Arrangement and Methods for Increasing Productivity of a Tissue Papermaking Machine or Minimizing its Dimensions

Abstract

A papermaking machine is provided for manufacturing a paper web, comprising a forming section having two clothings, a dewatering section comprising at least one paper manufacturing clothing, and a plurality of rotary rolls comprising guide rolls, each guide roll having two opposing flanges interconnected by a shell, each clothing running about some of the rotary rolls in a loop, wherein said papermaking machine is a tissue papermaking machine, at least one of the guide rolls is a lightweight guide roll supporting at least one of the clothings, and at least one of the shell and the flanges of said lightweight guide roll comprises a material with a density less than steel, wherein a weight of the lightweight guide roll is at least 10% less than a weight of a steel guide roll having the same dimensions and mechanical parameters. Associated devices and methods are also provided.

1 . A papermaking machine for manufacturing a paper web, the papermaking machine comprising at least a forming section having two clothings, a dewatering section comprising at least one paper web supporting clothing, and a plurality of rotary rolls, each of said rotary rolls having two opposing flanges and a shell interconnecting the flanges, the rotary rolls being configured to support the clothings, each clothing running about some of the rotary rolls in a loop, said rolls each having a diameter and being dimensioned for mechanical parameters including required calculated load, bending parameter and rotating speed, wherein said papermaking machine is a tissue papermaking machine,
 at least one of the rolls is a lightweight roll supporting at least one of the clothings of the tissue papermaking machine, and   at least one of the shell and the flanges of said lightweight roll comprising a material with a density less than steel, wherein a weight of the lightweight roll is at least 10% less than a weight of a similar roll comprised of steel and having the same dimensions and the same mechanical parameters.   
   
   
       2 . The tissue papermaking machine of  claim 1 , wherein the weight of the lightweight roll is reduced by at least between about 20% and about 30%, and most preferably by between about 60% and about 80%, as compared to the weight of the similar roll comprised of steel. 
   
   
       3 . The tissue papermaking machine of  claim 1 , wherein the lightweight roll has a diameter smaller than a diameter of the similar roll comprised of steel and having the same mechanical parameters. 
   
   
       4 . The tissue papermaking machine of  claim 1 , wherein the lightweight roll has a diameter larger than a diameter of the similar roll comprised of steel and having the same mechanical parameters. 
   
   
       5 . The tissue papermaking machine of  claim 1 , wherein the lightweight roll has a diameter equal to a diameter of the similar roll comprised of steel and is configured to rotate at a speed higher than a rotating speed of the similar roll comprised of steel. 
   
   
       6 . The tissue papermaking machine of  claim 1 , wherein the material of at least one of the shell and the flanges of at least one lightweight roll in at least one of the forming section and the dewatering section of the tissue machine has a density below about 7800 kg/m 3 , and preferably between about 500 kg/m 3  and about 2000 kg/m 3 . 
   
   
       7 . The tissue papermaking machine of  claim 1 , wherein at least one lightweight roll is at least partially comprised of the material having a density less than steel, and has the same mechanical parameters, with respect to required calculated load and bending parameter, as the similar roll comprised of steel. 
   
   
       8 . The tissue papermaking machine of  claim 1 , wherein the tissue papermaking machine further comprises a drying section having drying cylinders and a drying fabric forming a loop and running about the cylinders and at least one lightweight roll. 
   
   
       9 . The tissue papermaking machine of  claim 5 , wherein the tissue papermaking machine further comprises a winding section having a support clothing forming a loop and running about at least one lightweight roll. 
   
   
       10 . The tissue papermaking machine of  claim 1 , wherein said lightweight rolls comprise at least one of a lightweight alignment roll, a lightweight stretching roll, a lightweight forming roll, a lightweight tension roll and a lightweight spreader roll. 
   
   
       11 . The tissue papermaking machine of  claim 9 , wherein said lightweight rolls comprise at least 10% of all rolls in one of the forming and dewatering sections. 
   
   
       12 . The tissue papermaking machine of  claim 10 , wherein at least one lightweight roll is rotatingly driven by one of the paper web and one of the clothings. 
   
   
       13 . The tissue papermaking machine of  claim 1 , wherein the shell of the lightweight roll has a cover layer of another material. 
   
