• Professional Answer: At Ningbo Changshi, we manufacture two main types of professional-grade cable reel jack stands, each suited for different project needs:

  • Hydraulic Cable Reel Jack Stands: These are our most popular heavy-duty stands. They use a powerful hydraulic cylinder to effortlessly lift extremely heavy cable drums, often with a capacity of 5 tons or more. They are the ideal choice for large-scale projects involving heavy, high-voltage cables where safety and ease of use are paramount.

  • Screw-Type Cable Reel Jack Stands: These stands use a manual screw mechanism to lift the drum. They are a reliable and economical option for smaller to medium-sized cable drums where the pulling load is less demanding. They are known for their durability and low maintenance. The best choice for your project depends on the weight and size of your cable drums and the specific requirements of the job.

Professional Answer: To ensure a safe and efficient installation, you should always choose cable jack stands with the following features:

• High Load-Bearing Capacity: Ensure the stands are rated to safely support the full weight of your heaviest cable drum.

• Adjustable Height and Width: The stands should be easily adjustable to accommodate a wide range of reel diameters and widths, providing versatility for various projects.

• Robust Construction: Look for stands made from high-strength steel with a durable finish, designed to withstand rugged on-site conditions.

• Integrated Safety Mechanisms: High-quality stands, such as ours, feature safety pins and secure axle locking systems to prevent the drum from accidentally falling.

Professional Answer: While both are used for paying out cable, cable jack stands and reel rollers serve different purposes.

• Cable Jack Stands are the superior choice for heavy-duty applications and for handling very large or wide cable reels. They provide a stable, elevated platform that is crucial for keeping the cable aligned with overhead lines or underground conduits.

• Reel Rollers are single-piece platforms with rollers that the cable reel sits on. They are more suitable for lighter cable drums and for jobs where the cable reel needs to be easily moved and repositioned frequently. For most industrial and utility projects, jack stands are the go-to solution due to their superior load capacity, stability, and safety features.

Professional Answer: A professional cable pulling procedure is a systematic process designed to ensure safety and prevent costly cable damage. Our recommended procedure follows four main phases:

1. Pre-Pull Planning: This is the most critical phase. It involves calculating pulling tension, inspecting the route, and preparing all necessary safety documentation and a pulling plan.

2. Site & Equipment Setup: Securely position all equipment, including the cable drum jack stands and the hydraulic puller. The pulling rope is then fed through the route.

3. The Pull: The actual pulling of the cable begins. This phase is monitored in real-time to ensure the pulling tension and speed remain within safe limits.

4. Post-Pull Completion: Once the pull is complete, the cable is terminated, and all equipment is safely secured and prepared for the next task.

Professional Answer: Proper pre-pull planning is essential to prevent equipment failure, project delays, and most importantly, damage to expensive cables. The most necessary calculation is determining the maximum pulling tension. Factors considered include:

• Cable Weight: The total weight of the cable being pulled.

• Coefficient of Friction: The friction created between the cable and the inner surface of the conduit or stringing blocks.

• Number of Bends: Each bend significantly increases friction and tension. Our engineers at Ningbo Changshi use these calculations to recommend the precise equipment and accessories—such as specialized lubricants and cable feeders—that will ensure the pull remains safe and efficient.

Professional Answer: The setup phase is where a well-planned procedure is executed with the right tools. Each piece of equipment plays a specific role:

• Cable Drum Jack Stands: These stands safely and securely lift the heavy cable reel off the ground, allowing it to pay out smoothly without binding or toppling.

• Conduit Rollers & Guides: These are strategically placed at all bends and entry/exit points to support the cable and maintain its minimum bending radius, preventing kinking and damage to the insulation.

• Pulling Rope and Grip: A high-strength, low-stretch pulling rope is attached to the cable via a correctly sized cable pulling grip and swivel, ensuring a secure and twist-free connection.

Professional Answer: The "pull" phase is where the plan comes to life, and a focus on safety and real-time monitoring is paramount.

• Maintain a Safe Distance: All personnel should be kept out of the line of fire of the pulling rope and cable.

• Real-Time Monitoring: Our hydraulic cable pulling machines are equipped with an integrated tension recorder that provides real-time feedback on the pulling force. This allows the operator to instantly adjust the speed to prevent exceeding the cable's maximum allowable tension.

• Lubrication: A professional cable lubricant should be applied consistently to the cable as it enters the conduit, further reducing friction and making the pull smoother.

