摘要:
A lumber production machine and method for processing lumber uses a pressure vessel that can accommodate untreated lumber and an injection pipe disposed in the pressure vessel that is capable of injecting saturated steam into the pressure vessel. A pressure gauge is operatively coupled to pressure vessel to determine the pressure inside the pressure vessel. There is a mechanism for setting a minimum and maximum pressure inside the pressure vessel. Solenoid valves control injection of saturated steam from the injection pipe into the interior of the pressure vessel. A controller opens the solenoid valves when the minimum pressure is reached and closes the solenoid valve when the maximum pressure is reached. The method includes pressurizing and heating the lumber products with saturated steam by varying the pressure to achieve a uniform temperature inside the lumber. The pressurizing and heating step including providing saturated steam in the pressure-vessel type production machine; discharging the saturated steam of the production machine; introducing saturated steam back into the pressure-vessel type production machine for additional pressurization and heating. This introduction and discharging process can be repeated using varying pressures and the steam is provided providing in the machine in the range of 40 to 90 seconds.