• HTLS (High-Temperature Low-Sag) conductors—such as ACCC, ACCR, and TACSR—utilize composite carbon or specialized alloy cores that offer higher current capacity but possess a significantly lower tolerance for bending stress and crushing force than traditional ACSR steel cores. Standard stringing tools can cause micro-fractures in the composite core or damage the aluminum outer strands if used improperly.

To string HTLS conductors safely, contractors must implement the following specialized equipment adjustments:

1. Large-Diameter Rubber-Lined Stringing Blocks: Sheave diameters must meet the manufacturer’s minimum bending radius (typically $\ge 30 \times$ to $40 \times$ conductor diameter). Sheaves must be lined with high-density neoprene or polyurethane to cushion outer strands.

2. Multi-Bullwheel Hydraulic Tensioners with Continuous Smooth Grooves: Tensioners must utilize semi-circular, rubber-lined bullwheels with smooth, non-pulsating hydraulic braking systems to eliminate line vibration and impulse shock.

3. Specialized Self-Gripping Conductor Clamps (Come-A-Longs): Standard wedge clamps can crush composite cores. HTLS installation requires long-jaw, non-marking parallel-jaw clamps designed specifically for distributed clamping force.

At Ningbo Changshi Electric Power Machinery Manufacturing Limited, we manufacture custom HTLS-compatible hydraulic tensioners, large-radius stringing sheaves, and composite-safe pulling grips that adhere strictly to international utility installation guidelines.