   
       14 . The tissue papermaking machine of  claim 1 , wherein at least one of the shell and the flanges of the lightweight roll is comprised of a composite material. 
   
   
       15 . The tissue papermaking machine of  claim 14 , wherein the composite material of the lightweight roll is one of a carbon fiber and a glass fiber material with resin matrix. 
   
   
       16 . The tissue papermaking machine of  claim 14 , wherein the composite material of the lightweight roll is a ceramic material. 
   
   
       17 . The tissue papermaking machine of  claim 1 , at least one of the shell and the flanges of the lightweight roll is comprised of a lightweight metal having a density less than steel, preferably a density of between about 2000 kg/m 3  and about 5000 kg/m 3 . 
   
   
       18 . The papermaking machine of  claim 1 , wherein the lightweight roll is a solid roll. 
   
   
       19 . A method of increasing an operation speed of a tissue papermaking machine, the tissue papermaking machine comprising at least a forming section having two clothings, a dewatering section comprising at least one paper web supporting clothing, and a plurality of rotary rolls, each of said rotary rolls having two opposing flanges, each with a mounting shaft, and a shell interconnecting the flanges, the rotary rolls being configured to support the clothings, each clothing running about some of the rotary rolls in a loop, said method comprising:
 substituting at least one of the shell and the flanges of a steel roll with a corresponding at least one of a shell and flanges comprised of a material having a lower density than steel and the same mechanical properties as steel.   
   
   
       20 . The method of  claim 19  further comprising:
 substituting at least 10% of the steel rolls in at least one section of the tissue papermaking machine with rolls at least partially comprised of the material having the lower density than steel and having a weight of between about 10% and about 90% of and the same mechanical parameters as the steel guide roll.   
   
   
       21 . A method of using a lightweight roll in a tissue papermaking machine, the lightweight roll comprising two opposing flanges and a shell interconnecting the flanges, wherein at least one of the shell and the flanges is comprised of a material with a density less than steel, wherein a weight of the lightweight roll is at least 10% less than a weight of a similar roll comprised of steel and having the same dimensions and the same mechanical parameters, each roll having a diameter and being dimensioned for mechanical parameters including calculated load, bending parameter and rotating speed, said method comprising:
 substituting at least one steel rotary roll with a lightweight roll having a weight of between about 10% and about 90% of and the same bending parameter as the steel rotary roll, each roll being configured for at least one of guiding and supporting at least one of a wire, a fabric, and a clothing in at least one of the sections of the tissue papermaking machine.   
   
   
       22 . A method of minimizing dimensions of a tissue papermaking machine having a given operation speed, comprising:
 substituting at least one steel rotary roll in at least one section of the tissue papermaking machine with a lightweight rotary roll having at least one of a shell and opposing flanges made comprised of a material having a lower density than steel and the same mechanical parameters as steel.   
   
   
       23 . The method of  claim 22  further comprising:
 at least one of guiding and supporting at least one of a wire, a fabric, and a clothing with the lightweight roll in at least one section of the tissue papermaking machine.   
   
   
       24 . A method of decreasing vibrations while increasing an operation speed of a tissue papermaking machine, the tissue papermaking machine comprising at least one of a forming section, a dewatering section, a drying section and a winding section, each section comprising at least one paper web supporting clothing and a plurality of rotary rolls, each of said rotary rolls having two opposing flanges and a shell interconnecting the flanges, the rotary rolls being configured to support the clothings, each clothing running about some of the rotary rolls in a loop, said method comprising:
 substituting at least one of the shell and the flanges of a steel rotary roll by the corresponding at least one of a shell and the flanges comprised of a material having a lower density than steel and the same mechanical properties as steel.   
   
   
       25 . A method of re-building a tissue papermaking machine with a given dimension and a required operation speed, the tissue papermaking machine comprising at least one of a forming section, a dewatering section, a drying section and a winding section, each section comprising at least one paper web supporting clothing and a plurality of rotary rolls, each of said rotary rolls having two flanges and a shell interconnecting the flanges, the rotary rolls being configured to support the clothings, each clothing running about the rotary rolls in a loop, said method comprising:
 substituting at least one of the shell and the flanges of a steel rotary roll with a corresponding at least one of a shell and flanges made of a material having a lower density than and the same mechanical properties as steel.