Q: What certifications and test reports come with your machines?

A: Machines are factory load-tested; CE/ISO paperwork is available and third-party inspection (FAT) can be arranged on request.

OPGW installation requires specialized equipment to protect the delicate optical fibers within the cable. While the basic process is similar to stringing standard conductors, key differences include:

• Specialized Grips: OPGW requires non-damaging, soft-lined grips (come-along clamps) that distribute pressure evenly to avoid crushing the fibers.

• Grooved Sheaves: Stringing blocks (pulleys) must have a groove profile specifically designed for the diameter of the OPGW cable and be made of materials like nylon or polyurethane to prevent abrasion.

• Controlled Tension: A hydraulic puller-tensioner with highly sensitive controls is essential. It must maintain a smooth, constant tension to avoid sudden jerks or excessive sag that could damage the optical fibers.

• Swivels: High-quality, anti-twisting swivels are crucial to prevent the OPGW from rotating during the pulling operation, which can cause internal fiber damage.

At Ningbo Changshi, we offer complete OPGW stringing solutions, including specialized puller-tensioners, nylon-sheave stringing blocks, and appropriate swivels designed to ensure the integrity of your fiber optic network.

This is an excellent and crucial question for international projects. Our hydraulic puller-tensioners are engineered for global deployment and feature:

• High-Altitude Performance: For high-altitude projects where air density is lower, we equip our machines with powerful, often turbocharged, diesel engines (e.g., Cummins, Deutz) that are calibrated to perform efficiently with less oxygen. The hydraulic cooling systems are also oversized to dissipate heat effectively in thin air.

• Tropical/Hot Climate Resilience: Our equipment features advanced cooling systems with large-capacity radiators for both the engine and hydraulic oil. This prevents overheating during continuous operation in high ambient temperatures, ensuring consistent performance and protecting hydraulic components.

• Cold Climate Operation: We offer optional packages for cold climates that include engine block heaters, hydraulic oil warmers, and specialized fluids that maintain low viscosity at sub-zero temperatures, ensuring reliable start-up and operation.

We work directly with clients to understand their project's environmental conditions and recommend the optimal machine configuration.

Long-span crossings present unique challenges requiring precision and specialized techniques. Best practices that our equipment supports include:

• Pilot Wire Installation: Often, a light pilot rope is first installed using a drone or a pilot helicopter. This rope is then used to pull in progressively larger pulling ropes, and finally the conductor.

• Sag and Tension Monitoring: Utilizing a dynamometer and sag scopes (or modern digital GPS-based systems) is critical. Our hydraulic pullers provide real-time tension readouts to ensure the conductor is not over-stressed.

• Use of Multiple Tensioners/Brakes: For exceptionally long or heavy conductors, a multi-reel tensioning system or braking systems on the pulling side might be employed to manage the immense forces involved.

• Communication: Clear and constant communication between the puller operator, tensioner operator, and spotters along the span is paramount for safety and success.

Our high-capacity pullers (8 tons, 10 tons, and higher) and multi-conductor tensioners are specifically designed to provide the power and control needed for these demanding crossing projects.