Predryer Control System

Lignomat LMS-16PD

Instead of drying hardwood lumber from green to the desired final moisture content  in one kiln charge or exposing the lumber first to outside, uncontrollable weather conditions in an air drying Yard before going into the kiln, pre-drying lumber has been a valid and cost effective alternative.

Less degrade and lower cost in comparison to the previously mentioned  alternatives have made this approach very common in the US lumber industry.

The lumber is being stored in a large, warehouse type insulated building which allows to control a nice summer day climate of about 85°F and a relative humidity of about 60%. Fans circulate the air through the lumber either in a downdraft or cross flow arrangement. Under these ideal conditions lumber is being dried to approximately 30% moisture content (MC) and then finished in the conventional kilns to about 8% MC.

Due to the fact that usually a large amount of lumber is kept in the Predyer and that the lumber, being above fiber saturation, is at its most vulnerable stage during the drying process, great care has to be taken to control the climate conditions in the Predyer correctly.

Lignomat’s wireless technology used in the Predyer control system LMS-16PD  is perfectly up to the task. The use of freely movable Wireless Temperature and EMC Sensors allows to adopt to the ever changing loading patterns in a Predyer and the climate can be measured and controlled at locations where needed. Since no cables are required to connect sensors, the installation and use of the system is extremely easy.

The control system can be connected to an existing Lignomat Control system and can use the standard common features like remote access and collection of histories. All values for Temperature are displayed in one screen for easy balancing of the Predyer. All EMC values are displayed on a separate screen in the same fashion.

Priced competitively, this control system provides the ultimate tool to protect the lumber in the Predyer and assures drying of valuable lumber in an optimum drying time and with minimum degrade.