Trenchless technology, such as Horizontal Directional Drilling (HDD), is a method of installing underground utilities without the need for open-cut trenching. This is particularly valuable in congested areas where cutting through roads, sidewalks, and existing infrastructure is not feasible. The process involves drilling a pilot hole along a predetermined path and then reaming it to a larger diameter before pulling the cable-carrying conduits into place.

Ningbo Changshi provides essential equipment that directly supports these trenchless projects, including:

• Cable Pulling Winches: Powerful winches with precise tension control are critical for pulling heavy and long lengths of conduit and cable through the drilled holes.

• Swivels and Pulling Grips: These are used to securely attach the cable to the pulling winch and to ensure the cable does not twist during the pullback operation.

• Hydraulic Reel Stands: These stands are used to safely manage the large, heavy cable drums, ensuring a smooth, controlled feed of the cable into the conduit.

Our Professional Answer: For cable installation in tight or confined spaces, specialized, compact equipment is essential. Our product line includes a range of tools designed for this purpose, such as:

• Compact Cable Rollers: These rollers are designed with a small footprint to fit within narrow trenches and manholes, ensuring smooth cable feeding without damage.

• Lightweight Cable Winches: Portable and powerful, these winches are built for use in spaces where heavy machinery is not feasible, providing the necessary pulling force for longer cable runs.

• Micro-Trenching Buckets and Attachments: These specialized attachments for excavators create the precise, narrow trenches required for micro-trenching, minimizing excavation volume and speeding up the restoration process.

At Ningbo Changshi, we understand that selecting the right conductor is crucial for a successful project. For distribution lines, the primary choices are AAC (All Aluminum Conductor), AAAC (All Aluminum Alloy Conductor), and ACSR (Aluminum Conductor Steel Reinforced).

• AAC is made of pure aluminum strands and is highly conductive. Its light weight and excellent corrosion resistance make it an economical choice for urban areas with short spans and where high mechanical strength is not a primary concern.

• AAAC uses a high-strength aluminum alloy, giving it a better strength-to-weight ratio and improved sag performance compared to AAC. It also has superior corrosion resistance, making it ideal for coastal and industrial environments.

• ACSR is a composite conductor with an outer layer of aluminum strands and a central steel core. This design offers a high tensile strength, allowing for longer spans and reduced sag. It's a dependable and economical solution for projects requiring high mechanical strength and reliability.

Answer: The widespread use of aluminum conductors like ACSR is due to a combination of their physical and economic advantages. Aluminum is lightweight and highly conductive, making it an efficient material for carrying electrical current. When combined with a galvanized steel core in an ACSR conductor, the product offers exceptional tensile strength, which allows for longer spans between support towers. This reduces the number of towers needed for a project, significantly lowering both material and installation costs. Additionally, the larger diameter of ACSR conductors helps to reduce electrical losses from the corona effect on high-voltage lines.

Answer: While ACSR is a versatile choice, we often recommend AAAC for specific applications where its characteristics offer a significant advantage. AAAC conductors have better corrosion resistance than ACSR, which makes them the superior choice for projects in highly polluted industrial areas or coastal regions with a high salt content in the air. Furthermore, AAAC provides better sag performance and a higher strength-to-weight ratio than ACSR, which can lead to longer spans and cost savings on support structures.

Professional Answer: A complete tension stringing setup requires a coordinated system of specialized equipment. The core components are a hydraulic puller and a hydraulic tensioner. The puller provides the controlled pulling force to move the conductor, while the tensioner applies a constant back-tension to keep the conductor off the ground. These are complemented by a variety of essential tools and accessories, including:

• Conductor stringing blocks: To guide the conductor along the towers.

• Reel stands: To safely hold and feed the conductor drums.

• Pulling rope: The high-strength steel or synthetic rope used by the puller.

• Anti-twist swivels: To prevent torsion from transferring to the conductor.

• Running boards and conductor grips: For connecting multiple conductors or ropes securely.

• Answer: These are key pieces of equipment in overhead line stringing, each with a distinct function.

  • A hydraulic puller is a machine used to pull the conductor (wire) along the overhead line. It applies a strong, constant force to a steel pilot rope, which in turn pulls the conductor through the stringing blocks.

  • A hydraulic tensioner is used to maintain a specific tension on the conductor as it is being unspooled from the reel. This prevents the conductor from sagging and touching the ground or other obstacles, ensuring a smooth and controlled stringing process.

