The decision for a sawmill to spend big on new technology has rarely been more important or more difficult than it is now. Arguably the only time it was more critical was during the pits of the recent recession and it was precisely then that Westervelt’s Moundville sawmill in Alabama, US, was starting out on its due diligence process in preparation of a major upgrade from manual to automated grading.
The sawmill management team had been convinced for several years that an automated grading system would improve efficiencies and significantly increase trim values to make the Westervelt mill a far more profitable operation. Mill Manager Tommy Clemmons and his team were adamant that with markets being so poor that it was vital to invest in new technology immediately to remain competitive. The challenge would be to convince the parent company’s investment committee, which was understandably hesitant about making large capital expenditures at a time when cash flows were severely threatened.
“Like most industries, the forest product industry right now is in bad shape so Westervelt, like most companies, is watching its investments to make sure it only invests in really good projects,” Clemmons told International Forest Industries. “We went through a lot of data analysis to first of all convince ourselves that this would be a good project, and then we took it to our corporate investment committee and they thought it was too.”
“But we had to do a lot of homework – it wasn’t just a case of walking in and saying we want some money. It took several months to prepare that data through testing and analysis and then a couple of separate meetings of different sizes with committee members before the project was approved.” Approval came in January this year and the two-stage installation began in the northern summer.
Part of the testing process involved deciding on a supplier, which the Westervelt team quickly narrowed down to three. These candidates were then each given the chance to scan and grade a package of lumber that the mill had already thoroughly manually or hand-graded. This is a fairly common process and gives the mill an opportunity to compare the results from potential automated systems operating at industry speed against those returned from comprehensive internal grading of the same boards when stationary.
Oregon-based Lucidyne Technologies was the last company to receive the package and used its GradeScan® system to put the lumber through its paces. GradeScan delivered the best results and Lucidyne was subsequently awarded the contract.
“In our testing we felt that the GradeScan system did the best,” Clemmons said. “We’re a single-site mill so we rely completely on our quality to be able to always move our lumber, to get repeat business and maybe even get a little bit more money for our lumber based on that quality. We really didn’t want to mess with that so we got the system we thought could do the absolute best job possible in the grading.”
“We also felt very good about the information that comes out of the Lucidyne system. We really push our process improvement and the GradeScan system provides a whole lot of information that will help us to determine why some products are being downgraded so we can hopefully make improvements before the lumber gets to the finishing area.”
“With the GradeScan, we have an ability that we previously did not have to react quickly to our customers, which means we’re able to do more from a marketing standpoint in the future. In a sawmill, you can never just cut-to-order because you get a general quantity of roundwood at grades that always have some variation. But with a system like this, when we do get sales instructions from time-to-time we will have the flexibility to meet those instructions. It’s critical in the current environment to be flexible because you need to be able to move what you cut and if the sales team is asking for it then that means you can move it.”
“We felt that Lucidyne was the best fit for our needs and our feelings were confirmed by the reports we received from several other Lucidyne customers – there were nothing but rave reviews. When you keep hearing the same message out of everybody, you believe it.”
Westervelt will also eventually benefit from reduced labor but for the time being the manual graders have been redeployed elsewhere in the mill. Clemmons said natural attrition would gradually bring overall employee numbers down.
Lucidyne Marketing and Sales Director Bill Briskey said the company was pleased to have prevailed in the tender process and had wasted no time in implementing the GradeScan system into the Westervelt mill. The first step was visiting the mill to discuss the optimal system design. The flexibility of GradeScan meant that very few technical modifications were required at the mill but Westervelt has taken the opportunity to remodel its layout to maximize efficiencies.
“In most cases because of the flexibility of our system, it goes in fairly well without a lot of mechanical changes, however, Westervelt decided that, based on what it wanted to achieve and its commitment to automated grading, the layout of the grading line would be redesigned,” Briskey said.
“It’s running as a fully-automated mill so there’s no way of going back – these guys are very committed to making this work, which is sometimes what it takes for a mill to recognize its full operating potential. A lot of times people will leave a back-up system and that makes it too easy to go back to an out-dated system if there are any problems. In Westervelt’s case, the mill is committed, we’re committed, it has to work, so it’s going to get done.”
GradeScan is estimated to make about a $1 million difference to the Westervelt bottom line during its first full year of operation.
The technologies comprising the GradeScan® system have been in use since 1999 in secondary manufacturing applications but have only been integrated into a high-speed planer mill grading system for the last eight years. During that period, the system has constantly evolved with the aid of customer feedback and new technologies. Resolution and speed have increased to the point where it is currently operating successfully in one mill at a speed of 1,220 m/minute (4,000 feet/minute).
There are two parts to the GradeScan system, complementing the typical layout of a production line that includes both a lineal and a transverse section. The lineal portion is typically installed in line with the planer so lumber can leave the planer and head directly to the infeed of the GradeScan system. The system is designed to deal with the debris stream caused by the planing process, with manual cleaning on a two-hour cycle usually sufficient. The system can be lined up further downstream to minimise debris if desired.
