Tag Archives: sheaves

China Custom Cast Iron V- Belt Pulley Sheaves with Taper Lock or Pilot Bore SPA Spb Spc Spz near me manufacturer

Product Description

product description

support customized

 

 

V belt pulley specifications

  •  European standards : 

    a) V-belt pulley for taper bushing: SPZ, SPA, SPB, SPC    

    b) Adjustable speed V-belt pulleys and variable speed pulleys              

    c) Flat belt pulleys and conveyor belt pulleys

  •  American standard:  

   a) Sheaves for taper bushing: 3V, 5V, 8V     

   b) Sheaves for QD bushings: 3V, 5V, 8V    

   c) Sheaves for split taper bushing: 3V, 5V, 8V    

   d) Sheaves for 3L, 4L or A, and 5L or B belts: AK, AKH,2AK, 2AKH, BK,  BKH,2BK, 2BKH, 3BK    

   e) Adjustable sheaves: poly V-pulley, multi-pitch H, L, J, K and M

  •   Bore: pilot bore, finish bore, taper bore, bore for QD bushing
  •   Parts can be made according to drawings and/or samples
  •   OEM service is welcomed

PACKING

Packaging
                      
    Packing  

 

We use standard export wooden case, carton and pallet, but we can also pack it as per your special requirements.

OUR COMPANY

ZheJiang Mighty Machinery Co., Ltd. specializes in offering best service and the most competitive price for our customer.

After over 10 years’ hard work, MIGHTY’s business has grown rapidly and become an important partner for oversea clients in the industrial field and become a holding company for 3 manufacturing factories.

MIGHTY’s products have obtained reputation of domestic and oversea customers with taking advantage of technology, management, quality and very competitive price.

Your satisfaction is the biggest motivation for our work, choose us to get high quality products and best service.

OUR FACTORY

FAQ

Q: Are you trading company or manufacturer ?

A: We are factory.

Q: How long is your delivery time?

A: Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.

Q: Do you provide samples ? is it free or extra ?

A: Yes, we could offer the sample for free charge but do not pay the cost of freight.

Q: What is your terms of payment ?

A: Payment=1000USD, 30% T/T in advance ,balance before shippment.

We warmly welcome friends from domestic and abroad come to us for business negotiation and cooperation for mutual benefit.To supply customers excellent quality products with good price and punctual delivery time is our responsibility.

Types of pulleys and their advantages and disadvantages

There are several types of pulleys. Learn the basic equations of the pulley system. Then learn about the different uses for pulleys. The disadvantages of using pulleys will be covered. Knowing these, you can buy the pulley that suits your needs. Here are some of the best pulley types and their pros and cons.
pulley

Basic equations of pulley systems

A pulley system is a mechanism that allows 2 blocks of a certain mass to be connected by a taut rope. The acceleration of each block is the same in magnitude and direction. The external force acting on each block is the weight of the block (10g) and the tension in the string. The tension between the 2 blocks is the total tension and the force acting on the pulley is the weight of the 2 blocks.
This simple mechanism uses 2 simple equations to explain how the system works. First, the mass of the weight on both sides of the pulley must be the same. When the weight is forced to move, the rope tightens and the second pulley descends. The weight is also attached to the second pulley and must be the same distance as the first pulley. This will result in a speed ratio of 2 times the distance covered by the first pulley.
Second, we have to calculate the force required to lift the object. The lower mass is supported by a wire configuration passing through all pulleys, while the uppermost pulley is used to apply the force. The lower block is used to support the weight. The applied force needs to travel a distance nx to move the weight. This distance, called MA, can be written as:
Once we have gathered the necessary information, we can apply the calculations to the pulley system. We can also use the Mechanical Advantage Calculator to calculate the force on the anchor. To do this, we must apply a force to the load as well as to the pulley itself. Using this equation, we can calculate the force required by the load to lift the load.
pulley

