Fiberglass Insulation Sleeves

Fiberglass Sleeve Manufacturer in India | Fiberglass Insulation Sleeves for Wires & Cables

Fiberglass sleeve manufacturer in India. Insulation sleeve for wire, electrical insulation sleeve & heat resistant fiberglass sleeve. Pan-India supply.

Fiberglass Sleeve – India’s Trusted Insulation Sleeve for Wire and Cable Protection

The fiberglass sleeve is an intricate braided protective cover that is made for protecting wires, cables, and electrical equipment from heat, abrasion, chemical corrosion, and voltage damage. Harnawa Insulations is one of the topmost fiberglass sleeve manufacturing companies in India which has an entire array of certified fiberglass sleeves for industrial, electrical, automotive, and OEM purposes.

Each of our sleeves is made using high-quality glass fiber yarns through advanced braiding technologies providing uniform wall thickness, dimensional stability, and dielectric strength in each of our sleeves. Be it for use as wire insulation in transformer windings, automotive harnesses requiring heat resistance, or for use in furnaces and heaters, we provide a wide variety of fiberglass sleeve products that meet the rigorous industrial and export requirements.

Being one of the topmost fiberglass sleeve manufacturers in India, we have the capability of doing in-house braiding, coating, and heat treatments in one place.

What Is a Fiberglass Insulation Sleeve?

Fiberglass insulating tubing is a tubular braiding made of fiber glass that is used on wires, cables, terminals, and bus bars for protection from heat, chemicals, and mechanical damage. At the same time being both an electrical insulation tubing and fiberglass heat tubing, it becomes a vital element for motor winding, transformers assembly, cabling, and appliance wiring in almost all industries using electrical appliances.

Unlike plastic extruded tubing, fiberglass tubing is made up of continuous fiber glass yarns. Thus, it has the following advantages over plastic tubing:

• Thermal flexibility — it bends without cracking around coils, corners, and tight harness routing, something that cannot be done with rigid extruded tubing
• Memory properties — due to the braiding construction, the material stretches to accommodate over connectors and terminations
• Base material non-melting — glass fibers do not melt or drip when compared to many thermoplastic sleeve materials

Since glass fibers without any kind of coating on them can be fairly brittle and fragile, various treatments are applied to the braided base, which gives rise to the various grades that will be mentioned below.

How Fiberglass Sleeves Are Manufactured

Understanding the manufacturing process helps explain why coating and grade selection matters so much for performance:

1. Fiberglass Yarn Selection – The E-glass (Electrical Grade) or C-glass (Chemical Grade) fiberglass yarn is chosen according to its expected dielectric and chemical resistance properties. For more information, please refer to our Fiberglass Yarn product line that offers the raw yarn for this production process.
2. Braiding – The yarn is braided in special braiding machines in order to make a uniform tubular sleeve.
3. Coating/saturation – Depending on the application, the braided sleeve is impregnated by silicone rubber, acrylic resins, polyurethane, PVC, or insulating varnish or left uncoated and then heat treated.
4. Heat Treatment/Curing – In case the sleeve is impregnated, the curing process takes place at a definite temperature in order to attach the coating to the fiberglass substrate. If the sleeve is not coated, it undergoes heat treatment in order to burn the organic sizing in it.
5. Quality Testing – Dielectric strength, thermal stability, and uniformity of dimensions are tested according to ISO standards, UL specifications and internal quality requirements before shipment.

Types of Fiberglass Sleeves We Manufacture

1. Coating-Based Fiberglass Sleeves

Uncoated / heat-treated fiberglass sleeveNone (heat-treated)Extreme high-temperature use where organic coatings degradeHTG heat-treated sleeveNone (special heat treatment)Very high temperature dielectric applicationsHeat reflective sleeveAluminum coatingRadiant heat shielding for hoses, pipes, and cable bundlesFire sleeve / pyro sleeveSilicone rubberExtreme heat up to 1600°C, molten splash protectionKevlar / aramid sleeveNone / braided aramidHigh-strength, cut and abrasion-resistant protection

2. Temperature Class-Based Insulation Sleeves

3. Voltage Grade-Based Sleeves

• A-Grade – 7kV – High dielectric strength for heavy electrical applications
• B-Grade – 4kV – Conventional industrial insulation
• C-Grade – 1.5kV – Low electrical applications

Available voltage ratings also include 1500V, 2500V, 4000V, and 7000V fiberglass sleeving, selected according to the working voltage of the wiring system being insulated.

