Production and Quality Control Process of Fiber Splice Sleeves

Production and Quality Control Process of Fiber Splice Sleeves

 Chengdu Focus Infra Materials Company is a trusted manufacturer of high-quality fiber optic splice sleeves, designed to protect optical fiber splices with reliable mechanical strength and minimal signal loss. By analyzing the material composition of fiber splice sleeves, we have developed a comprehensive production and quality control (QC) process to ensure consistency, durability, and performance in every product.

Material Composition of Fiber Splice Sleeves

A standard fiber splice sleeve typically consists of three main components:

1. Heat Shrinkable Outer Tube

• Material: Cross-linked polyolefin

• Function: Provides mechanical protection and environmental sealing after shrinkage.

2. Inner Strength Member

• Material: Stainless steel or ceramic rod

• Function: Ensures alignment and strength across the fiber splice point.

3. Hot Melt Adhesive Tube

• Material: Ethylene-vinyl acetate (EVA) or similar thermoplastic adhesive

• Function: Bonds the sleeve to the fiber and provides moisture resistance.

Production & Quality Control Workflow

1. Raw Material Inspection

Before production begins, each component undergoes strict incoming inspection:

• Polyolefin Tubes

• Check shrink ratio, clarity, diameter, wall thickness, and flexibility.

• Test temperature resistance and shrink temperature range.

• Strength Member Rods (Steel or Ceramic)

• Measure length tolerance, surface finish, and tensile strength.

• Inspect for corrosion resistance and straightness.

• Hot Melt Adhesive Tubes

• Verify melting point, viscosity, bonding strength, and uniformity.

QC Tools Used: Vernier calipers, digital micrometers, tensile testers, shrink ovens, chemical analyzers.

2. Component Preparation and Preprocessing

Each material is cut and prepared according to required sleeve dimensions (e.g., 40 mm, 45 mm, 60 mm):

• Cutting Precision: ±0.2 mm tolerance.

• Cleaning: All rods and tubes are cleaned to remove surface dust, oil, or oxidation.

• Sorting: Different sleeve types (single fiber, ribbon fiber, micro sleeves) are sorted for batch-specific production.

3. Assembly Process

This is a semi-automated process to ensure alignment accuracy:

• The ceramic or stainless steel rod is inserted into the inner adhesive tube.

• The assembly is carefully aligned within the heat-shrinkable outer tube.

• Technicians ensure concentric placement to prevent sleeve warping after shrinkage.

Key QC Points:

• Rod centered and unbent

• Adhesive tube evenly placed

• Smooth, bubble-free sleeve surface

4. In-Process Quality Checks

During production, random samples are pulled for real-time quality checks:

• Length and Diameter Verification

• Concentricity Measurement

• Assembly Integrity Test (shake and bend test to ensure components are fixed and aligned)

5. Heat Shrink Testing

Each batch is tested for shrink performance under controlled temperatures:

• Test Conditions: 110–130°C heat chamber

• Criteria:

• Complete and uniform shrinkage

• No cracking or deformation

• Good adhesion to fiber simulation rods

• No air gaps or bubbles under the sleeve

6. Tensile Strength and Adhesion Testing

Post-shrink sleeves are tested for:

• Mechanical Strength

• Sleeves must withstand pulling forces without breaking or detaching from the fiber.

• Adhesive Bonding

• Melted adhesive should maintain a strong bond to fiber in both hot and cold conditions.

Test Tools: Tensile testing machines, thermal cycling chambers

7. Final Inspection & Packaging

Before shipping, finished products undergo final checks:

• Visual Inspection: Check for scratches, dirt, inconsistent lengths, and poor adhesion.

• Batch Labeling: Each production lot is coded for traceability.

• Clean Packaging: Sleeves are sealed in anti-static bags or trays, with moisture-proof packing materials for export.

Why Our Quality Control Matters

Thanks to this materials-based inspection process, Chengdu Focus Infra Materials Company ensures that each fiber splice sleeve offers:

• ✅ Consistent shrink behavior

• ✅ High mechanical protection

• ✅ Low insertion loss

• ✅ Strong adhesion and environmental sealing

• ✅ Excellent performance across a wide temperature range

Conclusion

Our thorough understanding of fiber splice sleeve materials drives our commitment to zero-defect manufacturing. By integrating precision production and strict quality control at every step, Chengdu Focus Infra Materials Company delivers reliable, durable, and high-performance splice sleeves trusted by fiber optic installers and OEMs worldwide.

For bulk orders or custom sizes, contact our team.