner known in itself and it has a gap or inlet 2 that opens towards the felt, wire or equivalent web carrier 3 passing over it. Connected to the suction pipe 1 is a pipe 5 whose one end communicat
REFERENCES:
patent: 1633189 (1927-06-01), Poirier
patent: 2877693 (1959-03-01), Poirier
patent: 3005490 (1961-10-01), Justus
patent: 3024839 (1962-03-01), Beachler
patent: 3066068 (1962-11-01), Calehuff et al.
patent: 3463700 (1969-08-01), Brewster et al.
patent: 4329201 (1982-05-01), Bolton
patent: 4891098 (1990-01-01), Renjilian et al.
patent: 5011577 (1991-04-01), Hansen et al.
patent: 5076890 (1991-12-01), Balembois
Ecopump OY
Fortuna Jos'e A.
Silverman Stanley S.
LandOfFree
Method and apparatus for the drainage of the wire and/or press s does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for the drainage of the wire and/or press s, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for the drainage of the wire and/or press s will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1316997