Unit -1

Ring Frame

1.1Introduction and objectives of a Ring Frame, nomenclature of various parts of a Ring

Frame,passage of material through it

https://youtu.be/hxrCLUbA_RQ

Link regarding principle of Ring spinning

Introduction of Ring Frame Machine:

Ring spinning is a method of spinning fibres such as cotton. Spinning process is done by Ring frame

machine. Ring frame converts the roving bobbin into the yarn. The roving bobbin taken from roving

process is mounted on the Ring frame either automatically or manually. The ring frame stretches and

drafts the material.

Fig: Ring frame machine

Objectives of Ring Frame:

To reduce the mass of the material by drafting until the required fineness is obtained.

To twist the drafted yarn by twisting to obtain maximum strength.

To wind the twisted yarn onto the bobbin by winding process for suitable storage, transportation and

further processing.

Main Parts of Ring Frame:

Roving Bobbin: Inserted in holders.

Roving Guide: To feed roving correctly.

Creel: To hold the roving bobbin over the roller beam.

Guide Rail: Guide the roving into the drafting.

Drafting Arrangement: For drafting of material.

Yarn Guide: To guide the yarn to give path to the yarn.

Spindle: Hold the yarn loosely or tightly.

Traveller: Help in the insertion of twist in yarn.

Ring

Guide the circular run of the traveller.

Separator: Separate the yarn to avoid entanglement of yarn during balloon formation.

Operations of different zone of ring frame are described below:

Creel Zone:

When the roving is brought for the process of ring spinning, it needs to be un-winded properly. For this

purpose, the roving is held in a vertical position with the help of roving hangers on creel

rods.https://youtu.be/rv4C2vuA15k

Link of Introduction,Objective and parts of Ring frame

1.2 Drafting, function of the drafting system, study of top arm drafting system, apron

drafting, advantages of apron drafting.

Drafting and Drafting Zone:

To reduce the weight per unit length by drafting in which roving is passed through three to four rollers

to attain differential speed. Drafting is the most important part in the ring spinning process. The drafting

directly influences the strength and evenness of the yarn. The ring spinning frame uses a 3 by 3 drafting

with three top and three bottom rollers and the middle rollers covered with aprons. The aprons are

made of rubber material and are used to guide the yarn. The top rollers are coated with rubber and are

negatively driven, hence they have no drive. The bottom rollers are coated with steel and are positively

driven. The top rollers are driven by the bottom rollers with the help of pressure arm. The pressure arm

applies pressure on the top rollers which influences the bottom rollers to start moving. When the

bottom rollers start moving, the top rollers are also given drive and thus they move. So pressure arm is

also an important component in the drafting area. A total draft of 15-40 and in some cases even up to

50 can be given in the ring spinning frame.

Fig: Drafting of ring frame (Image courtesy: https://www.rieter.com)

Apron:

Rubber Apron is made of synthetic rubber material, with excellent wear-resistance/oil-

resistance/ageing-resistance and smooth surface. In addition, it is of good stability, flexibility & wide

application. It is used in drafting system of ring frame and some other modern drafting system in

spinning machine. It contains cradle for guiding its direction of length.

Figure: Rubber apron

Rubber cot:

It is one type of synthetic rubber material which is used in top rollers of ring frame drafting system. The

rubber cots also used on drawing frames, combing machines & spinning frames. Its hardness can be

varied. The hardness of rubber cots is expressed by degree. Generally harder cots are used in the back

rollers and softer rollers are used in front rollers.

Hardness ranges are given below-

Soft: 60° to 70° Shore

Medium: 70° to 90° shore

Hard: above 90° shore

80° to 85° shore are mostly used at the back roller and 63° to 65° shore at front roller.

Figure: Rubber cots

Drafting system can be broadly classified under two heads namely –

1. Regular drafting system without apron. And

2. Drafting system with apron.

The system with apron can again be classified into three groups –

1. Single apron system.

2. Double apron system. and

3. Multiple apron system.

Example of regular drafting system without apron –

a. Conventional three roller system.

b. Improved system.

c. H and B four rollers long draft system.

d. 5 over 4 roller systems.

Example of single apron drafting system –

a. Saco – Lowell. Both systems.

b. Saco – Lowell. Shaw system.

c. Saco – Lowell. Z system.

d. Toenniessen system. and

e. Versatex LS system.

Example of double apron drafting system –

a. Casablancas double apron system.

b. Casablancas “L” system with flexible bar.

c. Saco – Lowell thread rollers duo-Roth system.

d. SKF pendulum top arm weighting system. And

e. Saco – Lowell 4 – roller Duo – Roth system.

Example of multiple Apron drafting system –

a. Casablancas “N” system.

b. Nittoh’s Semi-super high draft system.

c. OM – S super high

1.3Introduction to rings, sizes and different types of rings, ring travellers, its functions, types

of ring travellers, their sizes. Numbering of ring travellers

https://youtu.be/54bYKvwsYwg

Link regarding ring and ring travellers

Ring:

The ring are made of low carbon steel i.e. soft steel or ceramic in the form of a bar which modelled into

ring shaped either by bending and welding or by pressing by means of dies and then the stock is given

the desired projection term as ring flange.

Function:

There are some important functions of ring. These are given below:-

Ring guides the circular run of the traveller.

It also helps in twisting by means of running of the traveller.

It also acts as a track of traveller.

Figure: Ring cups

Classification of ring:

A) According to origin or element:- i. Metallic ring

ii. Ceramic ring

B) According to number of flange:-

i. Single flange ring, ii. Double flange ring

Relation between bobbin dia and Ring dia:

B= 0.39R

Where B= Bear bobbin dia and R= Ring dia.

Flange:

The path of traveller on the ring is called flange. It may be single or double.

Flange width:

The term flange width express the difference the outer diameter and inner diameter of a ring. Flange

width is expressed in flange no.

Flange width= (Flange no. + 3)/32 inch

Flange no. Flange width (mm)

1 3.2

1.5 3.6

2 4

Traveller:

Traveller is the most tinny and simple mechanical element in ring frame which carries the most

important function like simultaneous twisting, winding, thread guide etc.

Function of traveller:

Traveller does some important in ring frame. These are mentioned below:-

Twisting on the drafted strand of fibre.

Winding of the yarn on the bobbin.

Maintain winding tension of the yarn by the frictional resistance between the ring and the traveller.

It acts as a guide for yarn on the way to be wound on the bobbin.

