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September 2006 - The Logging and Sawmilling Journal

MANITOBA MILL UPGRADE

HITTING THE TARGETS

A new Valley Machine Works linear optimizing board edger is now in place at the Spruce Products sawmill and is hitting all the mill’s production and recovery targets.

By John Dietz

Western Canada has just become fertile new sales territory for Nackawic, New Brunswick, manufacturer Valley Machine Works Ltd. The company’s “flagship” product—its linear optimizing board edger—is now increasing efficiency and profit potential for a Swan River, Manitoba, lumber manufacturer, Spruce Products Limited (SPL).

Valley Machine Works, a familyowned company started by Joe Weirathmueller, builds equipment for small to medium-size sawmills.

“This is our first move west of Ontario. It’s a significant step for us,” says Hugh Hawley, Valley Machine general manager.

“The first 15 years of our existence, we sold almost exclusively into New England and the Maritimes. Over the last 10 years or so, we’ve expanded into the US South, into the Midwest, into Quebec and Ontario. Our first linear edger was built in 2001.”

Valley shipped its ninth unit of the computerized edger to Swan River in late 2005. Installed cost of the machine at Swan River was approximately $1.5 million.

“It’s been running since Christmas, and it’s meeting all the targets that were promised,” says Ward Perchuk, SPL president. “I would say it’s exceeded expectations. It had a fairly quick start-up curve. One comment I would make about Valley is that although there were the normal start-up issues, they stuck with us and resolved them.”

Spruce Products Limited figures it will receive a quick payback on the installation of a Valley Machine Works linear optimizing board edger at the company’s sawmill. The company calculates there will be an increase in “found” lumber in the range of 1.2 million board feet.

The Valley linear optimizing board edger is rated for a piece count of 25 to 40 per minute. Features include:

• one-inch side plates;

• six bottom feed rollers;

• four top rollers;

• arbor bearings at 3-7/16 inches;

• serpentine roller feed drive;

• air hold down for top rollers;

• single row ball bearings, for bottom feed rollers;

• single row ball bearings, for top rollers;

• top arbor configuration.

The unit at SPL has the optional three-saw board set-up, a hands-off infeed table, a centralized automatic lube system, three scanners and top chipping head.

In general, the Valley optimizer can be used for hardwood or softwood. Electricity, rather than hydraulics, powers the servo motor controls. It has fewer moving parts than other machines and is considered low maintenance. The installation requires minimal floor area. A unique skew-and-track sawbox eliminates the need for complex positioning on the infeed. It has feed speeds from 800 to 1,200 feet per minute.

The software, provided by USNR, can optimize for value or volume. The software is mostly self-regulating and requires minimal operator training.

Spruce Products last underwent a major mill upgrade in 1998. The company was processing about 35 million board feet per year, and had a recovery rate of approximately 245 board feet per cubic metre. Gradually, as the mill flow increased, the manually-operated edger became a bottleneck that restricted production. “The old one would get behind, and the recovery was no longer adequate,” Perchuk says.

Spruce Products considered several optimizing systems on the market for sawmills. “We found this machine to represent good value in the purchase price,” says Perchuk. “We looked at a number of Valley optimizers. We toured and saw them at work in New Brunswick and North Carolina, and were quite impressed with them.”

A recovery test earlier this year at Spruce Products showed the mill was capturing 266 board feet per cubic metres—representing a 2.1 per cent increase in “found” lumber.

In the investigation phase, Spruce Produces found the Valley optimizer would only require minor changes to the building. Essentially, it could “sit on the footprint” of the machine it would replace. It would also be easy to operate and to maintain. And it would repay the investment quickly. “We calculated that our increase of ‘found’ lumber would be in the range of 1.2 million board feet,” Perchuk says.

Spruce Products brought in a new mill manager, Rod Pidskalny, in October 2005. Pidskalny brought experience with similar processes and an optimizing edger from his previous work in Saskatchewan.“It’s been a very good year for me,” says Pidskalny. “In Saskatchewan, we had different equipment but essentially the same process.”

As of May 2006, the new edger was running at 800 feet a minute. “That’s the speed that meets our capacity right now. We’re averaging 19 or 20 boards a minute, but it has capacity for up to 25 boards a minute,” he says. “The piece count is a big jump for us. It allows the rest of the mill a lot more runtime because we’re not waiting while the edger is backed up.”

