3248 High Strength Epoxy Resin Glass
3248 High Strength Epoxy Resin Glass
Rigid Laminated Sheet (G11)
Standard No.:Q/DSJ-180-2000
3248 high strength epoxy resin class rigid laminated sheet is made from alkali-free glass fabric treated with KH560 and impregnated with epoxy resin. It is made at high temperature and high pressure.
3248 has high heat resistance and excellent mechanical property. It is suitable for making insulating structural parts and components in F-class electric motor and electric apparatus which have high requirements under the condition of thermal state. It also can be used in the condition of moisture and in the transformer oil.
1 Technical requirements
1.1 Appearance
Its surface should be flat and smooth, free of bubbles, wrinkles and crackles and other defects such as scuffing, dent and uneven colors, slight scuffing and stain are allowed. Edges should show net cuts and be free from delamination and crackles.
1.2 Dimensions and tolerance
1.2.1 The length and width are as shown in Form 1
Form 1 mm
|
Width and length |
Tolerance |
|
450～980 |
±15 |
|
＞990～1980 |
±25 |
1.2.2 Nominal thickness and tolerance are as shown in Form 2
Form 2 mm
|
Nominal thickness |
Tolerance |
Nominal thickness |
Tolerance |
|
0.5 0.6 0.8 1.0 1.2 1.6 2.0 2.5 3.0 4.0 5.0 6.0 8.0 |
±0.12 ±0.13 ±0.16 ±0.18 ±0.21 ±0.24 ±0.28 ±0.33 ±0.37 ±0.45 ±0.52 ±0.60 ±0.72 |
10 12 14 16 20 25 30 35 40 45 50 60 80 |
±0.82 ±0.94 ±1.02 ±1.12 ±1.30 ±1.50 ±1.70 ±1.95 ±2.10 ±2.30 ±2.45 ±2.50 ±2.80 |
|
Note: The product of non-nominal thickness is settled upon negotiation between sellers and buyers, its deviation adopts the value of the next bigger nominal thickness. |
|||
1.3 Bending deflection
As shown in Form 3
Form 3 mm
|
Thickness |
Bending deflection |
|
|
1000 Ruler length |
500 Ruler length |
|
|
3.0～6.0 ＞6.0～8.0 ＞8.0 |
≤10 ≤8 ≤6 |
≤2.5 ≤2.0 ≤1.5 |
1.4 Machining
The laminated sheets should be free from crackles and scraps after being machined such as sawing, drilling, lathing and milling.
1.5 The mechanical, physical and dielectric properties of laminated sheet are as shown in Form 4
Form 4
|
No. |
Properties |
Units |
Values |
|
|
1 |
Water absorption (Nominal thickness≥1mm) |
% |
≤0.8 |
|
|
2 |
Bending strength |
At room temperature |
MPa |
≥340 |
|
150℃ |
≥170 |
|||
|
3 |
Charpy impact strength (Gap specimen, Nominal thickness≥1mm) |
kJ/m2 |
≥37 |
|
|
4 |
Insulation resistance parallel to the laminations after 24h submerged in water |
Ω |
≥1.0×108 |
|
|
5 |
Dissipation factor 1MHz |
— |
≤0.05 |
|
|
6 |
Dielectric constant 1MHz |
— |
≤5.5 |
|
|
7 |
Dielectric strength perpendicular to the laminations in transformer oil at 90℃±2℃ |
0.5 mm～1mm |
MV/m |
≥22 |
|
1.1 mm～3mm |
≥20 |
|||
|
8 |
Breakdown voltage parallel to the laminations in transformer oil at 90℃±2℃ 1min |
kV |
≥30 |
|
2 Testing methods
2.1 Appearance
Visual observation
2.2 Machining
As per Machining Methods for Insulating Laminated Products, Standard No.JB/Z141-79.
2.3 The other items are as per GB 5130-1985.
3 Inspection, marks, package, transportation and storage
3.1 The inspection items are as per Clause 1.1,1.2,1.3 and Item 2,7 of Form 4 in Clause 1.5, the items in Clause 1.1,1.2,1.3 should be checked one by one.
3.2 The laminated sheet shall be placed on underlay plates with height of more than 5cm from the floor in a clean and dry storage room where the temperature is below 40℃. It should be far from fire and heat sources and sunshine. The storage life of the laminated sheet is 18 months after leaving factory. If the laminated sheets have been stored more than 18 months, they may still be used after being tested to be qualified according to the technical requirements.
3.3 The other items are as per GB 1305-1985.
4 Remarks
4.1 The laminated sheets have different properties compared with metal. The method of JB/Z 141-1979 must be adopted when the product is machined.
4.2 Thermal conductivity of the laminated sheets is small, so high cutting speed and small depth of cut should be adopted when the product is machined.
4.3 Smell and a lot of dust are produced when the laminated sheet is machined, so measures for labor protection should be taken.