Figure: Travelers

Traveller speed and its effects:

Traveller does not have a drive of its own. It drags along behind the spindle. Since the spindle rotates at

a high speed, a high contact pressure is generated between the ring and traveller during winding, mainly

due to centrifugal force. The pressure introduces strong frictional forces which in turn lead to significant

generation of heat. It is the important problem of ring/traveller.

The front roller delivers a certain length of yarn. That’s why length wound up must corresponds to the

difference in peripheral speed of traveller and spindle. The speed difference is due to lagging of the

traveller relative to the spindle.

Parts of traveller:

There are three parts of a traveller. They are given below:-

Bow

Horn

Flange

Types of traveller:

Travelers can be classified into following two ways:-

A) According to shape:-

C – traveller

Elliptical traveller

B) According to the X-section of wire:

Round traveller

Flat traveller

Semi-circular traveller

Specification of traveller:

A ring traveller is specified by the followings-

Traveller no.: 1, 2, 3, 1/0, 2/0, 3/0 etc.

Cross section of the wire and shape

Flange no.

Surface finish- Stainless steel made, Carbon finish,Nicle finish etc.

Type of materials etc.

Notation of traveller:

A traveller can be notified as follows-

3/0 MS/hF

5/0 MS/FF

7/0 HI-NI/ hf

Here,

3/0- Traveller number

MS- Mild steel

Hf- Half flange

FF- Full flange

HI-NI- High Nickle Finish

Traveller Number or size of traveller:

Here, if the weight of 10 traveller is 10 grains then the number of those traveller is 1 and so on.

Recommended traveller no. for various yarn counts:

Count (Ne) Traveller No.

16 2

20 1-2/0

30 3/0-4/0

40 6/0-8/0

50 10/0-12/0

60 13/0-15/0

80 16/0-19/0

100 19/0-20/0

Unit -2

Twisting

2.1Insertion on of twist into the yarn, S/Z twists, effect of twist on yarn, selection of TM for

various counts, ring and travellers speeds

https://youtu.be/aABkSc3KY1Q

Link for twisting mechanism

Twisting: When the roving is drafted, the yarn undergoes twist insertion. The twist is given to strengthen the yarn.

The yarn after being drafted comes from the front rollers and passes the yarn guide. The yarn guide is

adjusted to be centered above the spindle. They lead the yarn centrally over the axis of spindle. Now the

yarn passes down to the spindle assembly where it is threaded through the traveller.

Fig: Yarn twist insertion in ring frame

The traveller imparts twist to the yarn and is responsible for winding the yarn onto the cop. However a

second device, the spindle is required for winding. The traveller is fixed with the ring and does not have

its own drive but is only carried along the spindle. The rings are responsible for the rotation of yarn. The

yarn comes in between the traveller and the traveller rotates on the ring along with the yarn. As the

yarn rotates, number of twists are inserted.

Fig: Ring and traveller (Image courtesy: https://www.ptj.com.pk)

Twist is the number of turns about its axis per unit of length of a yarn or other textile strand. Twist is

expressed as turns per inch (tpi), turns per meter (tpm), or turns per centimeter (tpcm). It is a very

essential process in the production of staple yarn, twine, cord and ropes. Twist is inserted to the staple

yarn to hold the constituent fibres together, thus giving enough strength to the yarn, and also producing

a continuous length of yarn. The mechanism of twist insertion to the strand during ring spinning has

been studied. The twisting of the strand occurs not only due to the rotation of twisting elements, but

also due to the winding of yarn on the package. When the yarn is wound on a stationary cop by gripping

and winding the yarn by hand, for every coil of yarn wind one turn of twist to the yarn is inserted. Now

we will discuss about way of twist insertion to the yarn.

Yarn twist defined as the spiral deposition of the components of a twist is the measure of the spiral

turns given to a yarn in order to hold the constituent fibres or threads together – Skinkle.

When a strand is twisted the component fibres tend to take on a spiral formation, the geometric

perfection of which depends on their original formation – Morton.

Twist may be defined as the rotation about the yarn axis of any line drawn on the yarn which was

originally, before twisting parallel to the yarn axis .

Twist may also be defined as thread which is usually the result of relative rotation of the two ends.

Twist direction:

The direction of the twist at each stage of manufacture is indicated by the use of letters S or Z in

accordance with the following convention:

A single yarn has S twist if, when it is held in the vertical position, the fibres inclined to the axis of the

yarn conform in the direction of the slope to the central portion of the letter S. Similarly the yarn has Z

twist if the fibres inclined to the axis of yarn conform in the direction of slope to the central portion of

the letter Z.

The Amount of Twist: the amount of twist in a thread at each stage of manufacture is denoted by a

figure giving the number of turns of twist per unit length at that stage. It affects the characteristics and

properties of a yarn including appearance, behaviour and

durability.

The amount of twist is an important factor in finished consumer goods. It determines the appearance as

well as the durability and serviceability of a fabric. Fine yarns require more twist than coarser yarns.

Warp yarns, which are used for the length wise threads in a woven fabric, are given more twist than

filling yarn which is used for cross wise threads.

The amount of twist also depends upon the type of the fabric to be woven:

Yarns intended for soft surfaced fabric are given slack twist. They are called as soft twisted yarns.

Yarns intended for smooth surfaced fabrics are given optimum twists. Such twisted yarns contribute

strength, smoothness and elasticity.

Yarns intended for crepe fabrics are given maximum amount of twists.

Types of Twist

S-twist

Z-twist

Effect of twist on yarn The twist in the yarn has a two-fold effect; firstly the twist increases cohesion

between the fibres by increasing the lateral pressure in the yarn, thus giving enough strength to the

yarn. Secondly, twist increases the helical angle of fibres and prevents the ability to aioli the maximum

fibre strength to the yarn. Due to the above effects, as the twist increases, the yarn strength increases

up to a certain level, beyond which the increase in twist actually decreases the strength of staple yarn.

The continuous filament yarn also requires a small amount of twist in order to avoid the fraying of

filaments and to increase abrasion resistance.

Twist insertion onto the yarn when the spindle leads the traveller. In ring spinning, both the spindle and

traveller rotate in the same direction. However, the spindle rotates at a higher speed than the traveller.

If both rotate at the same speed, only the twisting of yarn takes place without winding. Due to the

difference in their rotational speeds, the winding of the yarn takes place on the cop.

Length of yarn wound on the cop per min = πd (NS –NT)

Due to rotation, both spindle and traveller insert twists onto the yarn. If both the spindle and traveller

rotate in a clockwise direction, a ‘Z’ twist is inserted to the yarn.

