BIG ROLLS KEEP ON TURNING IN PAPER MILLS
The Granite Roll Radar Inspection (GRRI) method developed by Work Inc. improves the risk control of paper manufacturing machines:
- IN WORK SAFETY
- IN PRODUCTION OUTPUT
- IN PRODUCTION CERTAINTY
The condition of your stone roll can be checked by the GRRI method. The survey is guick and it does not damage the stone. An inspection of one roll at the factory lasts only 2-4 hours. If necessary, it is possible to inspect the roll even while the roll is in the machine during a stoppage. A preliminary description of your roll is provided immediately after the survey.
THE GRRI IS A PIONEER METHOD
Geo-Work has been performing radar surveys since 1987. During these years approximately 350 stone rolls have been inspected. Our GRRI method is already being used regularly at numerous paper mills around the world. This method was developed in cooperation with Technology Development Centre, insurance companies, Valmet Paper Machine Inc., and the major paper mills in Finland. Geo-Work Inc. is continually investing in the further development of this method.
GET A CLEAR PICTURE OF THE STONE ROLL’S INNER STRUCTURE
The Geo-Work GRRI method pinpoints targets not visible to the human eye, such as cracks or other factors affecting the safe use of the roll. The final report received by the client includes a comprehensive graphical computer printout which shows the condition of the stone roll, and the location and size of any cracks. Every stone roll is individual; the first survey maps the condition of the roll and the structure of the stone material. The necessity for a follow-up survey is determined in discussions with the client. The results of the first survey are compared with material produced in later surveys. If changes are observed in later surveys, there is reason to suspect that a crack in the stone roll has begun to enlarge, which may result in the shattering of the stone.
ROLL SECTION IMAGE EXAMPLES
A granite roll is measured at forty to fifty stations depending on the size of the roll. The following are some examples of typical images.
Cracks:
An internal crack generates a parabolic reflection on the radar profile. The suspected roll area is scanned at every two inches to measure the length and direction of the crack.
Structures:
Granite is not homogeneous. The radar measurements are used to lay out the structural direction of the granite which possibly indicates the weakest direction.
Mineral Enclaves:
The radar measurement detects large deviating targets in the shell, such as quartz, feldspar, and biotite enclaves (agglomerations). These reflections are different from those formed by cracks. The enclaves do not compromise safety, however, they may cause the roll surface to crumble locally affecting paper quality and roll life.
Rust:
Strong radar reflections caused by rust penetrations are often found between the end flange and the granite body. They are wide near the surface and weaken toward the roll center, contrary to the reflections by cracks.
Filling:
Variations in urethane or concrete filling in the center hole are detected by the radar. Dampers, centering supports, filler pipes may also be located.
Axial Scan:
There often is a step in the middle of the roll due to eccentric boring or sawing from each end. The shell thickness and variation in it are also measured.
GEO-WORK REFERENCE LIST OF GRANITE ROLL RADAR INSPECTIONS
Mills In Europe
SCA Laakirchen Ag.
A-4663 Laakirchen, Austria
Steyrermuhl Papier
Fabriks und Verlags Ag.
A- 4662 Steyrermuhl, Austria
KNP LEYKAM
B-3620 Lanaken, Belgium
Scapa-Kern Walzenservice Gmbh
A-4664 Laakirchen, Austria
Stora Garbonless Paper Gmbh
D-33691 Bielefelt, Germany
Parenco B.V.
NL-6870 Renkum, Netherlands
Soporcel Lavos
P-3080 Figueira Da Foz Codex,
Portugal
PAPEIS INAPA SA
P-2901 Setubal, Portugal
Stora Dalum A/S
DK-2550 Odense, Denmark
Stora Papyrus Grycksbo Ab
Grycksbo, Sweden
Enso Fine Papers Ltd.
Summa Paper Mill
FI-49420 Hamina, Finland
Enso Fine Papers Ltd.
Varkaus Paper Mill
FI-78201 Varkaus, Finland
Kaukas Oy
Voikkaa Paper Mill
FI-45910 Voikkaa, Finland
Metsä-Serla Oy
Kirkniemi Paper Mill
FI-08800 Kirkniemi, Finland
Veitsiluoto Oy
Kemi Paper Mill
FI-94830 Kemi, Finland
Yhtyneet Paperitehtaat Oy
Kaipola Paper Mill
FI-42220 Kaipola, Finland
Valmet Paper Machinery Inc.
FI-40101 Jyväskylä, Finland
Mills In Africa
Mondi-Paper
Merebank Mill
Durban, Reb.of South Africa
Sappi Kraft
Ngodwana Mill
Ngodwana 1209
Reb. of South Africa
Mills In Australia
Australian Paper
Maryvale Mill
Morwall, Victoria, Australia
Mills In New Zealand
Fletcher Challenge Paper
Tasman Mill
Kawerau, New Zealand
Mills In North America
Augusta Newsprint Co.
Augusta, Georgia, USA
Alabama River Newsprint Co.
Perdue Hill, Alabama, USA
Metso Paper
Columbus, Mississippi, USA
South East Paper Manufacturing Co.
Dublin, Georgia, USA
Georgia Pacific Co.
Ashdown Mill
Ashdown, Arkansas, USA
Domtar
Port Huron, Michigan, USA
Voith Paper
Appleton, USA
Mead Paper
Rumford Mill
Rumford, Maine, USA
Stora Enso
Duluth, Minnesota, USA
GNP
Millinocket, Maine, USA
Abitibi-Consolidated
Iroquois Falls Div.
Iroquois Falls, Ontario, Canada
Abitibi-Consolidated
Thunder Bay, Ontario, Canada
Donohue Inc.
Clermont, Quebec, Canada
Howe Sound Pulp and Paper Ltd.
Port Mellon, British Columbia
Canada
Abitibi-Consolidated Inc.
Grand Mere, Quebec, Canada
Weyerhaeuser Canada Ltd.
Prince Albert Pulp and Paper
Prince Albert, Saskatchewan,
Canada
Avenor Inc.
Gatineau, Quebec, Canada
Stora Enso
Port Hawkesbury
Nova Scotia, Canada
Eurocan
Kitimat, British Columbia, Canada
Bowater Thunder Bay
Thunder Bay, Ontario, Canada
Mills In South America
Ledesma S.A.A.I
Fa’brica De Papel
Jujuy, Argentina
Papelera Del Nevado
Toluca Mexico
Mills In Asia
Advance Agro Public Co.Ltd
Prachinburi, Thailand
