Properties

Properties	Units	Grade
		Phenolic cotton-cloth rod						Epoxy glass fabric rod
		3721	3721-1	3722	3723	3724	3725	3840	3841	3841F
Density　　≥	—	1.25	1.25	1.28	1.26	1.28	1.26	1.75	1.70	1.75
Water absorption　≤	%	1.0	1.0	2.0 (Φ13mm)	1.3 (Φ13mm)	1.5 (Φ13mm)	1.1 (Φ13mm)	—	0.5 (Φ13mm)	0.5 (Φ13mm)
Flexural strength　≥	MPa	117.6	88.0	110.3	89.6	110.3	82.7	343.0	241.3	241.3
Tensile strength　 ≥	MPa	78.4	—	—	—	—	—	196.0	—	—
Compressive strength　　　　　 ≥	MPa	—	—	131.0	137.9	131.0	137.9	—	241.3	241.3
Insulation resistance parallel to the lamination A 　≥ D-24/2　≥	Ω	1.0×108 —	1.0×108 —	— —	— —	— —	— —	1.0×1010 1.0×107	— —	— —
Breakdown voltage parallel to laminations in transformer oil　　　　　　　　≥	KV	20±5℃ 10.0	20±5℃ 10.0	—	20±5℃ 10.0	—	20±5℃ 10.0	90±2℃ 15.0	90±2℃ 15.0	90±2℃ 15.0
Flammability	—	—	—	—	—	—	—	—	—	FV0
Colour	—	Natural	Natural	Natural	Natural	natural or black	Natural	Natural	Natural	Natural
Characteristics & Applications	—	For mechanical & electrical application.	For mechanical application, but not stronger than 3721.	Similar to NEMA's c grade	Similar to NEMA's CE grade.	Similar to NEMA's L grade.	Similar to NEMA's LE grade.	Good humidity resistance. for mechanical & electrical application.	Similar to NEMA's G-10 grade.	Similar to 3841,with good flame retardent