The Essential Knowledge about Winding
Tensioning Device
During winding yarn is passed through tensioning device to control the yarn tension.
Effects of tension on yarn and Yarn Package:
Too high tension:
Can damage the yarn.
Increase breakage rate of yarn.
Change elongation properties of yarn.
Can change molecular structure of yarn (in case of man-made fibre) which affects the dye ability; and causes random variations in color shading.
Can lead to hard yarn package.
Too low tension:
Can lead to unstable packages which will not unwind cleanly.
Loosely wound package have tendency to “slough off”.
Variation of Tensioning Device
A. According to working principle
• Capstan tensioner
• Additive tensioner
• Combined tensioner
• Automatic tensioner
B. According to the type of working member acting on the yarn
Washer type tensioner
Disc type tensioner
Comb type tensioner
Roller type tensioner
Ball type tensioner
Two–zone tensioner
Factors Influences for selection of Tensioner
• The device must be reliable to control uniformly in tension.
• It must be easily thread able.
• It must not introduce differences in twist.
• It must not be affected by wear.
• It must be easily adjustable.
• It must not be affected by the presence of oil and dirt.
• It must be capable of easy cleaning.
• The operating surface must be smooth.
• It must be inexpensive or cheap.
• It must be simple in design & operation.
• It must not cause damage for yarn.
Yarn Guide
In winding or unwinding, it is necessary to control the yarn path. For controlling the yarn path, yarn guide is used. There are mainly two types of yarn guide:
- A yarn end is required for threading.
• Takes extra time in threading
• Low production
• More friction
- A yarn end is not required for threading.
• Easy threading
• High production
Function of Yarn Guide
To control the yarn path.
Minimize yarn vibration.
Reduce chance of balloon formation.
Yarn Cleaner
Yarn cleaner is the device which is used to remove the following faults of yarn in order to increase the yarn quality and weaving efficiency.
The following faults removed by yarn cleaner-
• Thick and thin places in the yarn.
• Slubs and neps.
• Loose fibre.
• Foreign matters
Types of Yarn cleaner
• Metal sheet type/metal slit type ,
• Comb type,
• Ordinary metal slit type,
• Serrated blade type,
• Disc type,
• V- type.
Auxiliary Functions of Winding
• Creeling: Creeling is the placement of full packages in position ready to be unwound as a part of transfer operation.
• Piecing: Piecing is finding and connecting of the ends on the packages. The connection between the ends can be made by knotting, adhesion or welding; but the former is by far the most common.
• Doffing: Doffing is the removal of the newly wound packages and the replacement of these by empty packages which will receive yarn during the transfer process.
Winding Efficiency Depends on the following factors-
Spindle or drum speed: The higher the speed the more is the winding efficiency
Yarn Count: Yarn count is proportional to winding efficiency
Yarn quality: If yarn quality increases then winding efficiency increases
Worker efficiency: The more efficient the work is the more efficient the winding will be.
Humidity: Humidity is reciprocal or inversely proportional to winding efficiency.
Work load per worker: If the work load on each worker is less then efficiency of winding will be more.
Maintenance and over hauling: If the maintenance and over hauling of the machine is not correct then efficiency of winding will decrease.
Power failure: If power failure rate increases the winding efficiency will decrease.
Creeling time: The more the creeling time the less is the efficiency.
Doffing time: The more the doffing time the less is the efficiency.
Capacity utilization: When capacity utilization decreases then efficiency increases.
Reasons for Lower Efficiency
Power failure
Improper maintenance and over hauling
Natural disasters
Less skilled labor
Labor unrest
Shortage of machine parts and raw materials
Strike
Maintenance problems