Types of pulleys

There are 3 basic types of pulleys: movable, fixed and compound. Both types of pulleys translate the force applied to them. The ideal mechanical advantage of pulleys is two. This is because a single movable pulley only doubles the force, whereas a compound pulley doubles or triples the force. This type of pulley is often used with other types of pulleys.
Movable pulls move with the weight of the load, and the force pulling them increases on the lift side. They are often found in utility elevators and construction cranes. These systems are very simple, inexpensive and quiet to use. The force required to lift the object depends on the mechanical advantage of the system. The 2 most common types of pulleys are listed below. Let’s take a closer look at each one.
V-shaped pulleys are used in vehicles and electric motors. These pulleys require a “V” belt to function properly. Some have multiple “V” grooves to avoid slipping. They are used in heavy duty applications to reduce the risk of power slip. These pulleys also have more than 1 “V” groove. V-belt pulleys are commonly used in vehicles and electric motors.
Composite pulleys are made from more than 1 type of cable or rope wrapped around the wheel. They can be fixed or hinged and are usually made of stainless steel or bronze. Composite pulleys have multiple layers and can be a single unit or many different components. There are 3 main types of pulleys: fixed pulleys and composite pulleys. These are the most common types. Almost every type of pulley is used for some type of application.
Fixed pulleys have 1 advantage over movable pulleys: they change direction as the weight of the load increases. They are typically used in heavy construction equipment. Gun tackles, patio tackles, and stationary tackles are examples of equipment that use a pulley mechanism. These devices are very common and can be found on most modern construction sites. They provide great convenience for lifting large loads.

application

What are the applications of pulleys? Simply put, a pulley is a mechanical device that transforms a difficult task into an easier one. It consists of ropes and pulleys. It is usually used to lift objects. Usually, people wrap a rope around a pulley and pull up to lift the object. One disadvantage of using pulleys is that they require the same force as lifting the object directly.
One of the most popular applications of pulleys is lifting heavy objects. They help people pull up heavy objects and blocks. The system can also be used in seeders, lifts, grinders, etc. Other applications include raising flags, loading cargo, pulling curtains and rock or mountain climbing. Students can learn about the various uses of pulleys and the physics behind them.
Pulleys can be made of many different materials, depending on the application. Some are movable, which means they move with the object they are used to lift. This pulley system can be made of nylon, wire rope or fiber material. The best part about these systems is that they are easy to install and maintain. For a better grasp, use the guide or video tutorial to learn more about the pulley system and how it works.
Tapered pulleys are common in paper mills. They are high-quality pulleys that transmit power to connected parts. They can be dynamic or static and have different balances. Because pulley systems are highly customized, most industrial applications require systems designed specifically for specific applications. In this way, the system is safe, simple and inexpensive. The benefits of this design are endless.
The most common use of pulleys is for motor drives. They are used to minimize noise by applying force to the shaft to reduce the workload. They are also less expensive than gears and do not require lubrication. Furthermore, they can change the direction of the applied force. They are also less expensive than gears and are often used with other components. A screw is a cylindrical member with helical ribs used to connect something.
pulley

shortcoming

Although the pulley system makes it easier to move heavy objects, it still has some drawbacks. When using a pulley system, you must remember that the force required to lift the weight increases with the number of cycles. In addition, the distance between the puller and the heavy object increases, which may lead to accidents. Also, moving heavy objects can be tricky if the rope slips. Pulley systems are not very expensive and can be easily assembled. However, it does require a lot of space.
First, it is not efficient. Besides being inefficient, pulleys produce different forces at different speeds. Fixed pulleys use more force than the load, while movable pulleys move with the load. A movable pulley requires less force than a fixed pulley, but the combined system travels a long distance. Therefore, this method is not as efficient as the fixed method.
Pulleys are not only used in industrial processes. You can see them in various places in your daily life. For example, large construction cranes use pulleys to lift heavy loads. Even flagpoles, blinds, clotheslines, ziplines, motors and climbing equipment use pulleys. Still, despite their advantages, the disadvantages are not too serious.
Another disadvantage of the pulley is its wear and tear. While a pulley’s housing is theoretically infinite, its bearings and locking components typically wear out over time. To overcome this problem, a new bearing and locking assembly can be installed. No need to replace the housing and shaft, the entire assembly can be re-bonded and painted to replicate the original look. Alternatively, the pulley can be replaced with a new housing and shaft.
Using pulleys can also reduce the advantage of pulleys. On the other hand, interception and tackle is a system in which 2 pulleys are connected to each other using ropes. Unlike pulleys, pulley pulley systems can be adjusted in the direction of travel and can move heavy loads up to 4 times their force when used in hydraulic lifts.

