LVL timber, also known as Laminated Veneer Lumber, is a versatile and popular choice of wood product used by many builders in the residential construction industry because of its extensive range of structural applications.
Wesbeam is Australia’s only manufacturer of LVL beams and LVL I-joistand produces a range of LVL products for the residential construction industry. This article summarises the manufacturing process of Wesbeam’s range of LVL products.
Sourcing the wood and the Log Yard:
Wesbeam sources the lumber used to engineer our LVL product from local and sustainably managed Western Australian forests located within a 450km radius of our Neerabup factory. Wesbeam uses three species of wood to make LVL. Two softwood species – Pinus pinaster and Pinus radiata and one hardwood specie – Eucalyptus diversicolor, also known as karri.
The log trucks are unloaded, and the logs are stored in defined locations, enabling individual deliveries to be tracked through the process. Logs pass through a scanner and are evaluated for defects, as all logs are required to meet specifications.
Logs are then stacked into bolt rows in preparation for presentation to the lathe.
All waste product is recovered for use. The bark is used for making mulch, the green and dry chip for particle board manufacture and the hardwood chip is either sold to the pulp and paper or biomass industries.
Debarking and the Lathe:
The secret of good LVL is a good veneer.
The logs enter the lathe, a computer calculates the largest recoverable volume from each log; and in seconds, the lathe peels perfect veneer sheets from each log. The veneer sheets are sorted and stored according to the amount of moisture they contain.
And then, sheet by sheet, they’re slowly dried until only around 6% of the moisture remains.
Drying and Cutting the Veneers:
Packs of similar moisture content are loaded into the dryer.
Hot air, generated by blowing air over natural gas heaters, is directed onto the sheets through a system of jet boxes.
Temperature and humidity control systems make continuous adjustments for optimal temperature and humidity while minimising veneer surface damage.
Prior to exiting the dryer, the sheets pass through a cooling section.
Ultrasonic sensors, a series of capacitive sensors, cameras and moisture brushes determine the strength, moisture content and physical properties of each veneer sheet.
Any sheets not making the grade are not wasted; the defective sections are removed and then the sheets are reassembled by a composer.
The dry veneer is then stacked into bins based on structural strength and moved to the dry veneer storage area.
The veneer is stored for a minimum of 18 hours prior to use on the press to ensure that any remaining moisture has equalised throughout the sheet.
At Wesbeam, we make many different kinds of LVL products; and each has its own recipe of veneer types and layup patterns.
The veneer recipe is generated by the line tech and the adhesive is determined as per the specifications that Wesbeam have developed specifically for each product.
The veneer sheets are then laid up end to end to form one continuous billet.
Veneer packs are loaded into the press line based on the structural recipe.
A saw trims each sheet to length and chamfers the edges.
The curtain coater delivers the exact quantity of glue to each sheet. The glue is mixed on site and is critical to the manufacturing process.
Natural defects in any given sheet are randomised and have minimal structural impact on the finished LVL.
At the completion of each layup sequence the pre-press opens, the billet is advanced, and the layup sequence recommences.
Hot pressing the LVL:
The billet then enters the hot press where heat and pressure form a continuous structural bond throughout the product.
Billets move to the hot press outfeed and are graded for visual defects. The billet is scanned to make sure it meets strict specifications.
Structural samples are cut and transferred to the laboratory for quality control testing.
Billets are stacked in the billet storage area for a minimum of 6 hours. Once quality control requirements are met, the billets are released to the Finishing Line.
The billet transporter presents billets to the finishing line crane.
Prior to ripping, the billet is printed with Australian Standard and Wesbeam product and manufacture details, providing a complete forest-to-dispatch audit trail for each piece of LVL.
The multi rip saw has two saw arbours. One that cuts from below the beam and one above.
The top arbour places a chamfer on the top edges of the beams. This saw floats on the top of the billet to ensure a uniform depth of chamfer.
The bottom arbour both cuts the billet to the required product width and chamfers the underside. The saw can be configured for multiple rip configurations.
Beams are separated on the grading deck and visually assessed prior to coating.
The spray booth applies purpose designed coatings for treatment identification, moisture resistance, and branding.
Beams are collated on the accumulation deck and stacked in layers to generate the required pack configurations.
Bearers are fed and strapped onto the packs with the automatic strapping machine.
Packs are cut to size using a band saw. Purpose designed blades cut the combination of softwood and hardwood veneers with minimal kerf wastage.
Packs are then wrapped and moved to despatch.
And that’s how Wesbeam manufactures more than 95,000 cubic metres of Australian manufactured LVL per year and builds better wood.
Wesbeam’s LVL products include e-beam and e-joist which are predominantly used for the construction of residential roof beams, wall frames and floor frames. This manufacturing process is what gives Wesbeam LVL its high strength and versatility.