Air Jet Spinning

Air Jet spinning is a pneumatic method which consists of passing a drafted strand of fibers through one or two fluid nozzles located between the front roller of a drafting system and a take up a device.Before the sliver from the drawframe is supplied to the air-jet spinner, combing is often used, as it is imperative to get rid of any dust or trash that could obstruct the spinning jets. Twist is inserted to the fibres, mostly on the yarn surface, by the vortex created in one or two air-jet nozzeles. The resulting yarn consists of a core of parallel fibres and a sheath of wrapped (twisted) fibres. The yarn produced by air-jet spinning resembles a ring-spun yarn but is not as strong. The yarns are also inclined to shrink. High delivery rates of 150–450 m/min are possible with this technique. The feed material, i.e. the slivers, is fed to the four-roller drafting arrangement. The fibres come out of the front rollers, are sucked into the spiral orifice at the entrance of the air-jet nozzle, and are then held together more firmly as they move towards the tip of the needle protruding from the orifice. At this stage, the fibres are twisted by the force of the air-jet stream. This twisting motion tends to flow upwards. The needle, which acts as a guide on the needle holder, projects towards the inlets of a hollow spindles.

A nozzle block provides a swirling air current, which acts on the drafted fibre bundle. The needle protruding from the orifice prevents this upward propagation (twist penetration). Therefore, the upper portions of some fibres are separated from the nip point between the front rollers, but are kept ‘open’. After the fibres have passed through the orifice, the upper portions of the fibres begin to expand due to the whirling force of the air-jet stream and twine over the hollow spindle,

The fibre bundle is then sucked into the hollow spindle, and twist insertion starts when the fibre bundle is subjected to a compressed air vortex as it enters the spindle. Twist propagation towards the nip of the front rollers is prevented by the guide members acting as the centre of the fibre bundle. On leaving the guide member, the whirling action of the air current separates the fibres randomly towards the bundle.

The leading ends of all the fibres are held into the body of the yarn being formed, while the trailing ends leaving the front roller nip set are whirled up in the air and are inverted and separated from each other at the inlet of the hollow spindle. The leading ends are less subject to the air current as they are moved around the guide member towards the inlet of the spindle and converted into spun yarn. The fibres twined over the spindle are whirled around the fibre core and made into vortex yarn as they are drawn into the spindle.The finished yarn is wound onto a package after any defects have been removed. The final package is then removed automatically. The leading ends of the fibre bundle are drawn into the hollow spindle by the fibres of the preceding portion of the bundle being twisted into a spun yarn. The trailing ends of the fibres are inverted at the inlet, separated from each other, and exposed to the swirling air blown through the nozzles. The trailing ends of the fibres are thereby caused to twist around the porting of the fibre bundle being converted into a spun yarn.

In air-jet spinning, there is considerable variability in wrapper fibre configuration, with some wrapper fibres wrapping in both the S and Z directions.

Principal of Air Jet Spinning

The principle of air jet spinning involves the use of high-speed jets of compressed air to twist and bind fibers together, forming yarn. The principle of air jet spinning is based on utilizing the kinetic energy of the high-speed air jet to create a turbulent vortex that twists and binds the fibers together, ultimately forming continuous strands of yarn. This process enables efficient and rapid production of yarn with good strength and versatility.

Steps of Air Jet Spinning

Air-jet spinning, also known as air-jet spinning technology or air-jet spinning process, is a method used in the textile industry to produce yarn. It is a spinning technique that utilizes high-speed jets of air to twist and bind fibers together, forming continuous strands of yarn.

The air-jet spinning process involves several steps:

Fiber Preparation: The fibers, which can be natural fibers like cotton or synthetic fibers like polyester, are first prepared by opening and cleaning them to remove impurities and align them in a parallel orientation.
Drafting: The prepared fibers are then drafted, which involves stretching and blending them to achieve the desired thickness and consistency. This step helps in improving the uniformity and strength of the resulting yarn.
Twisting: In air-jet spinning, twisting of fibers is achieved using compressed air. A high-pressure air jet is directed onto the drafted fibers, causing them to wrap around each other and form a twisted yarn. The air-jet creates a turbulent vortex that wraps the fibers together, imparting twist and cohesion.
Winding: The twisted yarn is wound onto a bobbin or package, ready for subsequent processing or use in textile manufacturing.

Air-jet spinning offers several advantages over traditional spinning methods like ring spinning. It enables high production rates, as the process is fast and efficient. The resulting yarn has good strength and can be used for a wide range of applications in textiles and apparel. However, air-jet spun yarns may have lower yarn hairiness and some reduction in yarn quality compared to ring-spun yarns. air-jet spinning technology has been widely adopted in the textile industry for its ability to produce yarn efficiently, meeting the demands of modern textile manufacturing processes.