China Custom Cast Iron V- Belt Pulley Sheaves with Taper Lock or Pilot Bore SPA Spb Spc Spz     near me manufacturer China Custom Cast Iron V- Belt Pulley Sheaves with Taper Lock or Pilot Bore SPA Spb Spc Spz     near me manufacturer

China Professional Design Cable Rollers Bearings Cable Sheaves and Pulleys near me factory

Product Description

Hoisting nylon pulley block with hook Cable Pulling Roller
 

Cable roller is widely used in engineering machinery, electric power,petroleum, mining,coal,metallurgy, paper making,construction,port,cable and oher industries, cable tunnels show exhibition place or on the ground put the extension cable and wire release. The product is divided into single -round and three, non- fragile cables. They run maintennance-free on dirt and duct-proof bearings. The robust steel frames are completely galvanized and guarantee a long working life even under extreme conditions,  Corner cable rollers: CZPT the cable surely round each curve and cable friction is minimized. Even heavy duty cables run lightly off the rollers. The required winching power is considerably reduced and winching wires are no longer abraded as much

Nylon cable roller

260*330*230mm(H*L*W)

Aluminum cable roller

260*330*230mm(H*L*W)

Nylon wheel

140*160mm(Dia*Width)

Aluminum wheel

140*160mm(Dia*Width)

More type cable roller
Cable rollers can be divided into ground cable pulleys, power cable pulleys, overhead string pulleys, nylon pulleys, cable wire CZPT pulleys, large-diameter pulleys, dual-use cable tackles, and lifting pulleys. It is mainly used for protection when laying cable conductors. It saves time and effort. The purpose of the ground cable pulley is to change the direction of cable extension and to protect the cable from friction.

Hot sale mainly includes straight cable rollers, corner cable rollers, triple cable rollers, and some other rope cable roller and specialist cable rollers for pulling underground cables into trenches and ducts .

Application of cable roller
Cable rollers should always be used when pulling cables.
Straight cable runs are pulled in using straight cable rollers suitably placed in the cable trench to prevent the cable being
dragged on the trench bottom or in mud.
Cable roller spacing is dependent on cable type being laid and the cable pulling tension along the route. Leading cable rollers are used to support the cable over the entire drum width immediately before being pulled into the trench.Cable laying applications with bends in the route require skid plates of a radius greater than the cables minimum dynamic bending radius.

Cable roller usually packed by carton

 

Calculate the ideal mechanical advantage of pulleys

The basic equations for pulleys can be found in this article. It will also cover the different types of pulleys, the ideal mechanical advantages of pulleys, and some common uses of pulley systems. Read on to learn more! After all, a pulley is a simple mechanical device that changes the direction of a force. Learn more about pulleys and their common uses in engineering.
pulley

pulley basic equation

Pulleys work the same way as gravity, so they should withstand similar forces. Newton’s laws of motion can be used to calculate the forces in a pulley system. The second law of motion applies to forces and accelerations. Similar to this is Newton’s third law, which states that the directions of forces are equal and opposite. The fourth law dictates the direction of force. The Fifth Law states that tension is in equilibrium with gravity.
A pulley is a simple mechanism that transmits force by changing direction. They are generally considered to have negligible mass and friction, but this is only an approximation. Pulleys have different uses, from sailboats to farms and large construction cranes. In fact, they are the most versatile mechanisms in any system. Some of their most common applications and equations are listed below.
For example, consider 2 masses m. Those of mass m will be connected by pulleys. The static friction coefficient of the left stop is ms1, and the static friction coefficient of the right stop is ms2. A no-slip equation will contain multiple inequalities. If the 2 blocks are considered to be connected by a pulley, the coefficient of kinetic friction is mk. In other words, the weight of each block carries the same mass, but in the opposite direction.

Types of pulleys

A pulley is a device used to pull and push objects. Pulley systems are ropes, cables, belts or chains. The “drive pulley” is attached to the shaft and moves the driven pulley. They are available in a variety of sizes, and the larger they are, the higher the speed of power transmission. Alternatively, use small pulleys for smaller applications.
Two-wheel pulleys have 2 mechanical advantages. The greater the mechanical advantage, the less force is required to move the object. More wheels lift more weight, but smaller pulleys require less force. In a two-wheel pulley system, the rope is wound around 2 axles and a fixed surface. As you pull on the rope, the shafts above slowly come together.
Compound pulleys have 2 or more rope segments that are pulled up on the load. The mechanical advantage of compound pulleys depends on the number of rope segments and how they are arranged. This type of pulley can increase the force by changing the direction of the rope segment. There are 2 main types of pulleys. Composite pulleys are most commonly used in construction. The ideal mechanical advantage of pulleys is 2 or more.
Construction pulleys are a basic type. They are usually attached to wheel rails and can be lifted to great heights. Combinations of axes are also common. Construction pulleys can be raised to great heights to access materials or equipment. When used in construction, these pulleys are usually made of heavy materials such as wood or metal. They are secured with ropes or chains.