A successful low voltage (LV) cable pull requires a combination of basic hand tools and specialized equipment to ensure the job is done safely and efficiently. While many manual tools exist, for long runs or multiple cables, professional-grade equipment is necessary. The essential tools from our comprehensive supply include:

• Cable Pullers/Winch: For runs of more than a few meters, a powered cable puller or winch is a non-negotiable tool. Our hydraulic pullers are scaled down for LV applications, providing controlled force that prevents damage to the cable.

• Fish Tapes and Rods: These are indispensable for feeding a pilot rope or string through conduits and wall cavities. We offer various lengths and materials, including non-conductive fiberglass rods for safety.

• Cable Pulling Grips: Also known as cable socks, these are woven wire mesh tubes that securely attach the pulling rope to the cable. Using the correct size and type is vital to prevent the cable from slipping or being damaged.

• Cable Rollers and Guides: These accessories are used to guide the cable around corners and turns, significantly reducing friction and protecting the cable's jacket from abrasion.

While manual tools like fish tape are suitable for short, simple runs, a powered cable puller is the superior choice for a variety of low-voltage projects. You should consider a powered puller when:

• Pulling is over long distances. The sustained force required for long runs can cause significant fatigue and risk of injury to the installer.

• Dealing with tight bends or conduits. A powered puller can overcome the high friction created by multiple bends without putting a dangerous strain on the cable.

• Pulling multiple cables at once. Our machines can handle the combined weight and friction of multiple cables, ensuring they are pulled together smoothly and without crossing or kinking.

Using a powered machine ensures a consistent, monitored pull, which is safer for the crew and significantly reduces the chance of cable damage.

Protecting low voltage cables is crucial, as damage can lead to costly rework or system failure. The best way to protect cables during a pull is to use a combination of the right tools and best practices:

• Use the Right Equipment: Never exceed the cable's maximum pulling tension. Our pullers with integrated tension monitoring systems prevent over-pulling.

• Apply Cable Pulling Lubricant: A professional-grade lubricant reduces friction by up to 80%, allowing for a smoother pull at a lower tension and minimizing the risk of insulation damage.

• Use Cable Rollers and Guides: Placing rollers at strategic points, especially where the cable changes direction, prevents the cable from scraping against sharp conduit edges or other surfaces.

• Maintain the Minimum Bending Radius: Avoid sharp bends. Our cable guides and sheaves are designed to maintain the cable's required minimum bending radius, which protects the internal conductors from stress.

A fish tape is a long, flexible strip of steel or fiberglass used to route a pulling string or pilot rope through walls and conduits. It is a fundamental tool for electricians.

A fish tape is the right tool to use when:

• Installing a pulling rope for a larger machine: For long or complex conduit runs, the fish tape is the first tool you'll use to thread the pulling rope through the path.

• Working with short, simple runs: For pulling small, single wires over a short distance, a fish tape can be used manually to pull the wire directly.

• Working in occupied conduits: A non-conductive fiberglass fish tape is the safest option for pulling through conduits that may contain live wires.

Large cable pulling equipment refers to heavy-duty, high-capacity machinery specifically engineered for the installation of large conductors and power cables. These machines are typically used for projects involving:

• Overhead Transmission Lines (OHTL): Tension stringing of single, bundled, or multiple conductors over long spans.

• Extra-High Voltage (EHV) Underground Cables: Pulling heavy power cables through lengthy conduits or tunnels.

• Large-Scale Industrial Projects: Installations in power plants, substations, or renewable energy sites.

Unlike smaller tools, this equipment is designed to handle immense pulling forces, often exceeding 10 tons, while maintaining precise control to prevent damage to the costly cables.

For a one-stop supply solution, a complete set of large cable pulling equipment includes more than just the main machine. At Ningbo Changshi, we provide all the essential components for a safe and efficient operation:

• Hydraulic Puller-Tensioner: This is the heart of the system. Our hydraulic machines are trailer-mounted and powered by a diesel engine to provide the immense force and precise control required for the job.

• Hydraulic Reel Stands/Jack Stands: Heavy-duty stands or trailers used to safely lift, support, and pay out the massive, heavy reels of cable or conductor.

• Conductor Stringing Blocks/Rollers: These are strategically placed along the route to support the conductor and reduce friction as it is pulled. We offer a variety of sizes and materials for different applications.

• Pulling Rope and Swivels: A high-strength, low-stretch steel wire rope is used to connect the puller to the conductor. A specialized swivel joint is a critical accessory that prevents the rope's twisting force from damaging the conductor during the pull.