Previously, boards were fed manually into the edger. The operator set the saws, one board at a time, and would push each board into the saw. “Today, we did 6,500 boards. It was nowhere close to that before—probably 3,000 to 4,000,” Pidskalny says. In short, the computers scan, optimize and set the saws for each piece at a rate about twice the level that was achieved by a seasoned infeed operator.

Faster work at the edger put pressure on the trim line, he adds. The trim line had been running at about 75 lugs a minute; by May it was handling 82 lugs a minute. Sorting and stacking capacity also get more pressure, now that the edger is doubling its output. In time, they may need an upgrade there. Along with the higher production rate, recovery improved.

A recovery test in April showed the new mill was capturing 266 board feet per cubic metre of wood. That’s a 2.1 per cent increase in “found” lumber.

Installation of the edger was relatively easy, Pidskalny says. The first step was construction of a small control room, about six by 16 feet. The edger’s computers and electronic controls need to be kept in a dust-free, climate-controlled environment. Once that was set up, the rest was easy. “They just took out the old one, and installed the new. The mill kept running. We came up with a system to stockpile the wood that had to go to the edger outside, and re-entered it back into the process once the new board edger was up and running.”

The edger processes side slabs that come off SPL’s Sawquip canter line, as well as pieces coming off the trim line. It handles slabs up to 16 inches wide and 16 feet long.

As a slab comes through the edger, USNR 3-D TriCam sensor lasers measure it in three dimensions. The USNR software does a number of evaluations, according to priorities set by the mill operator, to achieve the optimum recovery. After making its selection, the software aligns three inline saws to make the appropriate cuts. It can also bring in a top chipping head, to produce a two-inch or one-inch board.

Parameters that guide the optimizing decisions can be set a few ways. “You custom design them for your mill,” Pidskalny says. “If you want to capture as much eight-inch or six-inch material as you can get, you can do that. Right now, it’s set up on strictly volume; we want to recover the most pieces available and minimize the waste.”

Valley Machine’s linear board optimizer has the ability to make a twoboard solution when it examines a slab. It can take a 12-inch slab and make it into two 2x6s or one 2x6 along with one 2x4 piece. It may “see” another solution. “It will optimize the two solutions,” Pidskalny says. “Suppose there’s a 2x4 in the front and a 2x6 in the back eight feet, but the piece is not perfectly straight inside. It kind of visualizes the slab.

It’ll go to the widest setting and send that through. It assumes the trim line will send back the remaining part of the slab to get that 4-inch piece.”

As a slab comes through the Valley Machine Works edger, lasers measure it in three dimensions. The software does a number of evaluations, according to priorities set by the mill operator, to achieve the optimum recovery.

Similarly, if a piece doesn’t meet specifications for two-inch material, the chipping head will re-man it to a one-inch piece.

Pidskalny likes this edger for a few reasons. “It has standardized processes, readily available components, standard parts and a simple, clean design. In terms of maintenance, it isn’t labour intensive; it doesn’t require hours and hours to do basic things.”

Valley Machine optimizers have several unique features, according to Hawley.

New to the Swan River installation is a set of “flitch tracker picker fingers.” The flitch tracker, he explains, separates finished product from edge material. “Before, we had picker fingers that were stationary. The ones at Spruce Products move according to the angle of the piece, and they stay hidden under the centre of the piece,” Hawley says. “It’s a little different methodology, and it’s providing significantly better separation of waste material.”

At the front of the lineal system, the operator is free to drop the piece onto the infeed belt without alignment. An apparatus at the front keeps it relatively centred on the belt. “It doesn’t, in any way, have to be perfect to the line you want to cut. That’s because, downstream, after the optimizer has made an image of the piece, it will tell the saw what angle to set the saw arbor to. Rather than trying to manipulate the piece, we manipulate the angle in the saw. There’s less opportunity for error in that situation,” he explains.

Several companies make machines for optimizing boards from slabs, but only two hold patented technology on a method for manipulating saws rather than material.

Valley moves the saws with its own unique system. “We use what I call a conventional shifting fork, essentially technology that’s been used in board edgers since Valley Machine started 23 years ago,” Hawley says. “Now, though, we’ve upgraded to a little better material. We use aircraft aluminum that wasn’t commonly used in the sawmill industry when we started. Our fork technology uses an aluminum collar and a phenolic fork to shift the saw.”

A final design element that sets the Valley optimizer apart, according to Hawley, is the use of all-electric servo positioners. “It’s a much cleaner system than hydraulic. It eliminates a lot of expensive valving and filtering, and a significant amount of heat.”

 


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