Turns/cm in the yarn = NT/πd (NS –NT)

The winding rate should be equal to the delivery rate.

Length of yarn delivered (cm/min) = πd (NS –NT)

Here winding takes place in similar conditions to when the traveller is stationary and the spindle is

rotating; hence winding does not insert any twist onto the yarn. On the other hand, during over-end

unwinding one turn of twist is inserted for every unwound of coil.

Turns/cm for unwinding = 1/πd

Total twist present in the yarn after over-end unwound = NT/πd(NS –NT) + 1/πd = NS/πd(NS-NT)

Since yarn from the ring cop is normally over-end withdrawn during the winding process, the spindle

speed is taken for calculating the turns/cm in the yarn instead of using traveller speed

Selection of TM for various count

Count and TM:

Count (Ne) – Woven yarn TM (Twist Multiplier)

10-20 4.6-4.8

20-40 4.4-4.6

40-60 4.2-4.4

60-80 3.8-4.2

Above 80 3.6-3.7

Knitted Yarn: 3.6-3.8 (generally

We know,

TPI = TM√ Count (for indirect system)

TPM = TM/√Count (for direct system)

πDrNt

Traveller Speed:

The speed by which traveller rotate around the ring is given by the formula

= m/min

Since traveller does not have a drive on its own but is dragged along behind by the spindle. High contact

pressure (up to 35 N/ mm2)is generated between the ring and the traveller during winding, mainly due

to centrifugal force.

This pressure leads to generation of heat. Heat produced when by the ring traveller is around 300

degree Celsius. This has to be dissipated in milliseconds by traveller into the air.

Low mass of the traveller does not permit dissipation of the generated heat in the short time available.

As a result the operating speed of the traveller is limited.The maximum attainable speed of traveller

without getting damaged is known as “Limiting Speed of Traveller”.

70 ft/sec. (22 m/sec) – Conventional Ring- traveller.

120 ft/sec. (35 m/sec) – H.S. Ring- traveller.

Unit -3

Winding

3.1Building motion mechanism, insertion of coil on bobbin. Yarn ballooning, yarn ballooning

control rings, separators, lappets

Building Motion Mechanism

https://youtu.be/Xt1cYghDrg

Link for Winding mechanism

TYPES OF BUILDING MOTION:

Building motion of ring frame is possible in a number of ways depending upon the

cam shape. Cam shape governs the locking ratio Which is the Speed ratio of

Upward & downward motion of ring rail.

COP build (heart shaped cam)

Locking ratio 1:33- 1:4

Speed of upward traverse is much slower than downward traverse depending upon the

locking ratio.

In cop build the length of yarn in upward traverse is more than downward traverse.

Lift is normally equal to ring diameter + 4-5mm

Fast rate of unwinding

Builder Motion

Fig.4 shows different parts of a typical builder mechanism used in ring frame. The ring rail is suspended by belts from a disc mounted

on the shaft; the full weight of the rail is carried by the disc and generates a turning moment. At the other end of the shaft there is

another disc; this second disc, acting via the chain and chain drum, presses the level with the roller against the heart shaped eccentric.

Owing to the rotation of the eccentric, the lever and the chain drum are continually raised and lowered. This movement is transferred

to the ring rail by way of the discs together with the chain and belt, thus giving the traverse movement.

Each time the lever moves down, it presses the catch to release the ratchet wheel, which enables a slight rotation of the drum

connected to the ratchet wheel. A short length of chain is thus wound up on the drum. This leads to rotation of the disc, shaft, and disc

(b), and finally to a slight rise in position of the ring rail – the lift.

The shaft also carries a third disc from which the balloon control rings and lappets are suspended by belts. These are

correspondingly raised and lowered, but since disc C is slightly smaller than disc (b), the stroke length is somewhat shorter.

Building the Base (Fig. 5)

The base of the cop is curved on its exterior in order to enable as much yarn as possible to be taken up on the package. This

curvature arises partly from the specific type of winding itself, but is significantly reinforced by a mechanical auxiliary

mechanism – the cam (N in Fig.5), thumbs, deflector device or whatever other name the mechanism carries.

As already explained, raising and lowering of the ring rail comes about because the eccentric moves the lever up and down

thus the disc is continually turned alternately to the left and to the right. Disc carries the cam, which projects beyond the

periphery of the disc and thus forms a lobe of larger diameter than the rest of the disc.

At the start of winding of cop, disc is located in the position shown in figure. In which the lobe noticeably deflects the chain.

The effect of this deflection is that the chain elongation upon rising of the lever is not wholly transferred to the ring rail; part is

lost as deflection at N. The traverse stroke of the ring rail is no longer corresponds to the setting, since it is shorter.

However, since the length of yarn delivered during each traverse stroke is the same, the volume per layer is increased, thereby

generating the curvature.

Now, in the further course of the spinning operation, the chain take-up disc (T) is steadily turned to the left in small steps by

the ratchet wheel; the chain is thereby wound up on the disc and thus shortened.

Accordingly, disc (a) turns to the right in the same small steps and the cam is carried out of line with the chain; finally, the

complete elongation of the chain is passed on to the ring rail and thereafter the cop takes its

What Is Yarn Ballooning ?What Are The Factors, Which Effect The Degree Of Ballooning And How Can Be

Controlled?

During spinning operation the drafted strand of fibre being delivered and held at one end by the front

rollers, the other end rotates round the bobbin with the traveller on the ring. It is observed that the

thread between the thread guide and the traveller, is bulged out which is called the ballooning effect if

the thread; and the balloon runs around the bobbin at a high speed equal to the speed of the traveller.

The following factors effect the degree of ballooning –

The weight of the balloon length – The length of the yarn which shows the ballooning effect is called the

balloon length. The degree of ballooning varies inversely as the wt. of the balloon length i.e. higher the

balloon length-weight, smaller the balloon size.

Yarn count – The degree of ballooning varies directly with the yarn count i.e. higher the yarn count,

lighter the yarn and higher the balloon size.

Speed of the traveller – Higher the speed of the traveller, larger the balloon size.

Weight of the traveller – Lighter the traveller, larger the balloon.

Atmospheric resistance surrounding it – Higher the resistance, smaller the balloon.

Frictional resistance at the thread guide and at the traveller against the passage of the thread – Higher

this resistance, smaller the balloon size.

The effect of item no. 5 and 6 is little on ballooning. The following measures may be taken to control the

ballooning –

The use of correct traveller size.

The use of correct traveller speed.

The use of separator or balloon guards between the two rings.

