Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
  • D21F3/00—Press section of machines for making continuous webs of paper
  • D21F3/02—Wet presses
  • D21F3/0209—Wet presses with extended press nip
  • D21F3/0218—Shoe presses

Definitions

• the present invention concerns a press arrangement for a moving web, comprising a cylindrical roll which forms a press zone with a glide belt supported by a shoe so formed that it brings the glide belt into press contact with a part of the roll circumference to form a nip and including lubricating means for obtaining a lubricating film between the belt and the shoe, and a counter roll located on the opposite side of the shoe from the press roll.
• One main purpose with the present invention is to achieve a press arrangement of the general type indicated in the introduction which makes it possible to adjust the position of the shoe around the center line of the press roll. Another purpose is to obtain a press arrangement which can be realized with regular and thus relatively inexpensive rolls.
• loading arrangements inside the shoe to deform it so as to compensate for roll deflection and achieve desired load distribution throughout the width of the pressure zones between the shoe and the rolls.
• the surface of the shoe in the area of the nip is in continuous contact with the belt via a lubricating film, from the entrance of the nip and the lubricating means including openings for introducing the lubricant under pressure in the load zones and canals for pressure equalization and removal of lubricant.
• the shoe is adjustable within limits around the center line of the press roll. This allows adjustment to a desired pressure profile in the direction of motion in the nip.
• fig. 1 is an endview of the embodiment of the invention as a partial crossection
• fig. 2 is a sideview of the mechanism in accordance with fig. 1 as a partial transverse vertical section
• fig. 3 is a transverse vertical section of shoe in accordance with the invention, to illustrate the flow of lubricant
• fig. 4 is a partial endview of the embodiment, where the crossectionof the upper part of the shoe is shown to illustrate the introduction of lubricant to the nip area between the press roll and the shoe, and
• fig. 5 shows an endview of an embodiment of the mechanism according to the invention to illustrate the adjustability of the shoe around the centerline of the press roll. Description of preferred embodiments
• Pigs. 1 and 2 show a press arrangement for a moving web 2.
• the arrangement includes a pressnip for receiving the moving web, formed between a cylindrical press roll 4 and a glide belt 6.
• the glide belt is slidingly supported on and wraps a shoe 8 with such a form that it makes the glide belt follow a part of the circumference of roll 4 to form the nip.
• Supply mechanisms 10 are provided to supply lubricant for a lubricating film via canals 12 between the glide belt 6 and shoe 8.
• the shoe 8 is supported by counter roll T4 which is situated on the opposite side of the shoe relative to the press roll 4, whereby the side of the shoe 8 facing the counter roll 14 is non-concave.
• loading mechanisms 16 may be e.g. pressure cylinders or bellows.
• a number of bellows 18 along the width of the shoe 8 are shown in fig. 2.
• Arrows 20 indicate the external loads on the roll journals' 22, which cause said rolls to deflect in operation.
• nip area As well as lubricant supply to the arrangement according to the invention shall now be described in more detail with reference to figs. 3 and 4.
• a supply duct 30 for lubricant is connected with nozzles 32 for the supply of lubricant under pressure between the shoe 8 and glide belt 6 in the nip area.
• a further supply duct 34 with nozzles 36, as well as equallizing canals 38 are also shown.
• the duct 30 is connected to a lubricant supply pipe 40, whereby the corresponding return pipe is shown at 42.
• a lubricant supply pipe 40 With 44 is indicated an endring which rotates with the glide belt.
• the endring 44 is fixedwith a connection including a st ⁇ pring 46 and a boIt 48serewed into the flange 50 on the shoe 8..
• the shoe 8 is further adjustable within limits around the centerline 51 of the press roll 4 which is schematically illustrated in fig. 5 with arrow 52. This adjustment of the shoe 8 can be realized in a manner not shown here by introducing forces on the endflanges 50.
• the adjustability of the shoe 8 makes it possible to optimize web geometry before and after the nip, as well as to influence the pressure profile in the nip. The latter is demonstrated by a pressure diagram 54 drawn onto the figure.
• the invention can be applied e. g. to remove water from a moving web in a papermachine, whereby the web is fed into the nip in a conventional manner together with one or two felts which receive the water. Another area of use is surface finishing of the web further on in the process.

Landscapes

• Paper (AREA)
• Press Drives And Press Lines (AREA)

Priority Applications (2)

Applications Claiming Priority (4)

Publications (1)

Family

ID=26660974

Family Applications (1)

Country Status (4)

Cited By (7)

Families Citing this family (2)

Citations (3)

• 1992
  • 1992-01-24 AT AT92904341T patent/ATE125893T1/de active
  • 1992-01-24 WO PCT/SE1992/000041 patent/WO1992013134A1/en not_active Ceased
  • 1992-01-24 EP EP92904341A patent/EP0575353B1/de not_active Expired - Lifetime
  • 1992-01-24 DE DE69203860T patent/DE69203860T2/de not_active Expired - Fee Related

Patent Citations (3)

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