POMNylon PAPTFEPEEK SleeveSpacer Plastic Bushing

2 month ago

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5 year

Product details

A sleeve is a component used on the exterior of mechanical parts to achieve functions such as sealing and wear protection. It refers to a ring-shaped sleeve that serves as a cushioning layer. In the field of valve applications, sleeves are typically located inside the valve cover and are made of corrosion-resistant materials such as polytetrafluoroethylene (PTFE) or graphite, primarily for sealing purposes.

The Function of Bushings

Bushings offer high flexibility in application and serve multiple purposes. In summary, bushings are components designed to protect equipment. Their use reduces wear, vibration, and noise in equipment while providing corrosion resistance. Additionally, bushings facilitate maintenance of mechanical equipment, simplify equipment structure, and streamline manufacturing processes.

The role of bushings in actual applications is closely related to their application environment and purpose. In valve applications, bushings are installed inside the valve cover to encase the valve stem, thereby reducing valve leakage and achieving a sealing effect. In bearing applications, the use of bushings reduces wear between bearings and bearing housings and prevents the expansion of gaps between shafts and holes.

Bearing Sleeve Materials

Bearing sleeves are typically made of soft metals, rubber, nylon, and non-metallic polymers. These materials are relatively soft in texture and have lower production costs. In various harsh working environments, bearing sleeves withstand vibration, friction, and corrosion to protect the components they enclose. Additionally, bearing sleeves are easy to replace when damaged, have low replacement costs, and offer good economic efficiency.

Bearing Selection Factors

Bearings have a wide range of applications and come in various types. To select the appropriate bearing, it is essential to consider its intended use, as different operating conditions require different bearing models. The primary factors considered in bearing selection include the pressure, speed, pressure-speed product, and load characteristics that the bearing must withstand. Additionally, whether the sleeve is lubricated and the lubrication condition also determine its performance and service life.

Actual Applications

Applications include: packaging machinery, textile machinery, mining machinery, metallurgical machinery, printing machinery, tobacco machinery, forging machinery, various machine tools, and interchangeable mechanical transmission connections. For example: pulleys, sprockets, gears, propellers, large fans, and various other connections; Features: high torque, high precision, easy and quick installation and removal, simple operation, good positioning, reduced scrap rate of mating shafts and hubs, reusable, does not damage mating surfaces, making it the most ideal and economical choice currently available.

1. Installation: The sleeve is pre-lubricated at the factory and can be installed and used directly. During installation, first insert three bolts into the threaded holes of the flange on the other component and distribute them evenly around the circumference to separate the inner and outer sleeves. Then place the expansion sleeve in the hub hole at the designed position and use a torque wrench to tighten the bolts. The tightening method is to tighten each bolt to only 1/4 of the rated torque each time. The tightening sequence should be alternating left and right symmetrically from the gap, ensuring that the rated torque value is reached.

2. Disassembly: When disassembling, first loosen all bolts by a few turns. Then, alternately insert bolts into the disassembly holes to loosen the expansion sleeve.

3. Protection: Prevent contamination of the expansion sleeve during installation. In outdoor operations or machines with poor working environments, regularly apply anti-rust grease to the exposed ends of the expansion sleeve and bolts. Select expansion sleeve types with better anti-rust properties. The expansion coupling sleeve is a modern, advanced mechanical component. It is widely used internationally to achieve component and shaft connections, relying on the pressure and friction generated between the mating surfaces by tightening 12.9-grade high-strength screws to transmit loads, making it a new type of keyless connection device.

Can new plastic bushings replace metal bushings?

For many years, metal bushings have been the only choice for industrial applications. Newer plastic manufacturing technologies allow for the production of composite plastics that can serve as suitable alternatives to metal structural materials for bushings.

Some key characteristics of composite plastic bushings are:

Low wear rate

Lightweight

Low coefficient of friction (maintained under heavy loads)

Ability to conform under load

High performance grade (comparable to other sleeve bearing materials)

OD compatibility with standard sintered bronze dimensions (for easy upgrading)

Why do plastic bushings outperform metal bushings?

Composite plastic bushings are composed of thermoplastic alloys and solid lubricants, with a fiber matrix added for reinforcement. They are made from various low-cost plastics (such as nylon, UHMW, polyethylene, and PTFE) and more expensive high-performance plastics (such as Vespel, PEEK, and Torlon), suitable for applications involving higher temperatures or greater loads. Generally, many composite plastics used to manufacture bushings are cheaper than their metal counterparts. In some cases, they can be up to 25% cheaper.

Despite their lower cost and lighter material weight, composite plastic bushings typically outperform metal bushings in terms of performance, such as:

Longer operating life under harsh environmental and operational conditions

Lubrication-free operation (as required by metal bushings)

Demonstrate excellent corrosion resistance (no lubrication required)

Produce less friction (no lubrication required)

Demonstrate higher durability and service life (minimizing maintenance and replacement needs)

Advantages of plastic bushings

As mentioned above, composite plastic bushings typically outperform metal bushings. Other advantages of using composite plastic bushings instead of metal bushings include:

Customizable composite materials to meet different engineering standards. Plastic bushings are chemically resistant, can withstand high temperatures up to +482°F, and are lubrication-free and maintenance-free. They are cost-effective, have a long service life, can handle high loads, are suitable for use in humid environments, are FDA-approved, and offer many other useful features.

Virtually maintenance-free. Plastic bushings are self-lubricating, eliminating the need for manual application and reapplication of lubrication. The absence of lubrication also provides better resistance to debris and other contaminants, reducing the risk of plastic bushings becoming stuck.

Reduced equipment costs. Plastic bushings have a lower coefficient of friction and higher wear resistance, making them highly durable. Since they often have a longer service life and lower cost, switching from metal to plastic can save industry professionals up to 25% in costs.

No lubrication required. Since plastic bushings are self-lubricating, they do not attract dirt and dust like messy grease or oil.

More consistent coefficient of friction (COF). Plastic bushings are designed to maintain a low COF, reducing heat and wear. Additionally, plastic does not scratch like metal, helping to maintain a stable COF throughout the bushing's lifespan.

Greater corrosion resistance. Unlike metal bushings, water, salt, and other chemicals do not affect the performance of plastic bushings. Similarly, unlike metal bushings, water can even be used as a lubricant in plastic bushings.