Types of Fabric Dyeing Machines: Working Principal & Properties
Recently, during a class, my professor brought up a very interesting topic. He discussed the ‘Global Competence’ of the Textile Engineers that our country is producing. Many important points were made by him. Among them, the most important was the ‘Basic Understanding of the Subject’ & ‘Our Naïve Approach’ towards it.
So, here I am trying to gather all the necessary things that are thought to be ‘Basics’ in a series of posts. There are different types of dyeing machines. Among them, fabric dyeing machines are of the highest importance.
Therefore, I will start with the types of fabric dyeing machines.
Types of Fabric Dyeing Machines Based on Dyeing Process

Types of Fabric Dyeing Machine Based on Dyeing Process
Before we get into the technical side of it, let’s apply our common concepts first. We watch various TV commercials every day which claim that their products are produced without the use of the hand. What they mean is from start to finish no manual material handling is needed i.e. they feed the Raw Materials as input & receive the final product as output without any intervention. This is called Continuous Process & Batch/Dis-continuous project is exactly its opposite. In the semi-continuous process, both concepts are implemented.
The above-mentioned concept can also be applied to Dyeing processes as well. If we consider fibers as in input & garments as output than we would have to agree that the overall process is the Batch process.
Batch/Dis-Continuous Fabric Dyeing Machine
- Here a certain/known amount of material/fabric is brought under repeated contact with dye liquor & then transported to carry out the subsequent processes.
- This type of machines allow processing in rope form (e.g. winches, jets, etc.) or in open width form (e.g. jigger)
- For knit dyeing this process is used almost everywhere in our country
Semi-Continuous Fabric Dyeing Machine
- Here dye solution is applied by padding & then it’s batched/stored in certain conditions for fixation.
Different Padding Baths
- Padding can have the advantage of high dye yield. Padded goods are usually “batched”– wrapped in plastic and left for some period of time for the dye to attach to the fibre, or steamed to fix the dye quickly.
- Padding methods are sometimes used for other textile processes such as bleaching. & then it’s batched/stored in certain conditions for fixation.
- The subsequent processes (washing, drying, etc) are done afterwards.
Continuous Fabric Dyeing Process
- This type of process is aimed at higher production.
- Here dry undyed fabric enters at one end & dry coloured fabric is leaves at the other end. This is why it’s also called dry-to-dry
- All the units for example padding, steaming, washing, drying etc. are just set one after another
A typical diagram is shown below:

Continuous Dyeing/Dry-to-Dry Process
Name of the Fabric Dyeing Machines |
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Batch Dyeing Machines |
Semi-continuous Dyeing Machines |
Continuous Dyeing Machines |
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Principles of Batch/Discontinuous Fabric Dyeing Machine
In the following chart the principles, form in which they are fed into the different Batch machines are given –

Batch/ Dis-continuous Dyeing Process
Why Rope form is used/what are the advantages of rope form processing?
- It’s the easiest method of processing.
- Handling & Storage is easy.
- Ease of transportation as it can be transported to virtually any distance and any direction by passing it through circular guides.
- The fabric doesn’t undergo much tension widthwise which is a very significant factor as winch machine is extensively used for knits which has low dimensional stability.
Now, I will try to discuss about different machines very shortly.
Winch/ Beck Dyeing Machine
Moving Material & Stationary Liquor
Why it’s called winch ?
A horizontal rotor/reel is used to circulate the fabric endlessly. This rotor/reel is known as winch. The winch maybe elliptical or circular in cross-section. The elliptical winches exerts minimum tension but high mechanical action by giving long & short folds when the fabric rotates.

Winch Dyeing Machine

Schematic Diagram of Winch Machine
Advantages of Winch Dyeing Machine
Disadvantages of Winch Dyeing Machine
Jigger Dyeing Machine
Moving Material & Stationary Liquor
Jigger Dyeing Machine Atmospheric Jig Dyeing Machine At speed in excess of around 110 m/min, on small diameter rolls, the dye liquor may be thrown out of the rotating roll by centrifugal force.
Why the let-off & take-up speed should be kept constant?
We know that Surface Speed of a roller = ΠDN ; where Π = Constant
D = Diameter of the roller
N = RPM of the roller
So, what happens when the take-up roller has taken up 500 meters of fabric?
The diameter of the roller has now been increased so the surface speed has also been increased. As a result the roller will take-up more length of fabric/minute which will result in low pick-up.
So, the pick-up will decrease gradually as the diameter of the take-up roller is increasing if the RPM is kept constant. This will result in shade variation. The RPM must be varied accordingly.
The Factors for Controlling Dyeing Are –
Advantages of Jigger Dyeing Machine
Disadvantages of Jigger Dyeing Machine
Jet Dyeing Machine
Moving Material & Moving Liquor
Jet Dyeing Machine

Horizontal Jet Dyeing Machine

Angular View of Overflow Jet Dyeing Machine
How the turbulence of the liquor is created to transport the fabric along with it?
It’s based on Venturi tube.

Venturi Tube
From Bernoulli’s equation we can arrive at the following conclusion –

Bernoulli’s Equation to Determine the Change in Pressure & Velocity
So, we can simply say –

Representation of Differential Pressure & Speed at Different Area of a Venturi Tube
That narrow open end causes tremendous increase in speed of flow, forcing the fabric to move along with circulation of liquor. This also helps in dye penetration along with preventing the fabric from touching the walls of the tube.
You can see this video for further clarification.
What happens when the orifice of the Jet is too small or large & why accurate positioning of the Jet is important?
The size of the actual orifice depends on the fabric weight and width.
For a given rope of fabric, too small a jet produces more creases because the fabric rope is more compressed in the jet and may even jam.
Too large a jet gives inferior rope transport.
Accurate positioning of the jet avoids giving a circular motion to the liquor that might cause twisting of the rope and more creasing. Rectangular jets help to open up the fabric rope.

Unique Nozzle Design
In the above nozzle system you can control the rate of flow of the dye liquor according to the kind of cloth by adjusting the gap so the nozzle doesn’t need to be changed.
There are 3 types of Jet Dyeing machines, which are – By now, I hope you have a clear idea about the types of fabric dyeing machines. And I don’t have any intentions to make this article any longer. To learn about the continuous and semi-continuous dyeing process you can read our other post.
Advantages of Jet Dyeing Machine
Disadvantages of Jet Dyeing Machine
REFERENCES
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