Advantages and disadvantages of air-jet spinning

Advantages of air-jet spinning:

High production rates: Air-jet spinning is known for its high-speed production capabilities, allowing for efficient and rapid yarn production.
Versatility: Air-jet spun yarns can be used for a wide range of textile applications, including apparel fabrics, home textiles, and industrial textiles.
Good yarn strength: Despite some limitations, air-jet spun yarns generally exhibit good strength, making them suitable for various textile applications.
Reduced hairiness: Air-jet spinning can result in lower yarn hairiness compared to certain other spinning methods, which can contribute to improved fabric quality and aesthetics.
Fiber compatibility: Air-jet spinning can work well with different types of fibers, including natural and synthetic fibers, allowing for flexibility in fiber selection.

Disadvantages of air-jet spinning:

Reduced yarn quality: Air-jet spun yarns may have lower yarn quality compared to certain other spinning methods like ring spinning. They can exhibit higher hairiness and reduced yarn strength.
Limited yarn count range: Air-jet spinning is more suitable for producing medium to coarse yarn counts. It may face limitations in producing very fine or very thick yarns, restricting its application in certain textile sectors.
Energy consumption: Air-jet spinning requires the use of compressed air, which can result in higher energy consumption compared to other spinning techniques, impacting production costs and environmental sustainability.
Complex equipment and maintenance: Air-jet spinning machines are complex and require regular maintenance to ensure optimal performance. The intricate air-jet nozzles and components can be susceptible to wear and tear, leading to increased maintenance costs.
Fiber limitations: Air-jet spinning may have limitations in handling certain fibers, particularly short staple fibers, which can impact yarn quality and production efficiency.

While air-jet spinning offers advantages such as high production rates and versatility, it is important to consider the potential drawbacks and evaluate its suitability for specific yarn and fabric requirements.

The main advantages of air-jet spinning can be found in two main directions: efficiency and flexibility
Air jet spun yarn have a small ,but important share of cotton/polyester market.
Air -jet spinning allows the production of finer yarns as compared to rotor yarn.
The strength decreases as the yarn becomes courser.
The biggest disadvantage is in difficulty in the spinning of 100% cotton yarn.
There are quite high requirements for the quality of the slivers, which call for a higher number of drawings or even combing of the slivers.
The extra twists of the yarns, necessary to increase the yarn tenacity, are reflected in the harsh hand of the fabrics which therefore need particular optimization in finishing.

Yarn Characteristics

It is slightly different from the ring spun yarn, it is somewhat:

Weaker
Stiffer
Harder
Good evenness
low tendency to pilling

Airjet Spinning Specifications

Spinning positions per machines: 60
Delivery speed: 120-450 m/min
Raw material: synthetic fibres and blends(combed cotton)
Count range: 10-40 tex; Ne 15-60
Feed stock type: draw frame sliver
Type of yarn: bundled single yarn
Yarn characteristics: rather low strength, low hairiness, rough outer surface
Field of use: ladies outer clothing, shirt material
Advantage: low production cost, low personnel demand
Remark: three draw frame necessary

Frequently Asked Questions | FAQs

What is air-jet spinning ?

Air-jet spinning is a textile manufacturing technique that uses high-speed jets of air to twist and bind fibers together, creating yarn. It is a fast and efficient method for producing strong and versatile yarns.

What is the basic principle of air-jet spinning ?

The basic principle of air-jet spinning is to use high-speed jets of compressed air to twist and bind fibers together, forming yarn. The air-jet creates a turbulent vortex that wraps the fibers around each other, imparting twist and cohesion. This process allows for the efficient and rapid production of yarn with good strength and versatility.

What are the disadvantages of air-jet spinning?

While air-jet spinning offers various advantages, it also has some disadvantages. Here are a few:
Reduced yarn quality: Compared to other spinning methods like ring spinning, air-jet spun yarns may have lower yarn quality. They tend to have higher hairiness, which can affect the appearance and texture of the fabric produced from these yarns.
Limited fiber compatibility: Air-jet spinning works best with certain types of fibers, particularly medium-to-long staple fibers. Short staple fibers, such as cotton, may pose challenges in achieving optimal yarn quality and production rates.
Increased energy consumption: The process of air-jet spinning requires the use of compressed air, which can result in higher energy consumption compared to other spinning techniques. This can impact production costs and environmental sustainability.
Limited yarn count range: Air-jet spinning is more suitable for producing medium to coarse yarn counts. It may face limitations in producing very fine or very thick yarns, restricting its application in certain textile sectors.
Equipment complexity and maintenance: Air-jet spinning machines are complex and require regular maintenance to ensure optimal performance. The intricate air-jet nozzles and components can be susceptible to wear and tear, leading to increased maintenance costs.

Despite these disadvantages, air-jet spinning remains a valuable spinning technology due to its high production rates and suitability for a wide range of textile applications. Ongoing advancements in the field continue to address some of these limitations and improve the overall performance of air-jet spinning systems.

