Fabric and use of the fabric in a tissue machine

Patent metadata

Field	Value
Publication number	US-2022228317-A1
Application number	US-202017608607-A
Country	US
Kind code	A1
Filing date	Mar 12, 2020
Priority date	May 3, 2019
Publication date	Jul 21, 2022
Grant date	—

Abstract

A fabric, in particular a felt, for use in a machine for producing a tissue web, has a base structure, which has a textile structure with MD threads, and at least one layer of nonwoven fibers. The MD threads predominantly or as a whole have a diameter ranging between 0.25 mm and 0.45 mm, in particular between 0.3 mm and 0.35 mm, and the thread density of the MD threads is more than 37%, in particular between 37% and 45%. There is also described a machine and a method for producing a tissue web using such a fabric.

First claim

1 - 13 . (canceled)

14 . A fabric for use in a machine for producing a tissue web, the fabric comprising:
a base structure being a woven textile structure with machine direction (MD) threads and cross-machine direction (CD) threads; said MD threads wholly or predominantly having a diameter of between 0.25 mm and 0.45 mm and said MD threads having a thread density of more than 37%; and at least one layer of nonwoven fibers.

15 . The fabric according to claim 14 , wherein at least one of the following is true:
said MD threads have a diameter of between 0.3 mm and 0.35 mm; or said MD threads have a thread density of between 37% and 45%.

16 . The fabric according to claim 14 , wherein:
said base structure is composed of two endless woven layers or of two woven layers that have been made endless; each of said two woven layers has said MD threads which, wholly or predominantly, have a diameter of between 0.25 mm and 0.45 mm; and each of said two woven layers has said MD threads with a thread density of more than 37%.

17 . The fabric according to claim 14 , wherein said textile structure is a flatweave, wherein warp threads of a loom provide said MD threads of the fabric and said flatweave is made endless by connecting front ends thereof.

18 . The fabric according to claim 17 , wherein the front ends are welded to form a welded connection.

19 . The fabric according to claim 14 , wherein at least some of said CD threads are twisted threads.

20 . The fabric according to claim 19 , wherein 50% or more of said CD threads are twisted threads.

21 . The fabric according to claim 14 , wherein the fabric has a thickness of 3.5 mm or less.

22 . The fabric according to claim 21 , wherein the fabric has a thickness of between 2.5 mm and 3 mm.

23 . The fabric according to claim 14 , wherein a weight of the fabric lies between 750 g/m 2 and 1250 g/m 2 .

24 . The fabric according to claim 23 , wherein the weight of the fabric lies between 900 g/m 2 and 1100 g/m 2 .

25 . The fabric according to claim 14 , wherein a proportion by weight of said nonwoven layers corresponds at most to a proportion by weight of said base structure.

26 . The fabric according to claim 25 , wherein the proportion by weight of said nonwoven layers is at most ⅔ of the proportion by weight of said base structure.

27 . A machine for producing a tissue web, comprising;
a press device with at least one press nip; and at least one fabric according to claim 14 disposed to run through said at least one press nip during an operation of said press device.

28 . The machine according to claim 27 , wherein said at least one press nip is an extended nip.

29 . The machine according to claim 27 , wherein said press device has a wastewater trap configured to collect water which has been removed from the tissue web in said at least one press nip.

30 . A method for producing a tissue web, the method comprising: providing a machine according to claim 22 and producing the tissue web in said machine.

31 . The method according to claim 30 , which comprises dewatering the tissue web in the press device by nip dewatering, and wholly or partly collecting water thus removed by a wastewater trap.

32 . The method according to claim 31 , wherein the nip dewatering makes up more than 10% of a total dewatering quantity of the press device.

33 . The method according to claim 32 , which comprises dewatering the tissue web in the at least one nip by between 20% and 50%.

Assignees

• Voith Patent Gmbh

Inventors

• Klaschka Susanne
• Eberhardt Robert
• Walkenhaus Hubert

Classifications

• D21F3/045

  including at least one extended press nip · CPC title

• D21F11/14

  Making cellulose wadding, filter or blotting paper · CPC title

• D21F3/0281

  in combination with a dryer roll · CPC title

• D21F7/083 Primary

  Multi-layer felts · CPC title

• D21F7/10

  Seams thereof · CPC title