Different Types of Industrial Timber – Uses and Properties
Sadanandam Anupoju
Reading time: 1 minute
What is Industrial Timber?
Industrial timber is nothing but timber product manufactured scientifically in factories. Because of its scientific nature, it is stronger and durable than ordinary timber materials. It also contains desired shape and size.
Different Types of Industrial Timber
Following are the different form of industrial timber:
Veneers
Plywood
Fiber boards
Impreg timbers
Compreg timbers
Hard boards
Glulam
Chip board
Block board
Flush door shutters
Veneers
Veneers are nothing but thin layers of wood which are obtained by cutting the wood with sharp knife in rotary cutter.
In rotary cutter, the wood log is rotated against the sharp knife or saw and cuts it into thin sheets. These thin sheets are dried in kilns and finally veneers are obtained.
Veneers are used to manufacture different wood products like plywood, block boards etc.
Plywood
Ply means thin. Plywood is a board obtained by adding thin layers of wood or veneers on one above each other. The joining of successive layers is done by suitable adhesives.
The layers are glued and pressed with some pressure either in hot or cold condition. In hot conditions 150 to 200oC temperature is marinated and hydraulic press is used to press the layers. In cold conditions, room temperature is maintained and 0.7 to 1.4 N/mm2 pressure is applied.
Plywood has so many uses. It is used for doors, partition walls, ceilings, paneling walls, formwork for concrete etc.
Due to its decorative appearance, it is used for buildings like theaters, auditoriums, temples, churches, restaurants etc. in architectural purpose.
Fiber Boards
Fiber boards are made of wood fibers, vegetable fibers etc. They are rigid boards and called as reconstructed wood.
The collected fibers are boiled in hot water and then transferred into closed vessel. Steam with low pressure is pumped into the vessel and pressure increased suddenly.
Due to sudden increment of pressure, the wood fibers explode and natural adhesive gets separated from the fibers. Then they are cleaned and spread on wire screen in the form of loose sheets. This matter is pressed in between steel plates and finally fiber boards are obtained.
Fiber boards are used for several purposes in construction industry such as for wall paneling, ceilings, partitions, flush doors, flooring material etc. They are also used as sound insulating material.
Impreg Timbers
Impreg timber is a timber covered fully or partly with resin. Thin layers of wood or veneers are taken and dipped in resin solution. Generally used resin is phenol formaldehyde.
The resin solution fills up the voids in the wood and consolidated mass occurs. Then it is heated at 150 to 160oC and finally impreg timber develops. This is available in market with different names such as sungloss, sunmica, Formica etc.
Impreg timber has good resistance against moisture, weathering, acids and electricity. It is strong, durable and provides beautiful appearance. It is used form making wood molds, furniture, decorative products etc.
Compreg Timbers
It is similar to impreg timber but in this case, the timber is cured under pressure conditions. So, it is more strengthened than impreg timber. Its specific gravity lies from 1.30 to 1.35.
Hard Boards
Hard board is usually 3 mm thick and made from wood pulp. Wood pulp is compressed with some pressure and made into solid boards. The top surface of board is smooth and hard while the bottom surface is rough. Hard boards are generally classified as three types as follows:
Types
Density (kg/m3)
Available thickness (mm)
Medium
480 – 800
6,8,10,12
Normal
800-1200
3.4.5.6.9.12
Tempered
>1200
3,4,5,6,9,12
Glulam
Glulam means glued and laminated wood. Solid wood veneers are glued to form sheets and then laminated with suitable resins.
This type of sheet is very much suitable in the construction of chemical factories, long span roofs in sports stadium, indoor swimming pools etc. Curved wood structures can also be constructed using glulam sheets.
Chip Board
Chip boards are another type of industrial timber which are made of wood particles or rice husk ash or bagasse. These are dissolved in resins for some time and heated. After then it is pressed with some pressure and boards are made. These are also called particle boards.
Block Board
Block board is a board containing core made of wood strips. The wood strips are generally obtained from the leftovers from solid timber conversion etc. These strips are glued and made into solid form.
Veneers are used as faces to cover this solid core. The width of core should not exceed 25mm. If the width of core is less than 7mm then it is called as lamin board.
Block boards are generally used for partitions, paneling, marine and river crafts, railway carriages etc.
