The Moldrup process is carried out inside a pressure vessel using super-heated steam with a pressure between I and 12 bar (14.5-175psi). The steam pressure varies during the process according to a preprogrammed schedule and serves to ensure that the moisture content in the lumber never falls below 4%. This is an important advantage compared to the traditional systems for thermal modification, where the process is carried out using steam, oil or inert gasses at atmospheric pressure. At 180 – 200 degrees C (350-390F). the atmosphere is very dry when the pressure is around normal atmospheric pressure. The very dry conditions cause the moisture content to fall close to 0% and this results, very often, in many drying defects. By having pressurized steam in the chamber, it is possible to ensure that the moisture content does not fall below 4%. With the Moldrup system the number of drying defects is therefore significantly lower compared to the traditional systems.
The total process time is 6 – 8 hours compared to 1 – 2 days in the traditional systems.
Operating costs are significant lower compared to many of the traditional systems due to the shorter cycle time, reduction in drying defects and no use of chemicals or inert gas.
The system is very easy to operate and maintain
The Moldrup process has been used commercially in the flooring industry since 2001 The system is therefore well proven and large amount of experience nas been collected on the optimum schedules for the various timber species in the flooring industry. The long experience has also made it possrble to select the best possible materials and designs for making the equipment as durabe and long lasting as possible.
The high temperature used in thermo treatment of timber causes the timber to produce acetic acid. This creates a very corosive environment. To withstand the very corrosive environment and high temperatures, only top quality components such as stainless steel and temperature resistant valves, bearings etc are used in the construction of the plants Moldrup Systems offers a 5 years guarantee on the pressure vessel and 1 year guarantee on all other parts.