By lowering the thread-guide rail to the correct position.

Yarn Balloon controlling Rings

Balloon control rings are used to contain the yarn-loop, by reducing the yarn tension and decreasing the

balloon flutter instability. Flutter instability here refers to the uncontrolled changes in a ballooning yarn

under dynamic forces, including the air drag. Due to the significant variation in the length and radius of

the balloon during the bobbin filling process, the optimal location for the balloon control ring is not

easily determined. In order to address this difficulty, this study investigates the variation in the radius of

a free balloon and examines the effect of balloon control rings of various diameters at different

locations on yarn tension and balloon flutter stability. The results indicate that the maximum radius of a

free balloon and its corresponding position depend not only on the yarn-length to balloon-height ratio,

but also on yarn type and count. A control ring of suitable radius and position can significantly reduce

yarn tension and decrease flutter instability of free single-loop balloons. While the balloon control rings

are usually fixed to, and move in since with, the ring frame, results reported in this study suggest that

theoretically, a balloon control ring that always remains approximately half way between the yarn-guide

and the ring rail during spinning can lead to significant reduction in yarn tension.

Separators

Separator is an aluminium or plastic plate, which is placed between the individual spindle to prevent the

hurled of broken thread to neighbouring yarn making balloon. Most this ends down arise from breaks in

the spinning triangle, because there very high forces are exerted on a strand consisting of fibres which

have not yet been fully bound together. If a break occurs in the triangle, then the newly created free

yarn end must be drawn to the cop and wound onto it.The broken end lashes around the spindle. In

absence of any protective device this broken yarn would hurled into the neighbouring yarn balloon and

thus causing ends breakage on that spindle also. This process will continue and a wave of end breakage

will travel in a row of spindles. To prevent this multiple breakages separator are used.

Lappets:-

Lappet consists of thread guide and an arm. This thread guide lead the yarn centrally over the

spindle axis and arm fix at lappet rail. The main function of the lappets is to maintain the balloon size

within the controlling range. To keep the balloon length within the controlling limit, the lappets has to

traverse relative to the ring rail. For 8” lift bobbin the traverse of the ring rail is more or less confined

within the range from 1” – 1.5” and higher traverse for higher lift of the machine.

The slow traverse of lappet-rail also facilitates the easy passage of the yarn from the front roller to the

bobbin.

3.2 Reasons for end breaks and their remedies on Ring Frame.

https://youtu.be/TUJy_UVG0jE

Link for end breakage control in Ring frame

Bad skewer ends or tips or any other fault which prevent the free rotation of the roving

bobbin.

Traverse guide when collecting fly blocks the regular passage of the roving.

No middle traverse guide when using double roving.

Bad piecing in the roving.

Stretched roving.

Irregular roving.

More twist applied in the roving leading to “shedding through” at the ring.

Single roving when using double.

Neps or slubs in the roving.

More waste in the roving.

Incorrect break draft.

Roller lapping.

Worn or grooved roller.

Rust on the bobbin drafting.

Worn aprons.

Pneumatic system does not work properly so that the drafted strand of fibres fly entangles

with the side end and cause breakage.

Irregular distribution of draft in the drafting zones.

Incorrect weight distribution on the top roller.

Improper weighting of the top roller.

Incorrect setting of the drafting rollers in relation to the average staple length of fibres under

processing.

Incorrect setting of the lappet is not at the straight line with the top of the spindle.

Dwell at each end of the traverse of the lappet rail.

Starting up of the m/c when the lappet rail is at the top position.

Worn ring.

Grease or gum on and under side of the ring flange.

Heavy or lighter traveller than that required for the count.

Worn traveller.

Traveller flying off.

No traveller clear creating tufts of fibre on the traveller.

Lack of lubrication in the bolster cage or insert.

Bent spindle is out of centre of the spindle.

Excessive spindle speed than that requires for the count.

Obstructed spindle speed by accumulation of fibres beneath the spindle.

Too larger or smaller diameter of bobbin than that suitable for the count.

Jumbling bobbin.

Vibrating bobbin.

Badly worn bobbin in which yarn tends to catch at the starting up.

Excessive full bobbin which rub against the ring.

Bad joining of tapes causing spindle vibration.

Tap ends flying off due to badly sewing.

Slipping tapes.

Use of higher or lower twist multipliers than that requires for the count.

Flying fibres.

Incorrect relative humidities.

Wind in the spinning section.

Bad piecing up of the yarns.

Shorter staple when used for higher count.

Immature short or broken fibres in the sliver.

Weaker fibres.

Improper lubrication of the m/c.

Lack of proper cleaning of the m/c floor.

Irregular maintenance and over haul.

3.3 Principle of Auto doffing at Ring Frame

https://youtu.be/M9tuAvDVgZM

Link for Auto doffing in Ring frame

Automatic doffing

There are two types of automatic doffing for ring-spinning machines: stationary and

travelling devices; the former is mostly used in new machines. After completion of a

doff, the doffer, which contains empty ring bobbins and also the provision for holding the

fully wound bobbins, rises from below. Fully wound cops are then gripped by the doffer

and transferred to it, and then empty bobbins are transferred from the doffer to the

spindle of the ring-spinning machine. Subsequently the doffer comes back to its original

position and transfers all the full cops to a conveyor belt, which might be used to

transfer them to the winding machine. Automatic ring frame doffing has been widely

accepted and the most common system involves rails that reach from end to end of the

frame. These rails are designed to carry the full bobbins during the doff, and the empty

ones during the replenishment phase. The doffer rail carries apertures for each spindle

and each spindle is equipped with a grasping device. The grasping device is often an

inflatable cuff which fits over the bobbin and grasps it. The purpose is to lift the full

bobbin from the spindle without damaging the yarn. Two series of pegs are mounted on

a belt running the length of the machine. One series of pegs carries empty bobbins

which have been mounted before the start of the doffing sequence. The ring frame is

stopped automatically when the bobbins are full, then: (a) the ring rail is lifted clear after

the ends of yarn have been trapped at the base of the spindle; (b) the doffing rail is

dropped over the full bobbins; (c) the grasping devices are activated and the rail is used

to lift the full bobbins from the spindles; (d) the full bobbins are deposited on the vacant

pegs on the belt just mentioned; (e) the doffing rail then picks up the empty bobbins

from the belt; and (f) the rail deposits these empty bobbins on the empty spindles. On

start-up, the yarns should still be threaded through the travellers and the rotating

bobbins should catch the yarn and start spinning automatically. In practice, a few ends

fail to catch and have to be pieced manually. Thereafter, the belt moves towards the

end of the spinning machine and the full bobbins are either removed or continue on to

the winder. When the bobbins are transported directly from the auto doffer to the winder

without human intervention, it is known as ‘linked spinning’.

