Wipress

The Western India Plywood’s Ltd., an ISO 9001-2000 certified Company located in Kerala, South India is a large and reputed panel products manufacturer for over six decades. We produce different grades of Plywood, Fiberboard (hard board, insulation board etc.), Blackboards, Flush doors, Densified wood (Compreg) and components, mocked and knockdown Furniture, Pre-finished Fibre board, Engineered " Wood Floorings etc. Our motto is 'total utilization' as wood is a precious commodity and our integrated production facilities ensure complete utilization of wood and wood residues.

Precompressed Pressboard

WIPRESS, a hard and rigid board having high purity with excellent electrical and mechanical properties, is specifically produced for the high voltage and extra high voltage Transformer Industry. The product is made from imported virgin softwood sulphate pulp in our new production line using 'state of art technology'. Our experience over four decades in producing fibre boards and densified wood guarantees product compliance to lEC 60641 B.3.1 grade pressboard. Separate conditioning and testing facilities have been established for uninterrupted and speedy testing and evaluation of the raw materials and the product.

Pre compressed pressboards are cellulose based and are produced from kraft unbleached softwood pulp having high chemical purity and low conductivity. They are produced on intermittent board machine and compacted without added bonding agents in multi day-light press under heat and pressure to achieve required properties. The boards are characterized by high density, high purity, uniform thickness, dimensional stability, low compressibility, low shrinkage and high electrical strength

Pre compressed pressboards have high dielectric strength and find use as insulating material in different types of Power and Distribution Transformers, Capacitors, Switch Gears etc., in the form of winding cylinders, spacers, washers, keyway strips. etc.

Water : Quality Water is the most critical factor in the manufacture of Pressboard. Kerala, particularly Cannanore receiving more than 3000 mm of rainfall every year has an abundant resource of excellent quality water available throughout the year. This water is further treated by a most modern Water Treatment Plant.

Hydraulic Press : A most modern multiday-light Hydraulic Press of 1200 tonnes capacity of size 2.2 x 1.1 meters with Thermic Fluid Heating is used for the manufacture of Pre compressed Pressboards.

Reference Standard IEC 60641 – Part 3; Grade B.3.1


General

Appearance Hard rigid sheet light brown in colour with wire marks on both sides
Raw Material 100% Sulphate Pulp
Nominal Size 2.20 x 1.10 m
Thickness 0.5 to 6.0 mm
Thickness tolerance,%, max mm ≤ 1.6 ± 7.5 > 1.6 ± 5.0

Physical Properties

Density, g/cc, range mm ≤ 1.6 > 1.6 - 3.0 > 3.0 - 6.0 1.00 - 1.20 1.10 - 1.25 1.15 – 1.30
Moisture content, %, max 6
Ash content, %, max 1.10
Shrinkage, %, max MD CMD Thickness
  0.5 0.7 5.0
Oil absorption, %, min mm
≤ 1.6 11.0
> 1.6 - 3.0 9.0
> 3.0 – 6.0 7.0
Cohesion between plies Pass – split would show rupture of one or more plies and would have distinctly ragged appearance.
pH of aqueous extract, range 6.0 – 9.0

Mechanical

Tensile Strength, Mpa, min mm MD CMD
≤ 1.6 100 75
> 1.6 - 3.0 105 80
> 3.0 - 6.0 110 85
Elongation, %, min mm MD CMD
≤ 1.6 - 6.0 3.0 4.0
Compressibility C, %, max mm ≤ 1.6 10
> 1.6 - 3.0 7.5
> 3.0 - 6.0 5.0
Reversible part of Compressibility C rev, %, min mm ≤ 1.6 > 1.6 - 6.0 45 50

Electrical

Conductivity of aqueous extract, mS/m, max mm ≤ 1.6 5.0
> 1.6 - 3.0 6.0
> 3.0 - 6.0 8.0
Electric Strength kV/mm, min mm ≤ 1.6 In Air 12 In Oil 40
> 1.6 - 3.0 11 35
> 3.0 - 6.0 10 30