Types of wood and disadvantages

Types of wood and disadvantages

1 - types of natural wood :

Timber is divided by a natural climatic zones to:

A - Woods soft dark color such as coniferous trees , including wood Sweden and grow in cold regions .

B - Woods medium hardness dark color , such as beech and oak wood and mahogany ... and grow in cold regions .

C - precious hardwoods such as oak and walnut , ebony and grow in the tropics . Prior to use, the use of any type of wood should be dried to reduce the percentage of water in it,

The types of drying :

1 - Altgfik steam and boiling water .

2 - drying ovens with natural air ducts .

3 - kiln drying with compressed air.

It consists of natural wood ( a section of the tree ) of the following :

Cortex , cambium , wood back, wood heart , the core , the annual rings , and the age of the tree is measured by the number of annual rings .

Defects timber :

Defects arise in the timber as a result of various factors, weather , and most important of these flaws :

1 - Contract: abound in softwood lumber such as wood white , and the node is a place contact the branch torso is notified that they may be separated during the work must therefore be removed machine that removed the contract, and they can be burned Beremus Incineration ( Babur ) .

2 - torsion : bends the branches as a result of the intensity of the movement of wind when the tree is small .

3 - rot : It is produced from the decomposition of materials Synovial in the tree.

4 - trauma : the faults appear in the cross section of the tree because of the drop at the cut trees and colliding heavily to the ground.

5 - aging : where it becomes the heart of the tree Ojoava and damage the wood part of the tree because of the delay in cutting the tree for a good time .

2 - Types of industrial timber :

A - sheets of plywood ( plywood ) : a layers the direction of the veins in the first layer perpendicular to the direction of the veins in the second layer , and plastered layers on top of each other with the pressure to ensure that no swollen when exposed to water , and not splitting panels when hammering nails in layers. And using a single number of layers least 3 layers , and each layer is called Ffinerh .

A picture of a wood and opposite note of its constituent layers

B - shingles latte :

Frequently used panels latte in the Household Furniture and Aalmketbi has many other uses .

The plates are divided into several types latte are:

1 - shingles latte in mass composed of strips of wood width not exceeding 25 mm and not less than 8 mm gathered and attached to a face -to-face and covered with sheets of double-sided natural wood .

2 - sheets of laminate latte : no more than a slide show for the 7 cm gathered and attached to a face -to-face to be a flat surface covered with sheets of double-sided natural wood .

3 - wood particleboard panels : in the form of sheets made ​​from a combination of grained wood adhesives with pressing and pressing .

4 - fibreboard : made ​​from a mixture of wood fibers and adhesives using heat and pressure .

5 - shingles plastics and melamine panels .