The U.S. kiln-dries about 29 billion board feet of lumber annually. The product’s utility is wide ranging, from framing and finishing construction to furniture and other consumer goods. From forest to table, finished wood products can be found in nearly every home or business across the globe. But make no mistake, while wood is a commodity, getting it into a usable state is a meticulous and precise, multistep process.
The quality of the wood-drying process depends on three important factors: temperature, relative humidity and air circulation. Controlling all three factors helps a sawmill hit a moisture content target to produce the highest quality, most sought-after wood.
Measuring Temperature and Relative Humidity
For decades, measuring temperature and humidity required a wet bulb system. With this system, humidity is derived out of a complex calculation. Basically, two standard mercury thermometers are placed in the kiln—one covered with a wet cotton wick and the other mounted in the open air. Temperature differences between the two are used to calculate the relative humidity inside the kiln. From this calculation, the kiln’s operator will decide whether to adjust the temperature, open or close vents or change the fan circulation.
All these decisions have a direct and visible effect on the wood’s quality and aesthetic. Many times, these choices are complicated by their natural interdependence. It requires a highly skilled operator to unravel the puzzle of humidity extraction. Even then, there is much room for error, and not just in their strategy but also in the temperature measurement mechanism. Something as simple as not changing the water for the wick can cause faulty readings, putting the entire batch of wood in jeopardy.
Digital sensors reduce this error-prone process and provide more accurate readings, next-level automation and increased profits.
E+E Elektronik’s EE310 High-End Humidity and Temperature Sensor is designed specifically for industrial-grade applications like kiln drying. Our instruments boast durability and accurate readings. The sensor’s high-quality materials and engineering make it a state-of-the-art instrument. Designed for industrial use, the sensor probe is encased in stainless steel that is made to withstand high temperatures. Each sensor is protected from corrosion with our proprietary coating, ensuring it will survive for years.
Our sensors go beyond measurement and become a fundamental part of the process. With the ability to be linked to the kiln, the sensors can initiate a sequence of changes, like turning off the heater, opening vents or increasing fan speed, the same way an operator would. Simply put, these digital sensors take the place of a wet-bulb system, perform the calculations continuously and autonomously, and provide accurate and reliable results ensuring the highest quality product.
For more comprehensive insights, pair the EE310 humidity and temperature sensors with E+E Elektronik’s EE75 sensor, which measures air circulation. These digital sensors address all three principal factors for the most accurate wood drying, giving you the peace of mind that the readings will be reliable.
Why the Wet Bulb Method Is Going out of Style
The wet-bulb method for temperature and humidity readings may initially be the most cost-effective route for sawmills; however, the risk of a miscalculation and labour associated with maintaining it come with a hefty price tag. Collecting data via a wet bulb leaves a lot of room for error, as temperature readings are vulnerable to rusting probes, mechanical issues like the water freezing in the winter, over- or under-adjustments to other systems and more. With a lack of reliability at the beginning, there is little chance of a consistent process thereafter.
Alternatively, E+E Elektronik’s digital sensors pave the way for long-term profitability. They pay for themselves in less than a year, have been shown to last more than 15 years and significantly reduce manual operation costs. With these many benefits from automation, it’s hard to make the case for not going digital.
For more information about E+E Elektronik sensors and technology, check out our website at epluse.com
Matthew Nemeth is Managing Director in the U.S. for E + E Elektronik, an Austrian-based Internet-of-Things technology company that develops and manufactures sensors, transmitters, hand-helds and data loggers for air velocity, CO2, relative humidity, dew point, flow, moisture in oil, pressure and temperature. E+E operates a nationally accredited calibration lab and is appointed to maintain the National Standard for Humidity and Air Flow Speed in Austria.
Matthew can be reached at E + E
Elektronik USA 847-495-7744