China Standard Plastic Bracket Double Gold Pulley for Window and Door (ML-DD001) engine pulley

Product Description

Plastic Bracket Double Gold Pulley for Window and Door (ML-DD001)
Product Description
1.       Item No.: as shown in the picture.
2.       Material: steel/zinc/aluminum/plastic bracket + ball bearing / needle bearing wheel
3.       For some models, the height of the roller is adjustable.
4.       Color of the wheel: red, green, white, orange, etc.
5.       Application: sliding door and window, binds, rolling shutters, furniture, conveyor belt, etc.
6.       Normal packing: poly bag + outer carton

About us
Our factory is specialized in manufacturing non-standard bearing, plastic and metal pulley, bracket pulley, roller, door and window fittings, etc. Relying on a series of advanced processing equipments, skilled workers, strict inspection system, and organized management, we are able to provide good-quality products with competitive price.

Why choose us
1.       Professional experience: almost 20 years’ expenience in non-standard bearings, rollers, pulleys, and other plastic accessories for door and window.
2.       Popular over the world: over 20 market countries.
3.       Advantage: good quality with competitive price.
4.       OEM offered: technical drawings, samples or photos are needed.


For more information, please visit http://nbminli /

After-sales Service: Online Technical Support
Warranty: 2 Year
Certification: ISO, RoHS
US$ 1/Piece
1 Piece(Min.Order)


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Return&refunds: You can apply for a refund up to 30 days after receipt of the products.


What is the difference between a fixed and a swivel pulley?

Fixed and swivel pulleys are two common types of pulleys that differ in their design and functionality. Here are the key differences between these two types:

1. Fixed Pulley: A fixed pulley is a type of pulley that is mounted or attached to a fixed point, such as a beam or a ceiling. It does not move or rotate independently of its mounting point. The primary function of a fixed pulley is to change the direction of the force applied to a rope or cable. When a force is applied to the rope or cable passing through a fixed pulley, the load moves in the opposite direction. However, a fixed pulley does not provide any mechanical advantage, meaning it does not reduce the effort required to lift the load.

2. Swivel Pulley: A swivel pulley, also known as a movable pulley, is designed to rotate or swivel on a separate mounting point. It has a built-in mechanism that allows it to move independently. Unlike a fixed pulley, a swivel pulley is capable of changing both the direction and the magnitude of the force applied to the rope or cable. When a force is applied to the rope or cable passing through a swivel pulley, the load moves in the same direction as the applied force. Additionally, a swivel pulley provides a mechanical advantage by distributing the load’s weight over multiple strands of rope or cable, reducing the effort required to lift the load.

In summary, the main differences between fixed and swivel pulleys are:

– Fixed pulleys are stationary and do not move independently, while swivel pulleys can rotate or swivel on a separate mounting point.

– Fixed pulleys change the direction of the force applied to the rope or cable, while swivel pulleys change both the direction and the magnitude of the force.

– Fixed pulleys do not provide a mechanical advantage, while swivel pulleys provide a mechanical advantage by distributing the load’s weight over multiple strands of rope or cable.

Both fixed and swivel pulleys have their specific applications and can be used individually or in combination with each other to achieve desired mechanical functions in various systems and setups.


Can pulleys be part of renewable energy systems like wind turbines?

Yes, pulleys can indeed be part of renewable energy systems like wind turbines. While wind turbines primarily rely on the force of the wind to generate electricity, pulleys are used in various components to facilitate the efficient conversion of wind energy into electrical power. Here’s how pulleys can be incorporated into wind turbines:

1. Rotor and Blade Pitch Control:

Pulleys are utilized in the rotor and blade pitch control mechanism of wind turbines. The rotor consists of multiple blades that capture the wind’s energy and convert it into rotational motion. To optimize the turbine’s performance, the pitch angle of the blades needs to be adjusted based on wind conditions. Pulleys and cables are employed to control the pitch angle, allowing the blades to be positioned at the optimal angle to maximize power output. The pulley system enables precise and synchronized blade adjustment, ensuring efficient wind capture.

2. Generator System:

In wind turbines, pulleys are also utilized in the generator system. The rotational motion of the turbine’s rotor is transferred to the generator through a series of mechanical components, including pulleys and belts or gears. The pulleys help to increase or decrease the rotational speed and torque as needed to match the generator’s requirements. This mechanical advantage provided by the pulleys ensures that the generator operates at its optimal speed, enhancing the efficiency of electricity generation.

