INDUSTRIES

Forest Product:

Panel Products:
Moisture control in the veneer, MDF, OSB and particle board industries is conducted more effectively using the Delta T moisture/dryer control system. The Delta T offers the following two major advantages that enable a minimum 30% reduction in product moisture content (MC) variation: (1) use of an “inside-the-dryer” moisture sensor; and (2) use of an automatic, continuous method that adjusts for water load changes entering with the feed. (more info)

Plywood:

The MC of thin-wood veneer used in plywood and manufactured lumber is controlled much more effectively using the Delta T moisture/dryer control system that is based on a model-based “inside-the-dryer” sensor, rather than an “after-the- fact” moisture sensors. The results of using this new control system are: less over and under-dried veneer produced, increased production of acceptable veneer, fewer blows, better gluing, and less breakage. (more info)

Block Conditioning:

Blocks used for veneer production are heated, either in steam chests or hot water vats, to soften for better processing at the lathe. Due to the wide variation in block diameters, and the fact that heat transfer varies inversely with block diameter, only about 60 – 65% of the core temperatures are within the acceptable range of 125 – 165 degrees F. The Delta T block conditioning control system increases that number to about 95% by directing the blocks to vats according to diameter, and pulling them according to core temperatures using heat transfer calculations. (more info)

Multi-Booth Lay up Line:

Multi-booth lay up lines are sometimes used for applying glue and laying up multiple layers of dried veneer prior to hot pressing into plywood. A line can have 4, 6 or 8 booths in series located above a conveyor. Glue is applied to the dried veneer as it travels through the booths and as additional sheets of veneer are added. Each booth has a spray nozzle that may be either manually or hydraulically height-adjusted to vary the amount of glue applied. Glue coverage measurement is periodically obtained by placing a pre-weighed two-inch wide x 4 ft long and 1/8” thick metal bar across the veneer prior to its entry into a booth. The glue-laden bar leaving the booth is removed and weighed and the coverage is calculated as lbs/Msq ft glue line. In contrast to the normal control method, the Delta T control uses spray nozzles mounted on hydraulic cylinders that are automatically adjusted to the correct height when the target coverage is entered into the computer. No costly flow meters are required, and the nozzles can be calibrated using only one stick measurement. Glue savings measured at one mill were measured at 5.2 Lbs/MSqFt glue line. (more info)

Lumber Kiln Moisture Control:

The Delta T multi-zone lumber kiln control system is the only “true” zone controlled lumber control system because of two important advantages: (1) it uses an error-free process variable for comparing zone drying as opposed to the commonly used TDAL, temperature drop across the Load, that does not accurately compare drying between zones/ and ; and (2) as soon as each zone’s lumber fiber saturation point (FSP) is reached, true zone control begins by comparing the drying rates in each zone and forcing all zones to converge toward a single mean moisture value for the entire kiln load. Since the Delta T control system is based on a mathematically derived model that relates temperature drop (delta t) to the moisture content, we know that individual zone TDALs are not comparable due to differences in the mass flow and temperature of air traveling through each zone. Consequently, the Delta T control system may be characterized as the only “true” zone-controlled system available. (more info)