3.4 Principle of variable pulley speed at Ring Frame

3.5 Workload distribution at Ring Frame

In the competitive yarn market it is most essential for the Spinning mills to have optimum work

load of the worker. If worker is overloaded then it will cause fatigue to him, he will not perform

all the work allotted to him. Like his end breakage attending time will increase or he will skip

m/c part cleaning. This will lead to quality detoriation which is also not tolerated. Also with less

work load mills can not survive. In modern mill work load in Ring frame department is as

follows. This is for 1008 spindle m/c.

Sider -3 sides of 20s count

- 4 sides for 21s to 30s count

-5 sides for 31s to 40s count

- 6 sides for 41s to 50s count

Worker has to clean drafting zone of m/cs

He has to timely attend end breakage of m/c.

Work load of doffers is 5000 to 6000 bobbins per doffer in manual doffing m/cs.Doffers have to

clean other parts of m/c as per system developed by mill.

One Jobber has to look after 50000 spindle.

4 Helper for 50000 spindle. They have to lead doffers and responsible for doffing time, gaiting

in m/c and cleaning of allotted m/c part.

One cleaning boy for floor cleaning.

3.6 Gearing diagram of Ring Frame.

Practice of drawing gearing diagram of RingFrame

3.6.1 Calculation of spindle speed and Front Roller speed of Ring Frame and calculation of

production of machine per shift.https://youtu.be/5i68nEVPYMs

Link for gearing diagram and various calculations

Spindle Speed = 6095.24 rpm

Front roller delivery = 323.56 inch/min

Fig: Gearing diagram of a Ring Frame

Speed calculations

223 26 83 72 30 103 26

(i) speed of front roller = 1440 x -------x ------- x -------- x ----------- x -------- x --------- x ---

--------

404 115 82 65 47 102 29

= 124.37 rpm

Production calculation

πDN × 8 × 60 × 95

Production/shift/machine = --------------------------------------

TPI × 36 × 840 × 2.204 × 100 × count

π × 1.062 × 124.37 × 8 × 60 × 95

= ------------------------------------------------

36 × 840 × 20 × 2.204 × 100

= 0.1419 × 64 = 9.0847 kg/shift/machine

3.6.2 Calculation of total draft, break draft And individual zone draft.

Draft constant

Total draft = ---------------------

DCW

(iii) To find draft constant

Surface speed of front roller

Draft constant = --------------------------------------------------

Surface speed of back roller

Assume front roller speed = 1 rpm

Draft change wheel = 1

π × 27 × l

Draft constant = ---------------------------------------------------------------------------------------

π × 27 × l x 29/26 x DCW/103 x 20/112 x 21/47

Draft constant

(iv) Total draft = ---------------------------

DCW

1218.30

= -----------------

70

= 17.4

Surface speed of front roller

(i) Front zone draft = ------------------------------------------------------

Surface speed of middle roller

π x 27 × 124.37

= -----------------------------------

π × 27 × 10.667

= 11.3166

Surface speed of middle roller

(ii) Back zone draft = -----------------------------------------------------

Surface speed of back roller

π × 27 × 10.99

= --------------------------------

π × 27 × 7.522

= 1.467

Spindle Speed x 60 x 24 x Total no of

Spindles = ……………………………………………......

Count x TPI x 840 x 36 x 2.2046 .

Surface speed of middle roller

Back draft = -----------------------------------------------------

Surface speed of back roller

π × 27 × 10.99

= -----------------------

π × 27 × 7.522

.= 1.467

Draft calculations

Surface speed of front roller

(i) Front zone draft = -----------------------------------------

Surface speed of middle roller

π x 27 × 124.37

= ------------------------

π × 27 × 10.667

= 11.3166

Surface speed of middle roller

(ii) Back zone draft = ---------------------------------------------

Surface speed of back roller

π × 27 × 10.99

= ------------------------

π × 27 × 7.522

= 1.467

3.6.3 Calculation of twist per inch and Twist Multiplier.

Spindle speed

Twist per inch = ---------------------------------

Front roller delivery

9462.51

= --------------------------------------

π x 27/25.4 x 124.37

= 22.78

_____

Twist per inch =TM√ count

or TM = TPI here yarn count is taken 36.

√count

= 22.78

√36

= 22.78

6

= 3.79

3.6.4 Calculation of production constant, draft constant, break draft constant and twist

constant.

Spindle Speed x 60 x 24 x Total no of Spindles

= …………………………………………

Count x TPI x 840 x 36 x 2.2046

(iii) To find draft constant

Surface speed of front roller

Draft constant = --------------------------------------------------

Surface speed of back roller

Assume front roller speed = 1 rpm

Draft change wheel = 1

π × 27 × l

Draft constant = ---------------------------------------------------------------------------------------

π × 27 × l x 29/26 x DCW/103 x 20/112 x 21/47

Draft constant

(iv) Total draft = ---------------------------

DCW

1218.30

= -----------------

70

= 17.4

Break Draft constant

Calculate speed of middle roll assuming back roll rpm 1

=47×32

21×BDCP

= 71.61

BDCP

Calculation of twist constant

Twist constant = Spindle speed

Front roll speed with putting value of Twist change gear.

3.6.5 Calculation of traveller speed

Traveller speed is calculated by finding surface speed of traveller in meter per second.

By assuming sum data.

Let spindle speed is 19000 rpm

Rlng diameter 40 mm.

Here we consider air drag nil

Now traveller speed=π×D×N

= spindle speed×π×D

60×1000

= 19000×3.14×40

60×1000

=39.77 metre/min

3.6.6 Calculation of yarn content on bobbin

Yarn content of bobbin can be calculated by assuming some data

Suppose time to come doff in m/c is 35 min, front roll speed is 50 metre per minute,

count running on m/c is 20 s.

Now production in metres of 35 min. will be =35×50mt. =1750

=1750×1.09 yards

Now yarn content in bobbin

=1750×1.09 in lbs(pound)

840×count

=1750×1.09×1000 grams

840×count× 2.205

= 52 gms

Winding:

The yarn is rotated on bobbins which are fixed on spindle and due to this rotation, balloon is

formed. The balloon formed on one spindle can be entangled with the balloon formed on the

other spindle. To overcome this problem, separators are used which avoid the entanglement of

balloons. The yarn is wound up onto a cylindrical cop form by raising and lowering of the rings

which are mounted on a continuous ring rail.