3. Lifting and Maintenance Systems:

Pulleys are often incorporated into the lifting and maintenance systems of wind turbines. Wind turbine components, such as the nacelle (housing the generator and other equipment) and the rotor blades, are large and heavy, requiring periodic inspection, repair, and replacement. Pulley systems are employed to lift and lower these components during maintenance activities. The pulleys, along with cables and hoists, allow for controlled and safe handling of the heavy parts, enabling efficient maintenance and minimizing downtime.

4. Access Systems:

In larger wind turbines, pulleys are utilized in access systems that provide safe and efficient access to various parts of the turbine, including the nacelle and the rotor blades. Climbing systems or platforms equipped with pulleys allow technicians to ascend or descend the turbine structure, providing easy access for inspection, maintenance, and repairs. Pulleys facilitate the movement of personnel and equipment, ensuring the safety and efficiency of wind turbine operations.

By incorporating pulleys into these different aspects of wind turbines, renewable energy systems can benefit from increased efficiency, improved maintenance procedures, and enhanced safety measures. Pulleys contribute to the overall performance and reliability of wind turbines, enabling the harnessing of wind energy for clean and sustainable electricity generation.


What is a pulley, and how does it function in mechanical systems?

A pulley is a simple machine consisting of a grooved wheel and a rope, cable, or belt that runs along the groove. It is used to transmit force and motion in mechanical systems. Here’s a detailed explanation of how a pulley functions:

1. Mechanical Advantage: The primary function of a pulley is to provide mechanical advantage. By changing the direction of the force applied and distributing it over multiple segments of the rope or belt, a pulley system allows for easier lifting or moving of heavy loads. The mechanical advantage gained depends on the number of pulleys used in the system.

2. Force Transmission: When a force is applied to one end of the rope or belt, it creates tension that causes the pulley to rotate. As the pulley turns, the force is transmitted to the load attached to the other end of the rope or belt. This force transmission allows for the movement and manipulation of objects in mechanical systems.

3. Directional Change: One of the key functions of a pulley is to change the direction of the applied force. By redirecting the force along a different path, a pulley system enables the operator to exert force from a more convenient or advantageous position. This directional change is particularly useful in situations where the force needs to be applied vertically, horizontally, or at an angle.

4. Speed and Torque Conversion: In addition to changing the direction of force, pulleys can also be used to convert speed and torque in mechanical systems. By varying the size of the pulleys or using pulleys of different diameters, the rotational speed and torque can be adjusted according to the requirements of the system. This speed and torque conversion allows for the optimization of power transmission and the matching of different rotational speeds between input and output components.

5. Multiple Pulley Systems: Pulleys can be combined in systems to achieve increased mechanical advantage or to create complex motion patterns. In systems with multiple pulleys, such as block and tackle arrangements, the load is distributed over several segments of rope or belt, further reducing the effort required to lift heavy objects. These systems are often used in cranes, elevators, and other applications where heavy lifting is necessary.

6. Fixed and Movable Pulleys: Pulleys can be categorized as fixed or movable. A fixed pulley is attached to a stationary structure, and its main function is to change the direction of force. A movable pulley, on the other hand, is attached to the load being moved and moves with it. Movable pulleys provide mechanical advantage by reducing the effort required to lift the load.

7. Belt and Rope Pulleys: Pulleys can have different designs depending on the application. Belt pulleys typically have a grooved surface to grip and guide belts, while rope pulleys have a smooth surface to minimize friction and prevent rope wear. The choice between belt and rope pulleys depends on factors such as load requirements, operational environment, and desired efficiency.

Overall, a pulley is a versatile mechanical device that functions as a force multiplier, directional changer, and speed/torque converter in mechanical systems. Its ability to provide mechanical advantage, change force direction, and facilitate complex motion patterns makes it an essential component in various applications, including lifting, transportation, and power transmission.

China Standard Plastic Bracket Double Gold Pulley for Window and Door (ML-DD001)   engine pulleyChina Standard Plastic Bracket Double Gold Pulley for Window and Door (ML-DD001)   engine pulley
editor by CX