Pulper with extraction plate assembly having removable...

Metal treatment – Process of modifying or maintaining internal physical... – Producing or treating layered – bonded – welded – or...

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C148S528000, C029S447000

Reexamination Certificate

active

06623572

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to pulpers for a fiber suspension, and, more particularly, to pulpers having an extraction plate for separating good fibers from effluent.
2. Description of the Related Art
A pulper is used for making fibers which are used in a fiber suspension in a paper-making machine. The source of fiber may be, e.g., wood fiber in the form of virgin fiber or recycled fiber. The pulper grinds the source of fiber into individual fibers which are used in the fiber suspension in a paper-making machine.
It is known to use a pulper with a screen plate and a rotor which are disposed within a vessel. The rotor causes the source of fiber to rotate past the screen plate. Good fiber passes through a plurality of holes in the screen plate for further processing, while undesirable substances such as foreign matter, etc., do not pass through the holes in a screen plate and may be discarded.
It is also known to provide a screen plate with inserts which are respectively disposed within corresponding holes in a screen plate. The inserts are irremovably attached to the screen plate, such as by arc welding. The inserts may become worn over time. To replace the inserts, the screen plate must be removed from the pulper and the inserts are ground off flush with the screen plate. Additionally, it is often necessary to drill out. the inserts after the grinding operation since the penetration depth of the weld also extends into the screen plate. For these reasons, it is very difficult to replace the inserts in a conventional screen plate. In fact, it is often times less expensive to simply scrap and replace the screen plate.
What is needed in the art is a screen plate which may be easily repaired when the inserts become worn through use.
SUMMARY OF THE INVENTION
The present invention provides a pulper with an extraction plate assembly with a plurality of inserts which are removably attached to a wear plate.
The invention comprises, in one form thereof, a pulper for pulping a fiber suspension, including a vessel, an extraction plate assembly and a rotor. The extraction plate assembly is disposed within the vessel and includes a metal plate with a plurality of holes extending therethrough. A plurality of metal inserts are respectively disposed within the holes and project from the plate. Each insert is removably attached to the plate. A rotor is disposed within the vessel adjacent to the extraction plate assembly. The inserts are removably attached to the plate by brazing the inserts within the holes, or slightly shrinking the inserts using liquid nitrogen and placing the inserts in the holes.
An advantage of the present invention is that the inserts can be replaced without removing the extraction plate assembly and without disassembling the entire pulper.
Another advantage is that the inserts can be relatively easily changed from one shape to another, depending upon the specific application.


REFERENCES:
patent: 2527772 (1950-10-01), Stapley et al.
patent: 3713595 (1973-01-01), Craig et al.
patent: 3885745 (1975-05-01), Hankes et al.
patent: 4021274 (1977-05-01), Chadwick
patent: 4108692 (1978-08-01), Quinlan
patent: 4203782 (1980-05-01), Yamada et al.
patent: 4657636 (1987-04-01), Satomi
patent: 4708496 (1987-11-01), McPherson
patent: 4795560 (1989-01-01), Chupka et al.
patent: 4838961 (1989-06-01), Fukizawa et al.
patent: 4857119 (1989-08-01), Karst et al.
patent: 4880171 (1989-11-01), Garrett
patent: 5046246 (1991-09-01), Shepard et al.
patent: 5287613 (1994-02-01), Dahl
patent: 5435444 (1995-07-01), Satomi
patent: 5513691 (1996-05-01), Langner et al.
patent: 5614093 (1997-03-01), Mueggenburg et al.
patent: 5665207 (1997-09-01), Aikawa
patent: 5746845 (1998-05-01), Yoshida et al.
patent: 5798025 (1998-08-01), Iwashige
patent: 5858133 (1999-01-01), Keener
patent: 5966810 (1999-10-01), Chisnell et al.
patent: 6170576 (2001-01-01), Brunnert et al.
patent: 6254729 (2001-07-01), Doelle et al.
patent: 932670 (1973-08-01), None
patent: 1329333 (1994-05-01), None
patent: 1 180 617 (1964-10-01), None
patent: 25 32 375 (1977-02-01), None
patent: 197 02 044 (1998-04-01), None
patent: 0 275 967 (1988-07-01), None
patent: 1242086 (1971-08-01), None
patent: 0 562 930 (1993-03-01), None

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Pulper with extraction plate assembly having removable... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Pulper with extraction plate assembly having removable..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pulper with extraction plate assembly having removable... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3022304

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.