The ideal mechanical advantage of pulleys

The pulley system is a highly complex system with high mechanical advantages. Use a single pulley system to reduce the force required to lift an object by cutting it in half. The mechanical advantage increases as you add more pulleys, such as 6 or seven. To calculate the mechanical advantage of a pulley system, you need to count the number of rope segments between the pulleys. If the free end of the rope is facing down, don’t count it. If it’s facing up, count. Once you have your number, add it up.
The required mechanical advantage of a pulley is the number of rope segments it has to pull the load. The more rope segments, the lower the force. Therefore, the more rope segments the pulley has, the lower the force. If the rope segments are four, then the ideal mechanical advantage is four. In this case, the composite pulley quadrupled the load force.
The ideal mechanical advantage of a pulley system is the sum of the mechanical force and the force required to lift the load at its output. Typically, a single pulley system uses 2 ropes, and the mechanical force required to lift the load is multiplied by the 2 ropes. For a multi-pulley system, the number of ropes will vary, but the total energy requirement will remain the same. The friction between the rope and pulley increases the force and energy required to lift the load, so the mechanical advantage diminishes over time.
pulley

Common uses of pulley systems

A pulley system is a simple mechanical device typically used to lift heavy objects. It consists of a rotating wheel attached to a fixed shaft and a rope attached to it. When the wheel moves, the force applied by the operator is multiplied by the speed of the pulley, and the force is multiplied by the weight of the object being lifted. Common uses for pulley systems include pulling, lifting, and moving heavy objects.
The oil and petroleum industries use pulley systems in a variety of applications. Most commonly, pulleys are used in drilling operations and they are installed on top of the rig to guide the cable. The cable itself is attached to 2 pulleys suspended in the derrick, where they provide mechanical energy to the cable. Using a pulley system in this application provides the force needed to move the cable safely and smoothly.
The main advantage of the pulley system is that it minimizes the force required to lift an object. The force used to lift the object is multiplied by the desired mechanical advantage. The more rope segments, the lower the force required. On the other hand, a compound pulley system can have many segments. Therefore, a compound pulley system can increase the force a worker can exert on an object.
Safety Precautions to Take When Working on Pulley Systems

There are many safety precautions that should be observed when working on a pulley system. The first is to wear proper protective gear. This includes hard hats that protect you from falling objects. Also, gloves may be required. You should limit the amount of movement in the penalty area, and you should also keep the area free of unnecessary people and objects. Also, remember to wear a hard hat when working on the pulley system.
Another important safety precaution when working on a pulley system is to check the Safe Working Load (SWL) of the pulley before attaching anything. This will help you understand the maximum weight the pulley can hold. Also, consider the angle and height of the pulley system. Always use safety anchors and always remember to wear a hat when working on a pulley system.
Safe use of chain hoists requires training and experience. It is important to read the manufacturer’s manual and follow all safety precautions. If you’re not sure, you can actually inspect the hoist and look for signs of damage or tampering. Look for certifications for sprocket sets and other lifting accessories. Look for the Safe Working Load (SWL) marking on the chain hoist.
pulley

Example of a pulley system

Pulley systems are often used to lift items. It allows you to reduce the effort to lift and move the load by applying force in 1 direction. Pulley systems can be built and modeled to fit any type of project. This resource focuses on pulley systems and is designed to support the new GCSEs in Engineering, Design and Technology. There are also many examples of pulley systems suitable for various applications.
In the study, participants who read easy text took longer to manipulate the pulley system than those who read challenging text. In general, this suggests that participants with prior scientific experience used their cognitive abilities more effectively. Additionally, students who read simple texts spent less time planning the pulley system and more time on other tasks. However, the study did show that the time required to plan the pulley system was similar between the 2 groups.
In everyday life, pulley systems are used to lift various objects. Flagpoles are 1 of many pulley systems used to raise and lower flagpoles. They can also be used to raise and lower garage doors. Likewise, rock climbers use pulleys to help them ascend and descend. The pulley system can also be used to extend the ladder.

