Varnished Fiberglass Sleeving – B Class

Varnished Fiberglass Sleeving – B Class Electrical Insulation

Varnished Fiberglass Sleeving – B Class is a flexible electrical insulation sleeving designed for moderate temperature and voltage applications. It is manufactured from braided fiberglass yarn and coated with electrical insulating varnish, followed by heat curing to improve insulation strength, surface finish, and durability.

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Varnished Fiberglass Sleeving – B Class Electrical Insulation

The fiberglass braid provides good mechanical strength and dielectric properties, while the varnish coating enhances abrasion resistance, moisture resistance, and fray resistance. Rated for Class B (130 °C) insulation systems, this sleeving is suitable for general-purpose electrical insulation where dependable performance and cost efficiency are required.

Varnished fiberglass sleeving is commonly used for lead wire insulation, internal wiring of motors, transformers, coils, electrical appliances, and general electrical equipment. Its flexibility allows easy installation, making it a practical solution for routine insulation and mechanical protection needs.

Product Details

Product Name

Varnished Fiberglass Sleeving

Insulation Class

Class B

Thermal Rating

130 °C

Base Material

Non-alkali braided fiberglass

Coating Material

Electrical Insulating Varnish

Size Range

Available in multiple inner diameters

Color Options

Natural, Red, Black, Grey (others on request)

Typical Applications

Motors, generators, transformers, wiring, cable assemblies

End Use Industries

Electrical equipment, appliances, lighting, machinery

Technical Data – Varnished Fiberglass Sleeving (B Class)

Item	Typical Specification	Reference / Remarks
Base Material	Non-alkali fiberglass yarn braided sleeving	Electrical grade glass fiber
Coating	Electrical insulating varnish (resin impregnated)	Uniform varnish coating
Insulation Class	B Class	Thermal class 130°C
Continuous Working Temperature	−30°C to +130°C	As per B-class insulation
Short-Time Heat Resistance	Up to 155°C	Limited duration
Dielectric Strength	≥ 1.5 – 2.5 kV	Depending on wall thickness
Breakdown Voltage	See product size specification	Measured after conditioning
Flame Resistance	Self-extinguishing	Non-flame propagating
Mechanical Properties	Good abrasion resistance and flexibility	Suitable for wiring protection
Chemical Resistance	Resistant to oils, greases, and common solvents	Not suitable for strong acids
Standard Colors	Natural white, yellow (other colors on request)	Custom colors available
Inner Diameter Range	0.5 mm to 25 mm	Standard production range
Standard Packing	Rolls or cut lengths	As per size requirement
Typical Applications	Internal wiring of motors, transformers, generators, electrical appliances, and general insulation protection	Low-voltage electrical insulation