Polyester Glass Laminates

Polyester Glass Laminates 2017-07-09T21:24:25+00:00

Polyester Glass Laminates

This material is made up of fiberglass filaments impregnated with polyester resin, strengthened with heat and pressure to form solid and tough plates with high rigidity levels.

It is a thermosetting material and it is unsuitable for reforming or remolding.

It is better than phenolic products (finished with paper or cotton fabric support) as regards rigidity and arching resistance while slightly superior as regards heat resistance.

This type of insulating plate is suitable for use in the manufacture of collar plates, cotter pin slots for traction engines, collar plates for rotating field coils, panel spacers, busbars, connecting rods for various types of switches, boards for electric panels, as well as critical applications which require its superb resistance and dimensional stability.

Its good weather resistance makes it suitable for being used as insulating boards in rural transformers.

It satisfies ASTM D – 1532 standard in grades

– GPO – 1 General purpose
– GPO – 2 Flame resistant general purpose
– GPO – 3 Flame resistant and arching resistant

Chemical Resistance Chart

Composite % ºC
Transformer oil 100 110
Acetic acid 10 70
Acetic acid 50 50
Fatty acids 100 110
Citric acid 100 100
Nitric acid 5 50
Phosphoric acid 80 90
Sulfuric acid 25 90
Sulfuric acid 50 70
Tanic acid 100 90
Methanol 100 20
Ethanol 100 20
Aqua ammonia 5 60
Calcium hydroxide 525 40
Sodium hydroxide 10 80
Sodium hydroxide 25 50
Hydrogen peroxide 30 60
Sodium hypochlorite 15 70
Carbon monoxide 110
Sodium bicarbonate 100 100
Acetic acid* 100 100
Sodium cyanide 100 100
Sodium phosphate 100 100
Potassium nitrate 100 100
Potassium permanganate 100 100
Zinc chloride 100 100

Comparative Properties of Different Grades

Property Unit of measure Polyester glass cloth GP0 – 1 GP0 – 2 GP0 -3
Density G/cm3 1.78 1.70 1.75 1.75
Tensile strength Kg/cm2 1800 1200 1400 1500
Flexural strength Kg/cm2 2600 1400 1700 1700
Compression strength Kg/cm2 2600 1400 1800 1800
Impact strength Kg cm/cm 80 – 90 70 – 80 110 110
Module of elasticity Kg/cm2 x 103 210 190 190 200
Dielectric strength kv/mm 12 – 14 12 12 14
Power factor —- 0.020 – 0.040 0.02 0.02 0.03
Dielectric constant —- 4.5 4.0 4.2 4.6
Resistance to flame seg* 20 20 20
Arching resistance seg* 70 70 70 120
Humidity absorption % 0.3 0.4 0.4 0.4
Temperature range —- >B <F >B<F >B<F >B<F

Thickness and Tolerance Chart

Nominal Thickness (mm) Tolerance (mm) Nominal Thickness (mm) Tolerance (mm)
0.5 +- 0.03 7 +- 0.30
0.6 +- 0.03 7.5 +- 0.30
0.7 +- 0.05 8 +- 0.30
0.8 +- 0.05 9 +- 0.30
0.9 +- 0.07 10 +- 0.40
1.0 +- 0.10 11 +- 0.40
1.5 +- 0.10 12 +- 0.40
2.0 +- 0.12 13 +- 0.40
2.5 +- 0.12 14 +- 0.40
3.0 +- 0.15 15 +- 0.50
3.5 +- 0.15 16 +- 0.50
4.0 +- 0.15 17 +- 0.50
4.5 +- 0.15 18 +- 0.50
5.0 +- 0.20 19 +- 0.50
5.5 +- 0.20 20 +- 0.50
6.0 +- 0.20 21 +- 0.50
6.5 +- 0.20 22 +- 0.50

For thickness greater than the ones mentioned in the chart above, tolerance increases at 0.1 mm per 8 mm of increment of laminate thickness.

Maximum measurements: 1600 x 950mm