April 2000 - Logging and Sawmilling Journal

When you first come around the bend of the Miramichi River, the sprawling oriented strand board plant looks just as it always did-then you notice that the sign that used to say "Eagle Forest Products" has been changed to read "Weyerhaeuser Miramichi". But that's only one of the changes taking place at this Highend OSB operation in New Brunswick. The mill was first established in 1996 when OSB entrepreneur John E Godfrey took a written off old particleboard plant and reinvented it as a modern, state of the art OSB operation. Product requirements and environmental standards have changed since then, however, and there have been major investments in both of these areas.

Along with technical changes came changes in ownership, starting in January 1999, when MacMillan Bloedel-an original partner with Godfrey's Chatham Forest Products, Temple Inland Forest Products, Stone and Webster Construction and Eagle Trust, a native funding group-bought out the entire group and became sole owner. Later that year, Weyerhaeuser, the world's largest producer of softwood lumber and market pulp and the second largest producer of OSB, acquired MacMillan Bloedel, and the Weyerhaeuser sign went up in New Brunswick.

The major effect of the move is that what started out as a "standalone" mill in a brutally competitive commodity market now has the stability, financial backing and market expertise of one of the world's forestry giants. While only time will tell where the mill will fit into Weyerhaeuser's overall plan, it seems to work neatly into the new owner's requirements for top quality product, high production and good relations both internally and externally.

Certainly the market demand for OSB has been growing steadily, partly because of its lower cost compared to plywood-the only comparable product-and because the product has been tailored carefully to meet the requirements of both the traditional construction industry and a wide variety of specialized applications.

Plant upgrades have responded to production and environmental demands, but there also appears to be a low key but determined plan to maintain the 24-hour/seven day a week schedule, no matter what emergencies arise. A $9 million improvement to the wood room includes a third flaker, a unique method for bypassing the debarkers and a three to four day storage area for white wood.

In the event of unanticipated maintenance or other problems, two flakers can supply full demand, stored white wood can replace flaker output for a short time and debarked wood or cores from a nearby veneer plant can come in directly through a wall opening - even if the wood room is down. The main process itself is unchanged: logs move from hot ponds to self cleaning tanks and are raised to debarkers, with control over the wood mix of the moment.

Material is then moved to the CAE disk flakers, with hog fuel diverted to a GGS thermal system which supplies heat for the plant, press and hot ponds. Three MEC Dryers control moisture levels and McConnell wood burners utilize the fines. Flakes move on to be coated in the COIL resin blenders and are fed to the eight foot Schenck forming lines where they are separated into two surface and two core levels, which are brought together to form an eight foot wide, endless "sandwich". This is cut into 24foot lengths and fed into the huge 8' x 24', twelve opening Pathex Press, which heats and compresses the resin and wax coated strands into rigid sheets.

A move into producing OSB for use in OSB/wood I beams saw Weyerhaeuser Miramichi working directly with a major I beam manufacturer to ensure the OSB being manufactured at the mill met customer requirements. This meant increased resin, increased density and a special OSB thickness just for this one company.

As the sheets come out of the press, they are cut and trimmed to a precise 4' x 8' by a Globe Machinery trim saw system and sander, which has been upgraded with an inline tongue and groove machine producing 19/32" and 23/32" panels. At this point everything is piled, spray painted on the edges, packaged and taken to the loading docks. The mill's specialized approach is well illustrated by its move into production of top of the line OSB used for the web in the OSB/wood I beams that are increasingly replacing solid wood and metal supporting beams.

Getting into this market was complicated by the lack of standards- manufacturers of these beams developed individual standards by testing the available high quality OSB and determining what was needed for their particular product. "We worked with a major I beam manufacturer in New Brunswick, who takes the largest part of our web quality output, to meet their requirements," says Chris Grotterod, transportation and marketing manager for Weyerhaeuser Miramichi.

"That meant increased resin, increased density and special tolerances-we make a special thickness for them. One day's run for us provides approximately a month's supply for them." Maintaining the carefully developed standards requires extensive testing on every millrun of the product. The mill does in-house tests on panels from each production run: for internal bonding, modules of elasticity, modules of rupture and wet and dry "imitation of nature" cycles. In addition, the web material is subjected to bend testing and samples are sent to the University of New Brunswick in Fredericton for large scale "rail shear" testing on that institution's larger test equipment.

Each batch is held at the mill until all tests are in, and only then is product shipped to the customer. In the early Eagle Forest days, the strands-slices cut from hardwoods by special flaking equipment -were approximately 3 3/4" long. Now, to increase strength, decrease fines and maximize utilization of raw material, Weyerhaeuser has gone to 4 1/2" strands, the maximum its equipment can produce. A mix of 60 per cent aspen and 40 per cent red maple, white and yellow birch is used.

On the environmental side, two years ago the mill installed a wet ESP (wet electrostatic precipitator), which has reduced the output of its particulate substantially. In fact, Grotterod points out "our emissions are now almost entirely water vapour and are far below our allowable limits." One of the challenges faced by all OSB producers is moisture control, for two quite different reasons.

If the wood, wax and resin mix contains excess moisture when it is put in the press, gas in the form of water vapour is produced which-when the press is opened-can actually make the panels explode. To avoid this possibility, moisture is reduced to about six per cent of what is present in the flaked strands and, when the panels leave the press, they have only about 1 1/2 to two per cent total moisture.

An ongoing problem with all materials made of wood is swelling when exposed to moisture, especially if it is very dry. Weyerhaeuser Miramichi operators have found six per cent to be the ideal "equilibrium" level and steps are taken to return the panels to this level. That approach to achieving an optimum moisture level, along with larger strands, improved resins and minor changes in the process, have resulted in a third generation OSB which has minimized the problem.

The workforce at the mill is made up of 145 employees, including part time and casual, largely recruited locally and trained in house. They produce 418,000 cubic metres of OSB a year, requiring 600,000 cubic metres of wood. About 60 per cent of this wood comes from a Crown land lease, with the balance coming from woodlot owners and small contractors. This translates into some 300 to 400 additional workers to harvest and haul, putting a total of $24 million in wood payments and $8 million in salaries and benefits into the regional economy-and, in the end, supplying demanding customers with the high end OSB they need.

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The former Eagle Forest Products OSB mill, now part of Weyerhaeuser, has been successful at ramping up to produce high quality OSB.

By Harold Hatheway