"Large diameter, non-metallic grooved sheaves" (OHTLstringingequipment.com/Stringing-Blocks--Sheaves.html target='_blank'>Stringing Blocks) are fundamental "OPGW Stringing Tools" because they minimize the risk of damage to the cable:

• Minimum Bending Radius: The larger diameter ensures the OPGW is never bent beyond its specified minimum bending radius, which is vital for preventing stress and micro-bending loss in the optical fibers.

• Fiber Protection: The grooves are precisely designed and often lined with soft, yet durable, non-abrasive materials like polyurethane or high-density nylon. This prevents scratching, crushing, or deforming the OPGW's outer metallic strands, which could indirectly impact the internal fibers.

• Smooth Operation: High-quality, sealed bearings ensure smooth rotation and low friction, reducing wear on the OPGW and minimizing pulling tension requirements.

These specialized sheaves safeguard the OPGW's structural and optical integrity throughout the stringing operation.