Fig: Winding in ring frame

Doffing:

It is the final process of ring frame. Doffing is a process to replace an empty bobbin at the place

of fully wound bobbins.

Advantages of Ring Frame:

Any type of material (fibre) can be spun.

Wide range of count can be processed.

It delivers a yarn with optimum characteristics.

Idealized twisting system.

It is uncomplicated and easy to operate.

Higher yarn strength can be achieved.

Disadvantages of Ring Frame:

Production rate is low.

This machine works as more heat generates

Unit No -4

Doubling

4.1 Objects of Ring Doubling, Doubling, and its effects, dry and wet systems of doubling

https://youtu.be/_xzKNg1gmlw

Link for ring doubling m/c

Study on ring doubling frame

Spindle speed, front roller delivery.

Twist, twist Constant.

Objects:

To combine two or more single threads into one.

To insert sufficient amount of twist for holding the yarns.

To increase strength, smoothness and lustre.

To reduce hairiness.

To make sewing thread.

To wind a suitable bobbin.

Main parts:

Creel stand and creel.

Front roller.

Yarn guide.

Ring and ring rail

Tin cylinder.

Traveller.

Thread weight or slip roller.

Lappet Spindle.

Doubling and it’s effect:-

Jeans sewing thread

Type Cord

Cable yarn

Cutting yarn

Dry and wet system of Doubling

There are two systems of doubling namely, wet doubling system and dry doubling

system. Wey doubled yarns are harder, stronger and more wiry. Due t wetting the

protruding fibres get tucked in during the operations and hence these yarns are much

less hairy.

Wet Doubling Systems:

The different types of wet doubling system English system of wet doubling, Scotch

system, American system, Modified stock port and Nottingham threading.

English System of Wet doubling:

Fig-English Wet Doubling system

English system the yarn from the creel is made to pass under glass rod immersed in

water trough. The yarn is then directed to a system of a pair of delivery rollers and

finally led to twisting zone. Water taps are situated at one of the ends of trough, similarly

there is also a drain pipe provided at the bottom of through to run the water off, an

arrangement is also provided for lifting the immersed glass rods. This facilitates easy

cleaning of trough. The delivery rollers are two inches in diameter and are brass coated.

The yarn after passing through the water through gets wet. The weight of the top roller

effects the squeezing action on the wet yarn, this action squeeze excess of water it also

helps the water to penetrate the body of the yarn.

Dry doubling

The usual ring doubler resembles very closely to the ring frame and the twisting and the

winding mechanism are more or less similar to that of ring frame. The creel in doubling

zone is modified to take cones, cheese and the thread guides are provided to guide the

yarn to the delivery roller. In doubling frame only one pair of delivery roller is required

because there is no drafting. The following figure shows passage of yarn through

doubling frame.

4.2Twist insertion in ply yarn, types and amount of

twist. Factors effecting the multiplier for double yarn

https://youtu.be/XtO0Sjo-OU8

https://youtu.be/4Bqz5HHRDkc

Link regarding plying and twisting

Twisting, in yarn and rope production, process that binds fibres or yarns together in a

continuous strand, accomplished in spinning or playing operations. The direction of the

twist may be to the right, described as Z twist, or to the left, described as S twist.

Single yarn is formed by twisting fibres or filaments in one direction. Ply yarn is made by twisting two or more single yarns together, usually by combining singles twisted in one direction with a ply twist in the opposite direction. Twine, cord, or rope can be made with a cable twist, each twist in the opposite direction of the preceding twist (S/Z/S or Z/S/Z), or with a hawser twist, the single yarns and the first ply twist in one direction and the second ply twist in the opposite direction (S/S/Z or Z/Z/S). The number of turns per unit of length in a yarn affects the appearance and durability of fabric made from that yarn. Yarns used for soft-surfaced fabrics have less twist than those used for smooth-surfaced fabrics. Yarns made into crepe fabrics have maximum twist.

Ply-twisting has a beneficial effect on the tensile characteristics of ring spun yarn and it

is only necessary to use 60–70% of the ply-twist ofequivalent ring spun yarns.

Factors effecting multiplier of double yarn :-

1. Type of end use.

2. Strength requirement in doubled yarn.

3. Feel requirement in the resultant product.

4. Requirement of twist effect in the fabric.

5. Twist given in single yarn.

4.3 Yarn defects and their causes and remedial measures in doubling machine

https://youtu.be/Zjm0gXTlCGI

Link regarding yarn defects in doubling m/c

1 Oil stained yarn. This is due to oil on some part of m/c.Can be avoided by keeping proper

cleaning of m/c and avoiding any leakage of oil in m/c.

2.Snal in doubled yarn. It is due to giving excessive twist in doubling. Proper selection of twist

factor in doubling can avoid it.

3.Wrong type of twisted yarn. Ply of single and doubled yarn not checked properly.

4 Single yarn at some place. It is due to missing of one end in the doubled yarn due to end

breakage or exhaustion of supply package. Reason faulty stop motion. Can be avoided by

repairing yarn stop motion.

5.To loose or tight doubled yarn package. It is due to improper tension during doubling. Can be

rectified by proper selection of yarn tension during doubling.

6 Sloughing off of yarn. Due to improper selection of yarn doubling parameters or faulty

winding mechanism. Corrected by selecting proper parameters or rectifying defective winding

mechanism.

4.4 Improvement in quality and productivity performance of a doublingmachine

A higher evenness of the resultant yarn due to doubling;

Improved dynamometric properties due to doubling, the better utilization of basic fibre properties, and more axial fibre

orientation;

Higher stability against wear during subsequent processing and later use, owing to a more effective binding of surface

fibres into the bulk mass of the yarn;

Elimination of spinning torque by a balancing of the stresses within the structure;

Higher yarn volume and a resultant improvement in fabric cover due to the modified fibre arrangement; and

Modified specific handle and visual appearance

Folded yarns are favoured for application in shirting fabric, suiting materials, premium denim fabrics, fabrics for work clothes,

sportswear fabrics, sheeting fabrics, upholstery fabrics, velvet fabrics, and terry toweling. The object is to achieve structural

stability against extension, resistance against wear, fabric cover or higher moisture absorption. All sewing threads from staple

fibres or mixed compositions (core yarns) have to be plied in order to achieve the desired binding of the surface fibres and the

necessary stress-strain characteristics. Here the need for ply-twisting is undisputed. Tyre-cord yarns are always folded,

normally with very high but balanced twist.

