Scanning & Optimising
EXAMPLE OF AN ON-CARRIAGE SCANNING SETUP
An upgrade to an opening face scanning system is often a valuable solution for mills that have a manually tapered independent knee carriage working in combination with a slabber head (or chipper).
On a manually operated carriage, the operator aligns the log to the sawline often with the aid of a laser projected across the log. The taper of the log can be manually adjusted as the knees of the carriage are able to move independently of each other. Once aligned, an opening cut is selected for the slabber head, which will produce the desired opening face of the log and the first sized board to the saw.
While this process is adequate, it is heavily reliant on the judgment of the operator to ensure that the appropriate amount of the log is chipped away for the opening face. If too little is removed, the board may need to additional processing to recover the timber, which will be of a smaller dimension than that originally selected. If too much of the opening face is removed, valuable timber is chipped to waste and will never be recovered.
The addition of an opening face scanner to the existing system will aid in the calculation of this critical first cut, and reduce the heavy reliance on the operator’s judgement. By analysing the 3D profile of the face of the log that is presented to the slabber, the taper of the log and the positioning of the knees and slabber can be automated to get the best recovery from the log.
Such a scanning system effectively sits on top of the existing setworks and communicates the necessary positional information to the position controllers. This integration is usually possible with only minor modification to the existing control layout.
Jaymor has recently developed an on-carriage opening face scanner. Based on the JoeScan range of true-shape laser scanners (www.joescan.com), which have model options with laser lines down to 150mm spacings. Realistically, this 150mm spacing means that a detailed scan of the log (sufficient to make opening face calculations from) can be produced in as little as 75mm of carriage movement.
Download Jaymor Scanning & Optimising brochure (PDF, 1MB)
Jaymor is able to offer a true-shape edger optimiser to suit either lineal or transverse edger infeed systems. The optimisation computer provides value based optimisation, including options for wane allowance and skew-cutting if applicable.
The identification of the wane on the board is important as some cutting patterns can tolerate a set “wane allowance”, whereas others cannot accept any wane in resultant timber. While the best wane detection would be achieved with the laser scanners mounted in pairs at an angle above and either side of the board, it is possible to achieve sufficient resolution with only a single laser directly above the board. This arrangement does not detect steep wane edges very well, but can still distinguish between steep wane and a square edge due to the line of the board edge being straight if machine cut.
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To reduce the amount of travel required to scan the entire board, multiple scan zones are implemented. If the three of sets scan heads were mounted approximately 2m apart, it would be possible to achieve a full scan of a 6.2m board in a little over 2m of lineal travel. This provides time for the optimiser computer to decide on a solution and move the chipper heads and/or saws to the required position.
The Jaymor Edger Optimiser is based on the Joescan JS20 single line 3D true shape scanner (www.joescan.com). As the board is fed toward the saw station, the scanners would take multiple profiles of the board and produce a full representation of the board as illustrated in the diagram on the right:
Customised production reports are automatically generated by the hour, day or shift with configurable data to suit the needs of each individual mill. (See testimonial.)
Small log-line scanning
SCREENSHOT FROM A SIMPLE SCANNING SMALL LOG LINE SYSTEM
JOESCAN TRUE-SHAPE SCANNER SITTING TO ONE SIDE OF LOG INFEED CHAIN
It is often valuable to scan the logs entering the mill where the subsequent breakdown is achieved via a small log-line or multi-saw process. Unlike a carriage breakdown, where the operator will make several passes of the same log and as such is able to tailor the cut pattern to suit, small log-line systems usually require much fewer passes as such, much less operator input.
By analysing the profile of the log as it enters the mill, the scanner system is able to calculate the optimal cut pattern and issue the appropriate targets to the relevant machine centres. In doing so, it is possible to have several logs ‘queued’ in the system and being processed at once, with the optimising computer taking care of each individual log’s breakdown.
The scanning of the logs can either be achieved by a simple curtain scanner (producing either ‘X’ or ‘X+Y’ data), or with the use of a 3D true-shape scanner. The advantage of the true-shape scanner is that it give a much more accurate representation of the log’s profile and consequently, a more accurate solution is able to be calculated.
As all logs entering the mill are scanned, reports that outline each SED, LED, volume, sweep and length can be used to track not only the production of the mill, but also to audit the quality of the logs that are being received by the supplier. These reports can be customised to ensure the most valuable information for each individual mill is readily available.
Greenmill and drymill data collection
The ability to track the amount of timber processed through any mill can be a very valuable asset when analysing production, downtime or congestion areas in the mill. Jaymor has designed scanning systems and data collection software applications specifically to make this information easy to access and analyse.
The Jaymor Bean-counter is a system that has been designed to tally and store the dimensional information of timber produced from a greenmill. This is achieved by scanning the timber after it has been docked, and collating this information into customised reports. Such reports can be set up to run by hour, by shift or by day, with ample capacity for the data to be stored for several weeks.
The main features of the Bean-counter include:
- Monitoring of width, thickness and length with optional grade input.
- Intuitive touch-screen providing all user functionality and setup.
- Less than 300mm gap required for installation.
- Simple to install and calibrate (no need for expert technicians to come to site).
- Available in 500 x 250mm or 500 x 500mm versions.
- Optional encoder input for applications where timber speed is variable or stops.
- Data supplied in MS Excel format to ease further manipulation.
- Data logs transferred to a standard USB memory stick (other options available on request).
- Accurately scans boards to +/-1mm resolution.
- Large 2GB memory capacity for data storage.
In the Drymill it is often useful to scan and tally the timber as it exits a planer or moulding machine station. From here it is possible to automate the filling of packets to order or work list, and incorporate the inventory management system of the mill. This automation greatly reduces the amount of ‘double-entry’ required in manual tally systems and allows the mill to monitor their stock levels in “real-time”. See our grading and board sorting systems for more information.
DRYMILL BOARD SCANNER SYSTEM WITH
In-line moisture meters can be added onto the Drymill tally system to allow for sorting of timber that is “too wet” or “too dry”. This process allows kiln operators to tailor their charges to the average moisture content of the boards and achieve more consistent results. Moisture content information is also a valuable tool when examining the output from a kiln to confirm that the drying process is achieving the appropriate results.
See inline moisture meter solutions for more information.