China Professional Design Cable Rollers Bearings Cable Sheaves and Pulleys     near me factory China Professional Design Cable Rollers Bearings Cable Sheaves and Pulleys     near me factory

China OEM Stock Bore Pulley Sheaves Wheel V Groove Cast Iron Steel Pulley SPA Spb Spc Spz with high quality

Product Description

Detailed Product Description

V-Pulley, V-Belt Pulley, Timing Pulley, Taper bush Pulley, Pilot Pulley, from 1 groove to 8 groove, customized Pulle

Pulley:
1. V-belt pulley:
European Standard: V-belt pulley for taper bushes: SPZ, SPA, SPB, SPC, up to 10 grooves
American Standard: Sheaves for taperbushes and QD bushes: 3V, 5V, 8V
Bore: Pilot bore, finish bore, taper bore, bore for QD bush

2. Models: L037, L050, L075, L100, H075, H100, H150, H200, H300, XH200, XH300, XH400
HTD: 3M-09, 3M-15, 5M-09, 5M-15, 5M-25, 8M-20, 8M-30, 8M-50, 8M-85, 14M-40, 14M-55, 14M-85, 14M-115, 14M-170, T2.5, T5, T10, T20, AT2.5, AT5, AT10, AT20 Pilot bore, taper bore, QD bore
Material: 1045 steel, aluminum and stainless steel
Surface finish: Black oxidized phosphate, anodized, zinc-plated
Standard toothed bars are also available.

Pulley Type

There are several types of pulleys. These include fixed pulleys, load multipliers and movable pulleys. Below is a description of each pulley type. A load multiplier is a special type of pulley with multiple wheels for increased lifting capacity. It is used in a wide range of applications including power transmission and construction. Some common uses of pulleys are listed below.

moving pulley

Movable pulleys work by transferring the weight of a load to another object of the same mass. Since a live pulley is inherently frictionless and weightless, the force required to lift a load with it is the same as the weight of the load. This principle applies to tall buildings and residences. It is an excellent choice for lifting heavy objects such as furniture and washing machines.
A pulley is a mechanical device with a wheel that rotates on a shaft. The axle is attached to the wheel and is usually fixed. The movable pulley can be fixed or movable, both of which can change the direction of the force on the rope. Some pulleys can also change the magnitude and direction of the force. They are ideal for a variety of applications, from lifting heavy objects to transporting objects.
Another type of movable pulley works by transmitting force to another object. It has a free axis and the total force provided by the rope tension is balanced. Since the tension on the rope is constant in each segment, pulling 1 end of the rope will double the force on the shaft, resulting in 2 mechanical advantages. This mechanical advantage is the main reason why movable pulleys are so versatile.
Another form of moving pulley is called a KWL diagram. The KWL diagram summarizes the basic concepts of the drive wheel. KWL diagrams are an excellent way to assess a student’s understanding of the concepts discussed in the course. Word questions are a great way to check whether students understand concepts. When students answer the word questions correctly, the answer is yes!
pulley

Fixed wheel pulley

If you need to move heavy objects, a single fixed wheel pulley is not a good choice. Using a single fixed pulley might be similar to using a handbag, but it’s not very convenient. This type of pulley system relies on friction to transmit motion. As a result, it can slip and isn’t always reliable. Fortunately, you can find other options that work just as well.
Fixed pulleys are the most basic type of pulley. They consist of grooved wheels and ropes attached to objects. These pulleys make lifting easier. Because the rope or cable only moves in 1 direction, the movement of the object feels lighter. And they are also easy to install. However, before you buy a fixed wheel pulley, make sure it is strong enough to support the weight of the load.
The disadvantages of fixed pulleys are obvious. One of them is the lack of mechanical advantage. A fixed pulley pulls up with the same force as a single moving pulley, and a single fixed pulley is not particularly effective as a force multiplier. However, the effect is more pronounced when you combine multiple fixed-wheel pulleys. You will get double the power! So what do fixed wheel pulleys have to offer?
Fixed wheel pulleys can be as small as a ring. A single ring pulley requires twice as much force as the weight being pulled. Adding more loops to the rope will reduce the effort required to pull the weight. The mechanical advantage of a fixed pulley is proportional to the number of strands running to the free pulley. A 100-pound pull on the free end will lift a 300-pound load.
pulley