  • A hydraulic puller-tensioner is a versatile, all-in-one machine that can perform both pulling and tensioning functions. This is particularly useful for complex projects where the same equipment needs to be used for both pulling and tensioning phases, offering greater flexibility and efficiency on the job site.

  
  

Answer: A successful stringing project requires a range of specialized tools and accessories in addition to the main machines. Essential items include:

• Stringing Blocks (Running Blocks): These are used to support the conductor and allow it to run smoothly along the transmission tower arms.

• Anti-Twisting Braided Steel Wire Rope: This is used as the pulling rope. Its braided structure prevents twisting, which is crucial for maintaining stability during stringing.

• Conductor Grips (Come-Alongs): These clamps are used to secure the conductor, either for pulling or for adjusting sag.

• Swivel Joints: These are placed between the pulling rope and the conductor to prevent rotational forces from twisting the conductor.

• Hydraulic Crimping Tools (Compressors): Used for connecting conductor ends and applying compression to joints.

• Digital Dynamometers: These are used to accurately measure and monitor the pulling force or tension on the line, ensuring safety and compliance with project specifications.

• Reel Stands and Reel Winders: Equipment designed to safely hold conductor reels and manage the unspooling or winding of ropes and conductors.

Answer: Safety is paramount in all power line projects. Key safety precautions include:

1. Proper Equipment Anchoring: Both the puller and tensioner must be rigidly anchored on all sides to prevent movement during operation.

2. Regular Equipment Inspection: All tools, tackles, and equipment should be inspected regularly by a competent person. Damaged equipment must be removed from use immediately.

3. Use of Personal Protective Equipment (PPE): All workers and supervisors must wear appropriate PPE, including safety helmets, gloves, and full-body harnesses with double hooks.

4. Maintaining Clearances: The conductor should be kept clear of the ground and all obstacles to prevent damage and avoid contact with energized circuits.

5. Operational Procedures: Always follow the manufacturer's operational manual. Operators must be trained and certified to use the specific equipment.

Answer: Proper maintenance is crucial for the longevity and reliable performance of your equipment. Routine maintenance for hydraulic pullers and tensioners should include:

1. Greasing: Regularly grease all rotating and moving parts to ensure smooth operation and prevent wear.

2. Hydraulic System Checks: Periodically check hydraulic fluid levels and inspect all hoses and connections for leaks or damage.

3. Bullwheel Inspection: For tensioners, regularly check the bullwheels. We offer models with replaceable nylon sectors, making maintenance and replacement straightforward.

4. Anchor Point Inspection: Before each use, inspect all anchor points for signs of stress or damage.

Answer: Underground cable laying requires specialized tools to ensure a smooth and efficient installation. The key equipment includes:

1. Cable Pullers/Winchers: These are robust machines used to pull cables through ducts or trenches. Our hydraulic pullers are designed for smooth, controlled pulling with a visual display of the pulling force.

2. Cable Drum Jacks/Trailers: Used to lift and handle heavy cable drums safely, ensuring they can be unwound with controlled tension.

3. Cable Rollers: Placed in trenches and manholes to support the cable and reduce friction as it is pulled, protecting the cable's surface.

4. Cable Socks & Grips: Securely connect the pulling rope to the cable, distributing the tension evenly to prevent damage to the cable.

5. Duct Rodders: Used to pull pilot lines through underground conduits before the main cable is installed.

At Ningbo Changshi, we provide a full range of high-quality equipment for your underground cable laying needs, ensuring precision and safety.

Answer: Underground cable laying requires specialized tools to ensure a smooth and efficient installation. The key equipment includes:

1. Cable Pullers/Winchers: These are robust machines used to pull cables through ducts or trenches. Our hydraulic pullers are designed for smooth, controlled pulling with a visual display of the pulling force.

2. Cable Drum Jacks/Trailers: Used to lift and handle heavy cable drums safely, ensuring they can be unwound with controlled tension.

3. Cable Rollers: Placed in trenches and manholes to support the cable and reduce friction as it is pulled, protecting the cable's surface.

4. Cable Socks & Grips: Securely connect the pulling rope to the cable, distributing the tension evenly to prevent damage to the cable.

5. Duct Rodders: Used to pull pilot lines through underground conduits before the main cable is installed.

At Ningbo Changshi, we provide a full range of high-quality equipment for your underground cable laying needs, ensuring precision and safety.