Folded yarns for use in cotton voile or crepe fabrics, which have a tight structure and pronounced grainy appearance, are ply-

twisted in the same direction as they were spun. Such yarns display high extensibility and elasticity and good recovery after

high elongation.

DIRECTION OF TWIST

Staple-fibre yarns are normally ply-twisted in the direction opposite to their spin twist, which thus yields low or zero twist in

the resultant composite yarn. Yarn cohesion and strength depend not only on fibre migration and fibre twist but merely on

wrapping strands around each other. The almost-parallel arrangement of fibres in the yarn leads to a better utilization of fibre

properties. A more open yarn structure is produced yielding a higher specific volume. A reduction in unidirectional torque

produces a reduction in snarling and spirality.

Folded-yarns are also produced by ply-twisting in the same direction of spin-twist. With this arrangement the folding twist is

additive to the single strand twist, giving a compact yarn suitable for crepe yarns and bold striping threads. These yarns are

very twist-lively and must be stream-set in an autoclave. The folding operation always causes a length contraction; therefore

the single yarns must be spun finer than the normal count.

https://youtu.be/O7Gb5rOBxe04.

Link regarding TFO M/c

5 Working principle of TFO

Two for one twister, introduced some sixty years ago for filament twisting, has now gained greater

use for ply twisting of both spun yarn and filament yarn sectors mainly because of their inherent

advantages like (1) production of long length of knot free yarns which facilitates better performance in the subsequent processes and (2) higher productivity. This system is suitable for all types of

yarns, except very fine yarns (above 80 s count), produced from all types of fibres.

Now-a-days, TFO twisters are gaining world-wide acceptance in Figure 1 shows the passage of yarn in two for one twister from a

doubler package to winding package. Traditionally, ring doublers were used for ply twisting spun yarns and uptwisters were used for

twisting filament yarns. Now-a-days, TFO twisters are gaining world-wide acceptance in both spun yarn and filament yarn sectors mainly

because of their inherent advantages like (1) production of long length of knot free yarns which facilitates better performance in the

subsequent processes and (2) higher productivity.

Principle

The yarn unwound from the feed package goes to the snail wire through the tensor, inside the spindle and outside the rotary disc. The

yarn receives its first twist between the capsule and the bending part and the second turn between the bending part and the snail wire

thus obtaining two twists with one rotation of the spindle.

Figure 1 : Material passage in two for one twisting

An assembly wound package (i.e. two yarns assembled onto one package without any twist) is usually used as the stationary supply

package. The supply yarn is threaded through a guide mounted on a freely rotating flyer and then passes through the hollow rotating

spindle. At the base of the spindle, the yarn comes out forming a balloon, and then goes onto the winding head via the yarn guide.

Each rotation of the spindle will insert one turn of twist in the length of yarn within the spindle, plus another turn of twist in the yarn

balloon. As a result, two turns of twist are inserted into the yarn for each rotation of the spindle, hence the name two-for-one twisting.

4.6 Gearing diagram showing various drives of a Ring Doubling Machine

4.6.1 Calculation of production per machine, production constant

4.6.2 Calculation of spindle speed, delivery Roll speed.

4.6.3 Calculation of twist per inch/twist Multiplier and twist constant of the Machine

Calculation

Specification:

Motor rpm = 1430

Motor pulley diameter = 6.25²

Machine pulley diameter = 10.25²

Tin cylinder diameter = 10²

Wharve diameter = 1.37²

Cylinder carrier wheel = 24T

TCP carrier wheel = 62T

TCP = 63T

Front roller diameter = 2’’

Unit -5

General Calculations

5.1 Calculation of different types of yarn’s diameter

https://youtu.be/4I6GcXue5T0

Link for calculation of yarn diameter

Yarn Diameter:

Although yarn count serves the purpose of defining yarn fineness, i.e., yarn diameter for

general textile processing, sometimes it is essential to calculate the exact diameter of

the yarn.

Calculation of yarn diameter is specially needed in the following cases:

To set slub catcher or yarn clearer in winding.

To determine beam width, reed count, etc., in warping, sizing and weaving.

To decide number of threads per inch in cloth.

To decide needle size or machine gauge in knitting.

To study fabric geometry.

Considering the importance of yarn diameter, attempts were made to establish the

relationship between diameter and count of yarn. In this respect, the pioneering work

of Pierce is praise worthy. As derived by him, the approximate diameter (d) of cotton

yarn,

d in inch = 1/{28 × √(count)}

or d in mm = 0.0037 × √(Tex)

For the purpose, he assumed specific volume of cotton yarn as 1.1 (i.e., 1.1 c.c. of

cotton yarn weighs 1 g)

Finding the diameter of a given count of yarn:

The diameter of a yarn can be found out by extracting the square root of the total

yards in a pound of the given count and then subtracting 10 per cent from the result.

The yarn diameter in inch is the reciprocal.

For example: Find out the diameter of a 46s yarn.

Yards in a pound (840 x 46)

Square root 166.6

Less 10% 177.0

Hence the diameter 1/177 inch

In other words, if 177 threads are laid side by side they occupy one inch

Diameter of yarns vary as the square root of the yarn counts

Thus the diameter of 36s is 1/157 inch

And 16s is 1/104 inch

This can be shortened in a simple equation as bellows

Diameter per inch (cotton/spun silk) = √(yards per pound) - 10%

= 0.9 √yards per pound

= 26.1 √count

This calculation of yarn diameter is very useful particularly in weaving for determining

the optimum ends and picks per inch. Intersections of warp ends for weft threads and

weft threads for warp have to be carefully considered. This is also useful for finding

ends and picks while changing from one count to another, for finding the counts in

changing from one number of threads per inch to another number of threads per inch

and for finding ends and picks per inch in use and in changing from one pattern to

another.

Find out the diameter of 20s count of yarn.

Solution:

Diameter per inch = √ ( yards per pound) - 10%

Here yards per pound = (20 x 840)

So, now

Diameter per inch = √(yards per pound) - 10%

= √ (20 x 840 ) - 10%

= 118 per inch

5.2 Calculation of balancing of machines in different sections for a particular spin plan

requirement.It is given at the end of file.

Unit -6.

Sequence of machinery used in the production of woollen yarn and worsted Yarn and

theirbrief description

6.1 Woolen System:--Woolen system is entirely a different system of yarn manufacturing then

other system of yarn manufacturing in to yarn produced.