composite pulley

Compound pulleys are pulleys that can be used to change the direction of a control wire. It can also be used to modify the mechanical force of the wire by moving the item it is connected to. In galleons, compound pulleys are more common. They are often combined with other ropes for mechanical advantage. Here are some common uses for composite pulleys.
The ideal mechanical advantage of a pulley is equal to the number of rope segments that pull up the load. This means that the more rope segments, the less force is required. A compound pulley will have the ideal mechanical advantage of 2, which means it will generate more force than a simple pulley. Composite pulleys are also more efficient at transmitting force because their number of rope segments is usually equal to the unit weight.
Composite pulley systems use more than 2 pulleys and ropes. More pulleys will reduce the force required to move heavier objects. They are usually used in large sailboats. The system is also used on construction sites. It can be used for a variety of applications, including lifting large objects or transmitting electricity. You can imagine how it would change your life if you had to move a large sailboat, but the result would be the same: a composite pulley system would make it easier to lift a large sailboat.
Composite pulleys are also known as fixed pulleys. The fixed pulley is stationary, and the movable pulley moves back and forth. The latter is more effective when used with a detachable cord or strap. On the other hand, a moving pulley is a moving pulley and it gives you a mechanical advantage. You can imagine this pulley on a flagpole.

load multiplier

The multiplication system has 3 basic parts: the rope grab, the connector, and the pulley. While some basic multipliers may combine the 3 parts, the concept remains the same. The multiplication system can make pulling the rope easier by reducing the amount of friction that occurs. Below are some examples of multiplication systems. A compact rope grab is a great option for resetting the multiplier.
The load reduction that a pulley system can achieve is proportional to the number of ropes used to support it. Although most utility pulley systems use only 4 ropes, the theoretical maximum load reduction is a quarter of the actual load. In other words, the four-wheel system only reduces the weight of a 1,000-pound load by a quarter. That would require 167 pounds of force, a far cry from the 500-pound load a single pulley system can achieve.
The mechanical advantage of a pulley system can be calculated by calculating the ratio between the forces exerted on each wire. For example, a 90-kilogram load is supported by 3 ropes, each weighing about 30-5 pounds. The ropes on pulleys A and B each carry a load of 60 kg. Using this formula, a single pulley system will yield a mechanical advantage over 2 tractors.
To calculate the force required to pull the rope over the pulley, measure the angle and deflection between the ropes. The deflection angle when added to the included angle should equal 180 degrees. A 75 degree angle requires 159% of the load force. This means a total load multiplier of four. This formula is an important tool for calculating the force multiple of the pulley.
pulley

Disadvantages of fixed pulleys

There are 2 basic types of pulleys: movable and fixed. Active pulleys are more advanced, allowing the pulley to move according to the load. They reduce the force required to lift the load. Active roller pulleys are more compact and therefore take up less space. Both types are good for lifting heavier objects, but they each have their pros and cons.
Fixed wheel pulleys can be used to lift heavy objects. This type of pulley consists of a wheel with a fixed shaft that has grooves on its edges for guiding ropes or cables. This is a simple machine as no motor or engine is required to lift objects. When 2 or more wheels are used together, the ropes around the wheels form a powerful hoist.
Single wheel pulleys are not suitable for lifting. They tend to push things down. Also, they are unreliable because they rely on friction and can slip. Also, a single wheel pulley would require a lot of space. Another disadvantage of fixed-wheel pulleys is that they make it difficult to move heavy objects easily. Single fixed-wheel pulleys also tend to slip easily, making them a poor choice for many applications.
Fixed wheel pulleys are also easier to install and maintain than manually operated ones. It requires less space and lubrication than manual pulleys. Manual pulleys can cause injury because the operator will be lifting the full weight of the heavy object. Additionally, rope slippage can lead to muscle strains and rope burns. And the system requires frequent maintenance.

China OEM Stock Bore Pulley Sheaves Wheel V Groove Cast Iron Steel Pulley SPA Spb Spc Spz     with high qualityChina OEM Stock Bore Pulley Sheaves Wheel V Groove Cast Iron Steel Pulley SPA Spb Spc Spz     with high quality