How fast is air-jet spinning?

Air-jet spinning is known for its high production rates, making it one of the fastest spinning methods in the textile industry. The exact speed of air-jet spinning can vary depending on various factors such as the machine type, yarn count, fiber characteristics, and process settings. However, in general, air-jet spinning machines can achieve spinning speeds ranging from 2,000 to 3,500 meters per minute (m/min) or even higher in some cases.
These high speeds enable efficient yarn production, contributing to increased productivity in textile manufacturing. The fast spinning rates of air-jet spinning machines allow for rapid yarn formation, making it suitable for high-volume production and meeting the demands of modern textile industry requirements.

What is difference between rotor and air jet spinning ?

Rotor spinning and air-jet spinning are two different methods used in the textile industry to produce yarn. Here are the key differences between the two:
Principle of Operation:
Rotor Spinning: Rotor spinning involves the use of a rotating rotor or spinning disc, which draws the fibers from a sliver and twists them into yarn using centrifugal force.
Air-Jet Spinning: Air-jet spinning uses high-speed jets of compressed air to twist and bind fibers together, forming yarn. The air-jet creates a turbulent vortex that wraps the fibers around each other, imparting twist and cohesion.
Fiber Handling:
Rotor Spinning: In rotor spinning, the fibers are typically fed into the spinning system as a sliver or roving, which is a loose and untwisted strand of fibers.
Air-Jet Spinning: Air-jet spinning requires well-opened and parallelized fibers, which are prepared beforehand. The prepared fibers are drafted and then subjected to the air-jet spinning process.
Production Speed:
Rotor Spinning: Rotor spinning machines can achieve relatively high production speeds, but they are generally slower compared to air-jet spinning.
Air-Jet Spinning: Air-jet spinning is known for its high production rates and is considered one of the fastest spinning methods in the textile industry.
Yarn Quality:
Rotor Spinning: Rotor-spun yarns tend to have higher hairiness and lower yarn strength compared to some other spinning methods. However, they can provide good yarn evenness and are often used for coarser yarn counts.
Air-Jet Spinning: Air-jet spun yarns may have higher hairiness and some reduction in yarn quality compared to certain other spinning methods like ring spinning. However, they offer good strength and are versatile for various textile applications.
Yarn Applications:
Rotor Spinning: Rotor-spun yarns are commonly used for applications that do not require high-quality or fine yarns, such as denim, towels, and other coarse fabrics.
Air-Jet Spinning: Air-jet spun yarns are used for a wide range of applications, including apparel fabrics, home textiles, and industrial textiles.

Both rotor spinning and air-jet spinning have their advantages and applications, and their suitability depends on factors such as yarn requirements, production speed, and fiber characteristics. Textile manufacturers choose the spinning method based on specific needs and desired yarn properties.

What is difference between air jet and air vortex spinning ?

Air jet spinning and air vortex spinning are two distinct methods used in the textile industry to produce yarn. Here are the key differences between the two:
Principle of Operation:
Air Jet Spinning: Air jet spinning utilizes high-speed jets of compressed air to twist and bind fibers together, forming yarn. The air-jet creates a turbulent vortex that wraps the fibers around each other, imparting twist and cohesion.
Air Vortex Spinning: Air vortex spinning also employs compressed air, but the principle of operation differs. In air vortex spinning, the fibers are transported and twisted by an air vortex created by a rotating device called an air vortex spinner. The fibers are lifted and wrapped around the core yarn, forming the final yarn structure.
Fiber Handling:
Air Jet Spinning: Air jet spinning requires well-opened and parallelized fibers, which are prepared beforehand. The fibers are drafted and then subjected to the air-jet spinning process.
Air Vortex Spinning: Air vortex spinning can handle a wider range of fibers, including coarser and shorter staple fibers. The fibers are fed into the spinning system without extensive preparation or parallelization.
Twisting Mechanism:
Air Jet Spinning: In air jet spinning, the twist is imparted to the fibers by the turbulent air vortex created by the high-speed air jets. The fibers are twisted and bound together as they wrap around each other.
Air Vortex Spinning: Air vortex spinning relies on the rotation of the air vortex spinner to create a swirling vortex of air. The fibers are lifted and twisted around the core yarn by the air vortex, resulting in the formation of the yarn structure.
Yarn Properties:
Air Jet Spinning: Air jet spun yarns tend to have lower yarn quality compared to some other spinning methods like ring spinning. They may have higher hairiness and reduced yarn strength.
Air Vortex Spinning: Air vortex spun yarns generally exhibit better yarn quality, with lower hairiness and improved yarn strength compared to air jet spun yarns.
Both air jet spinning and air vortex spinning offer advantages and have specific applications in the textile industry. The choice between the two methods depends on factors such as yarn requirements, fiber characteristics, and desired yarn properties.