Today’s ever-increasing market demands are rapidly forcing changes in the engineered wood and lumber industry as manufacturers attempt to remain economically competitive. Global competition is making these industries take a fresh look at ways to maximize productivity and reduce waste, wherever it exists in the production process.

One target area is the measurement errors from contact-type measurement methods, such as rotary encoders (also known as tachometers) and drive encoders. Engineered wood and lumber products have a common problem when it comes to in-process measurement: their surfaces are usually laden with debris, sometimes wet and slippery making it difficult for mechanical contact encoders to capture accurate length and speed readings. Increasing the contact pressure of the encoder wheel can scar or damage the product making it unusable for customer delivery. Sending the wrong length or speed signal via PLC can trigger an inaccurate cut. The undesirable result is costly: product scrap, maintenance downtime and lower product quality.

Manufacturers are looking to non-contact measurement techniques to accurately measure the length and speed of products in applications requiring the effective gauging of product length and control of speed, post-cut length and cutting operations, to name a few. Non-contact, laser-based measurement technology enables manufacturers to achieve the highest level of measurement accuracy in their production process while delivering valuable bottom-line results.

Non-contact, laser-based measurement has been applied to a wide variety of manufacturing processes. And NDC's LaserSpeed Pro non-contact measurement system has been paving the way. Here are two case studies that give you an inside look at this technology in action.

Cutting Control of Boards

Problem: A manufacturer of board products wanted to optimize product quality during its production process and was using mechanical wheel encoders at the production plant to measure the length and speed of product during cutting operations. However, the contact measurement method was inaccurate. The surfaces of the boards were not homogeneous and covered with dust and debris, causing the wheels of the mechanical encoder to slip. In order to minimize this slip, plant personnel would increase the contact pressure of the wheels. This approach damaged the surface of the boards and also quickly wore out the encoder wheels. Most important, the inaccurate length and speed information threw off the accuracy of the cutting and marking systems, causing synchronization issues between the fed boards and the transverse movement of the saw. The plant was experiencing length inaccuracies of up to 1%, which translated into significant material waste costs and product quality issues. The material loss amounted to hundreds of feet of scrap per production run, affecting the company’s profitability.

Solution: The manufacturer replaced its mechanical wheel encoders with a NDC's LaserSpeed Pro non-contact measurement system. Length and speed measurements were immediately and consistently accurate, unaffected by any mechanical issues. The laser system measures product speeds up to +/-26,000 ft/min (+/-8,000 m/min), and has a large measurement range to detect boards. The current length and speed measurements of the processed boards are updated at a rate of 1,000 times per second and are transferred at a frequency of up to 250 KHz to control the cutting system.

The manufacturer now has near 100% length control of its processed boards during cutting operations. The flexibility of the LaserSpeed Pro measurement system enabled it to be easily integrated with the processing line and with the cutting control system. This new system offers length and speed accuracy of better than +/-0.03% with +/-0.02% repeatability. This higher measurement accuracy also helps to ensure that the highest level of product quality is being achieved, which is expected by the manufacturer’s customers.

Post-Cut Length of Wall Panels

Problem: A wall panel company manufactures products in a variety of sizes for commercial and residential building applications. At one of its plants, the manufacturer needed a more accurate method of measuring the length of wall panels after they were cut. The production line used mechanical wheel encoders to perform the post-cut length measurements. However, the encoders presented numerous problems. Over time, they began to deliver inaccurate measurements due to dirt/debris build-up, resulting in calibration issues – as well as damaging the product. Length inaccuracies at the production line were as high as 2%. This equated to 20 feet per 1000 feet (6 m per 305 m) of product that had to be scrapped or reprocessed – a direct and unnecessary cost to the manufacturer. The short-term fix was to frequently shut down the line to clean-up, repair and re-calibrate the encoders, adding more cost due to downtime.

Solution: The wall panel manufacturer installed a LaserSpeed Pro measurement system after the cutting system to accurately measure the length of panels after they had been cut. This non-contact gauge delivered the following benefits to the manufacturer:

• Higher post-cut length accuracy and product quality
• Dramatic decrease in product scrap and material reprocessing translating into significant savings
• No damage to product
• Low cost of ownership due to reliable factory calibration and reduced maintenance

The Way Forward with Accurate, Non-Contact Measurement

Non-contact, laser length and speed measurement is steadily becoming the standard gauging technology for many engineered-wood products, solid wood other manufacturing applications, and is quickly replacing mechanical contact-type measurement techniques. The benefits of a non-contact measurement system like our LaserSpeed Pro gauge offers manufacturers a real competitive advantage. LaserSpeed Pro ensures no slippage or marking on all material types, shapes, colors and textures. It also has no moving parts to wear out and is permanently calibrated. This reduces the need to shut down your line for routine adjustments or maintenance so you maximize uptime. Companies that adopt this high-precision measurement technology quickly realize dividends in improved product quality and increased productivity with substantial cost savings.

To learn more about the LaserSpeed Pro measurement system.