Choosing the right equipment is crucial for safety and project success. When selecting large-scale machinery, you should look for the following critical features:

• Precision Tension Control: The ability to pre-set and automatically maintain a constant pulling tension is vital for protecting conductors and avoiding exceeding their maximum allowable tension. Our hydraulic systems are designed for this exact purpose.

• High-Capacity Bullwheels: The large grooved bullwheels on our machines are lined with wear-proof MC nylon to provide maximum grip without damaging the conductor.

• Integrated Safety Features: Look for a reliable brake system, a clear tension gauge, and an automatic braking mechanism that activates in case of hydraulic pressure failure to ensure maximum operator and line safety.

• Robust and Transportable Design: The equipment must be built on a durable, trailer-mounted chassis to withstand rugged field conditions and allow for easy transportation between job sites.

Large-scale cable pulling equipment fundamentally transforms a labor-intensive and high-risk task into a controlled, safe, and efficient operation.

• Increased Safety: By automating the pull, the equipment eliminates the risk of manual lifting injuries and removes workers from the high-tension environment. Real-time tension monitoring prevents dangerous overloads.

• Superior Efficiency: These machines can complete jobs in a fraction of the time required for manual methods. They ensure a consistent pulling speed and tension, which allows for smoother installations and reduces project timelines.

• Reduced Damage and Rework: The precise control over pulling force and the use of specialized accessories like stringing blocks minimize the risk of damaging the expensive conductor or cable jacket, saving significant costs on repairs or replacement.

The choice of technique depends on the project's application. For large-scale projects, there are two primary methods:

• Overhead Tension Stringing: This is the most widely used and safest technique for installing conductors on transmission lines. It involves using a hydraulic puller-tensioner to pull the conductor while keeping it continuously suspended above the ground. This method prevents the conductor from dragging, which minimizes damage and maintains a safe ground clearance at all times.

• Underground Pulling in Conduits: For underground power cables, the technique involves a high-capacity pulling machine to draw the cable through a pre-installed duct or conduit. This technique focuses heavily on managing friction and ensuring the cable's integrity as it navigates bends and long distances.

Managing tension is the most critical aspect of large-scale cable pulling. Excessive tension can permanently damage the cable, while too little can lead to sagging or tangling. We address this with a multi-pronged approach:

• Hydraulic Tensioners: Our tensioning machines are equipped with advanced hydraulic systems that provide precise, variable tension control. This allows the operator to maintain a specific tension on the conductor throughout the entire pull.

• Friction Reduction: Using the right tools to reduce friction is a key technique. This includes the application of specialized cable pulling lubricants for underground pulls and using high-quality stringing blocks with wear-proof lining to minimize friction on overhead conductors.

• Strategic Route Planning: Our technicians use software to calculate the expected tension and to plan a pulling route that minimizes the number of sharp bends and long, straight sections, which are the main sources of friction.

A safe and efficient pull begins long before any equipment is turned on. Key pre-pull planning steps include:

• Route and Site Inspection: Conduct a thorough inspection of the entire pulling route to identify and mitigate any potential hazards, such as sharp edges, existing utilities, or difficult terrain.

• Tension and Sag Calculations: Accurately calculate the maximum pulling tension and sag requirements for the conductor. This data dictates the type of equipment, pulling rope, and accessories needed for the job.

• Equipment and Material Staging: Strategically place all equipment, including the puller-tensioner, conductor reels on jack stands, and stringing blocks, to ensure a smooth workflow and a safe "lead-in angle" for the conductor. * Safety Briefing and PPE: A detailed safety briefing for all crew members is mandatory, along with a check to ensure everyone has the correct personal protective equipment (PPE).

Safety is our top priority. The most common practices used to ensure a safe installation are:

• Real-time Tension Monitoring: All of our pullers and tensioners are equipped with a tension gauge that provides real-time feedback. This allows the operator to make instant adjustments and prevents the conductor's maximum tension rating from being exceeded.

• Maintaining Safe Distance: All non-essential personnel must be kept out of the tensioning zone and away from the pulling rope and conductor.

• Proper Grounding and Bonding: All equipment and conductors must be properly grounded to protect against electrical hazards.

• Controlled "Dead-ending": The process of securing the conductor to the end towers must be done slowly and carefully to prevent a sudden release of tension, which can cause a whiplash effect on the line.