4. Specialty and Application-Specific Sleeves

• Fiberglass spark plug cable sleeve – Cable insulation for spark plug cables in automobiles
• Thick wall fiberglass cable sleeve – Cable sleeve providing added mechanical protection and thickness
• Expandable polyester braided sleeve – Light weight cable bundling and harness protection sleeve
• PTFE/Teflon cable insulation sleeve – High frequency cable and chemically harsh environment application
• Heat shrinkable cable insulation sleeve – Cross linked polyolefin cable insulation sleeve

Key Features of Braided Fiberglass Sleeve

• Dielectric strength is high to provide reliable electrical insulation sleeve performance
• Thermal resistant qualities allow for reliable use as a fiberglass heat sleeve
• Resistant to abrasion, chemicals, and corrosion
• Flexible, lightweight, and easy to install over wires, cables, and harnesses
• Properties that make it flame retardant, ideal for use in industrial settings
• Uniform wall thickness in all manufactured batches
• Customized sizes, coatings, and voltage ratings available upon request
• Durable performance even under continuous thermal cycles

Applications of Fiberglass Insulation Sleeves

Fiberglass insulation sleeves are used wherever wiring needs protection from heat, abrasion, or electrical stress, including:

• Insulation of electrical wires and cables – General insulation of electrical wires for use in panels, control cabinets, and switch gears
• Construction of transformer and coil – Insulation of windings and protection of leads used in transformers
• Construction of motors – Insulation of stator and rotor leads
• Construction of generators – High-temperature insulation of windings and leads
• High temperature industrial applications – Kilns, furnaces, and industrial process heating systems
• Electric cars – Insulation of batteries and leads used in motors
• Capacitor construction – Insulation of leads used internally
• Automotive wire protection – Electrical wire insulation in the engine bay and protection of spark plugs
• Aerospace and defense – Heat and abrasion resistant electrical wire protection systems
• Industrial machinery and equipment – General wire protection systems

Fiberglass Sleeve vs. Other Insulation Sleeving Materials

Why Choose Harnawa as Your Fiberglass Sleeve Manufacturer in India?

As an established fiberglass sleeve manufacturer in India, Harnawa Insulations is built on consistent product quality, technical support, and dependable supply across both domestic and export markets.

• End-to-end manufacturing facility for coated sleeves, uncoated sleeves, and specialized sleeves
• In-house braid, coating, and heat treatment operations to ensure quality control
• Custom sleeve size, wall thickness, coatings, and voltage/temperature grading are possible
• Competitive pricing for large orders and OEM applications
• Quality assurance tests conducted during each stage of production
• On-time deliveries all over India and internationally
• Certified quality systems like ISO 9001:2015, UL, CE, RoHS, and REACH compliance
• Technical support for choosing the right grade of sleeve for your application

We are reputed manufacturers of fiberglass sleeves, who supply our products to OEMs, transformer makers, motor makers, panel makers and industrial distributors in India, serving one-time special technical requirements and repeat bulk orders alike.

For more information on our full line of Fiberglass Insulation Sleeves, please refer to our datasheets or contact our technical sales team.

How to Choose the Right Fiberglass Sleeve for Your Application

Selecting the correct sleeve comes down to three key questions:

1.What is the maximum operating temperature?

fire sleeve according to the maximum temperature that the sleeve is going to be exposed to.

2.What is the working voltage?

Match your sleeve material with voltage grades A/B/C or specific kV depending on the dielectric need of the circuit you are insulating.

3.What is the operating environment?

Exposure to moisture, chemicals, abrasion, or flexibility needs determine if your application is suited for silicone, PVC, PU, acrylic, or heat treated sleeve.

If you’re unsure which grade applies to your application, our technical team can recommend the correct heat resistant fiberglass sleeve based on your operating conditions and compliance requirements.

Related Insulation Materials from Harnawa

Fiberglass sleeves are just one part of a complete electrical insulation system. Harnawa also manufactures and supplies:

• Aramid Papers – Nomex-based insulation papers for motor and transformer winding
• Insulation Tapes (High Temperature) – Aramid, polyester, and polyimide tapes for demanding thermal environments
• Polyimide Film – High-performance dielectric film for Class H insulation systems
• Laminated Insulation Paper Composites – NMN, NHN, and AHA laminates for slot and phase insulation
• Fiberglass Yarn – E-glass and C-glass yarns used as the raw material in our braided sleeve manufacturing
• Insulating Varnishes and Thinner – Elantas varnishes used for winding impregnation and varnished sleeve coating

For our complete product portfolio, visit our Electrical Insulation Materials Manufacturer in India homepage.

Frequently Asked Questions

1.What is the use of fiberglass sleeves?

Fiberglass sleeves are used for thermal, abrasion, and electrical protection of wire and cable in motors, transformers, generators, and industrial wiring systems.

2.Which fiberglass sleeve is suitable for high temperatures?

The silicone coated and heat treated fiberglass sleeves can be used at high temperature up to grade X (more than 500°C) with stable performance from Class H (200°C).

3.What is the difference between coated and uncoated fiberglass sleeves?

Coated sleeves (with Silicone, Acrylic, PU, PVC, Varnish coating) provide additional protection against moisture, mechanical, and dielectric problems while uncoated heat treated sleeves are employed at very high temperatures where coatings cannot sustain the operating temperature.

4.Are fiberglass sleeves available in customized sizes?

Yes, Harnawa provides custom diameters, wall thicknesses, coating, voltage and temperature grading depending upon your requirement.

5.Are various voltage graded insulation sleeves provided by you?

Our company provides fiberglass insulation sleeves with various voltage grading from 1500v up to 7000v. Grade A (7kv), Grade B (4kv), Grade C (1.5kv).