2-different types Seasoning of Timber| seasoning
Seasoning of Timber
This article is a process by which moisture content in a freshly cut the required tree is reduced to a suitable level. By doing this so the durability of timber is increased. The various methods of seasoning used may be classified into seasoning:
It may be air seasoning or water seasonings. Air seasonings are carried out in a shed with a platform. On about a 300-millimeter high platform timber balks are stacked. This Type of Care is taken to see that there is proper air circulation all around each timber balk timber. This time period, in a natural process moisture content, reduces. A well-seasoned timber contains only 15% moisture. This is slow but a good process of seasonings. Water seasonings are carried out on the banks of rivers. The thicker end of the timber is kept jointing upstream side. After a period of 2weeks – 4 weeks, these timbers are taken out. During this time period sap contained in the timbers are washed out to a great extent (Extention). After the timber is stalked in a shed with free air circulation (open space is very perfect).
In this type of method, timber is seasoned in a chamber (storage room) with regulated heat, controlled humidity, and proper air circulation, and this all monitoring. Seasonings can be completed in 4days to 5 days only. The different methods of seasonings are given below:
(seasoning)Boiling method: In this type of method, timber is immersed in natural water and then water is boiled for 3 hours to 4 hours. Then it’s dried slowly. It was Instead of boiling in this method, very hot water steam may be circulated on the timber. The process of seasonings is fast but very costly.
Kiln Seasoning: Kiln is an airtight chamber. Timber to be seasoned is placed inside it. Then fully saturated air with a temperature of 35°C to 38°C is forced into the kiln. The heat gradually reaches inside timber. Then this relative humidity is gradually reduced and the temperature is increased and maintained for the desired degree of moisture contents are achieved.
The kiln used may be stationary or progressive. In the progressive kiln the carriages carrying timber travel from one end of the kiln to another end gradually. This hot air is supplied from the discharging end so that temperature was increasing is gradual from charging end to discharging end ( this method is many processes are keeping). This method is used for seasonings on a larger scale.
Chemical Seasoning method: In this type of method, the timber is submerged in a solution of suitable salt. Then the timber is dried in a dry kiln. The preliminary treatment by chemical seasonings ensures uniform seasonings of outer and inner parts of timber.
Electrical Seasoning method: In this type of method, the high frequency alternate electric current is passed through the timber testing. Resistance to electric current is low (checking very carefully) when the moisture content in timber is high. As moisture content reduces the resistance reduces. The measure of resistance can be used to stop seasonings at an appropriate level.
However, it is a cost to the process. This technique has been tried in some plywood industries but not in the seasonings of timber on a mass scale.