Most of the scanning is done in the lineal section, which features color vision, geometric, density, tracheid, and other sensors. Sensors can be added to the system as need be and as technology allows. Other non-Lucidyne lineal external devices can be brought in, for example a moisture analyser that provides the moisture content along the full board length. Or an MSR machine to measure elasticity along the board and dictate a solution for preferential strength trimming, which is a departure from regular elasticity measuring systems that simply stipulate a strength value based on the weakest part of the board.
If possible, bow, crook, and twist are measured immediately after the boards leave the scanner and are still traveling on the planer outfeed conveyor. This allow the boards to be relaxed while being measured, and they show their true shap since they are not being mechanically restricted. Lucidyne's Warp Tunnel does this in a way that also removes some movement in case boards are bowed/twisted enough to oscillate while being scanned.
Following the lineal section, boards are separated on a lug chain in preparation for the transverse phase of the GradeScan system, which has three steps.
The first task is board identification, which recognizes boards that were previously scanned in the lineal section. Competitive systems must apply some sort of ink or paint marking during the lineal section and recognize the markings on the lug during the transverse section but the Lucidyne identification system has taken this concept to the next level.
“We take a picture of just a 30 inch section of the board on just one end in the transverse section and we compare that to what we saw going through the lineal section. True-Q identifies the boards by matching up the grain patterns – it’s like using the fingerprint of the board to identify it,” Briskey said. This avoids the mess and expense of spraying paint and ink in preference of a non-contact system, which can also recognize a board instantly from either surface rather than checking both sides for marking. “Since our lineal vision system is already looking at all four sides of the board, we only have to look at one face when the board gets to the lug chain.”
If it was not possible to measure warp on the planer outfeed belt, the next step is measuring the warp of the board – the bow, the twist and the crook (side-bend or spring). This ideally needs to be done with the board relaxed, which isn’t possible when it’s being held by rolls. This measurement is done using a Warp Bridge, which captures the board shape at every two feet along its length. This is done from the top only.
Finally, Lucidyne recommends that the mill incorporate a human check grader to monitor material handling and look for characteristics that the machine has not yet been trained to see. These can be indicated by limiting the grade or identifying a minimum trim using crayon marks, which are then picked up by the grade mark grader in the final part of the process. Or the check grader can simply apply manual grade and trim marks for the grade mark reader to see.
Other sensors that can be incorporated into the transverse section of the scanning process are acoustic and weight sensors –“pretty much anything you throw at us we can bring in because of the architecture of GradeScan ”, Briskey said.
He said the real standout features that differentiate GradeScan from other products on the market are its True-Q and sensor technologies. The True-Q system is a specialized technology for tracking the boards and keeping them “in queue”, hence the name; while Lucidyne’s engineers and scientists design most of GradeScan’s sensors and has patented inventions in multiple countries.
“The three things that are important to us in a sensor are the size, speed and resolution. The speed and the resolution are obvious – the more information you can get and the faster you can get it, the better job you can do. But the sensor package size is also critical . because, as the boards move about while being scanned, any separation between sensors introduces a potential for errors when trying to align the data, causing inconsistencies in the solutions you produce. Our implementation enables us to capture data from all our sensors at the same location along the board.”
GradeScan is predominantly supplied to the North American market but has begun to distribute into Australia and will soon be seen in parts of Southeast Asia as well. This part of the world is already familiar with Lucidyne as a company so is a logical place to begin international introduction of the GradeScan system.
Australia, however, does not know Lucidyne for its scanning technology but almost exclusively for its grade mark readers, of which there are several GMR installations. The company is currently trading off this recognition to expand its product base. Lucidyne has already successfully completed its first GradeScan installation in Australia. Commissioning of that project was achieved in one week.
Briskey said he has had enquiries from European mills about the technology but was yet to proactively consider taking GradeScan over the ditch and into Europe. He said setting up in Europe would take a significant increase in size and operational span, for which Lucidyne was not yet ready.
“We’re a fairly small company, which has its advantages and disadvantages. A move into Europe would take a definite increase in size and more aggressive approach that we’re not quite ready for yet,” he said. “I’d entertain a joint venture situation to see how the technology would go into a European mill but first I’d like to get over there and see the lay of the land.”
“A lot of companies will stub their toes because they try to branch out too quickly and spread themselves too thin. We’re open to an invitation to investigate opportunities but right now we have lots of opportunities in North America and Australasia as well as work to do to improve the technology so, for us, it’s really a case of one step at a time.”
Briskey believes the GradeScan system is appropriate for any mill that wants to improve its quality of scanning – even in Europe where the cut-to-length system has made mill-entry timber much more uniform. With that belief and the proven abilities of the GradeScan technology in diverse applications such as Westervelt, further installations of the system worldwide are a certainty in the future.
For another article on Westervelt featured in the magazine, Timber Processing, click here.