1 With simplified flow system.

2 Fewer manufacturing processes.

3 Low draft level causing less fibre orientation and resulting in bulky and fuller yarn.

4 The fibres are randomly oriented and are not in parallel form, they are in crisis cross fashion

and intertwined when reaches the spinning process. The fibres are trapped in this position with

insertion of twist, creating air pocket in yarn and more fibre standing out on the surface of yarn.

This increases volume per unit weight of yarn.

Process Flow

Shearing---Sorting and grading----Scouring--Drying—

Oiling--Carding--Spinning (Woolen Yarn)

1 Shearing:-

Sheep are sheared once a year— usually in the springtime. A veteran shearer can shear up to

two hundred sheep day. The fleece recovered from a sheep can weigh between 6 and 18

pounds (2.7 and 8.1 kilograms).

2Sorting and Grading:-

Grading is the breaking up of the on quality. In sorting, the wool is broken up into sections of

different pans of the body. The best quality of wool comes from the shoulders and is used for

clothing.

3 Scouring:-

Scouring involves the use of hot water detergents to remove soil, vegetable impurities, grease

and other contaminants fibres. Wool scouring typically uses water and alkali. Although scouring

with an organic solvent is also possible. Scouring with alkali breaks down natural oils surfactants

and suspends impurities in the bath.

4 Drying

After the wool has been scoured, it is dried before passing it on to next of manufacturing

process. . The modern process of drying stock with heat.

5. Oiling:-

•Wool oiling is the removal of natural. preservative greasy matter or yolk.

•It is necessary to lubricate the fibres of wool with oil before carding and spinning, in order to

preserve the serrations of the fibre from injury during the card process.

•Imperfect oiling results in gummed-up cards, uneven work, and also in destruction to a

greater or less extent of the elasticity of resultant yarn.

6 Carding:-

Operation is intended to disentangle the fibres and lay them as parallel as possible. The fibres

are passed through rollers covered with fine wire teeth.

Functions of Carding

Opening of individual fibre.

Elimination of impurities & dust.

Removing of neps.

Fibre orientation

Sliver formation

7 Roving:-

The roving as it comes off the card has no twist. It is held together by the oil and natural hooks

that exist on the surface of the wool fibres. Roving is actually a light twisting operation to hold

the thin slubbers intact. The fibre passes between the roller, over the coarse wire teeth of the

first card clothing & over progressively finer toothed card clothing.

8 Spinning:-

The spinning frame will put the actual twist on the roving and turn it into yarn. This is collected

on wooden bobbins. The frame we have is small but it can spin up to 90 threads at one time.

9 Winding or Skinning:-

When the wooden bobbins are full of yarn, they are placed on a cone winder and the yarn is

transferred to paper cones use in weaving and knitting machines. It could also be put into

skeins of yarn.

6.2 Worsted system:- In the manufacturing of worsted yarns, the different steps involved

are,

Shearing.

Sorting and Grading.

Scouring

Drying

Oiling

Carding

Gilling and combing

Drawing

Roving

Spinning

In this process steps of Shearing, Sorting and Grading, Scouring, Drying, Oiling are similar to

Steps discussed for Woollen System.

Carding:

The carding process for worsted yarn production is intended to disentangle and lay them as

parallel as possible. The fibres are passed between rollers covered with fine wire teeth. Since

worsted yarns, however, should be smooth, the fibres are made to lie as parallel as this process

will permit. Following this operation, the wool goes to the gilling and combing processes.

Gilling and Combing:

Gilling is carried out before (preparative gilling) and after (finisher gilling) combing. The

preparative gilling is mainly to align the fibres in a parallel direction, further blend the wool

through doubling and to add moisture and lubricants. Whereas finisher gilling is mainly aimed

to remove the mild entanglement introduced to the combed sliver. The carded wool, which is

to be made into worsted yarn, is put through gilling and combing operations. The gilling process

removes the shorter staple and straightens the longer fibres. This process is continued in the

combing operation, which removes the shorter fibres of 1 to 4 inch (25 – 100 mm) lengths

(called combing noils), places the longer fibres (called tops) as parallel as possible, and further

cleans the fibres by removing any remaining loose impurities.

Drawing:

Drawing is an advanced operation which doubles and redoubles slivers of wool fibres. The

process draws, drafts, twists, and winds the stock, making the slivers more compact and

thinning them into slubbers. Drawing is done only for worsted process.

Roving:

This is the final stage before spinning. Roving is actually a light twisting operation to hold the

thin slubbers intact.

Spinning:

The type of spinning explained here is applicable both for woollen and worsted yarns. In the

spinning operation, the wool roving is drawn out and twisted into yarn. There are two main

methods used to produce woollens-spun yarns. These are:

Ring spinning

Mule spinning

Mule-spun yarns generally are superior to ring-spun yarns but they tend to be much more

expensive due to the slow production rates and high labour input.

Worsted yarns are spun on any kind of spinning machine – mule, ring, cap, or flyer. The two

principle systems of spinning worsted yarns are the English system and the French system.

In the English system (Bradford), the fibre is oiled before combing, and a tight twist is inserted.

This produces smoother and finer yarns. The more tightly twisted yarn makes stronger, more

durable fabrics.

In the French system, no oil is used. The yarn is given no twist; it is fuzzier, and therefore

suitable for soft worsted yarn.

https://youtu.be/1pGqM9Wot24

https://youtu.be/LdHViafQA5E Link for worsted spinning

6.3 Difference between Woolen &Worsted yarn

Woolen Processing Worsted Processing

Spun from wool fibres of:

Length : spun from short fibres of 1-3”

Diameter: medium or coarse

The fibres are washed, scoured and carded.

Spun from wool fibres of:

Length : longer than 3”

Diameter: fine diameter Fibres are washed, scoured,

carded, combed and drawn

Yarn Yarn

Bulky

Uneven

Low to medium slack twist Tensile strength lower than worsted

Fine

Smooth

Even

Tighter twist Higher tensile strength

Fabric Appearance

Soft Fuzzy

Heavier weight

Fabric Appearance

Crisp

Smooth

Lighter weight

Characteristics

Insulator due to trapped air Does not hold a crease well Less durable than worsted

Characteristics

Less insulator Holds creases and shape

More durable than woollens

Uses

Sweater Carpets

Tweeds

Uses

Suits

Dresses

Gabardines

Crepes

https://youtu.be/dtiOOXGWGg

Link for comparison of woollen and worstedspinningsystem

Unit -7

Maintenance

7.1 Various maintenance schedule adopted in a frame.

https://youtu.be/FlZHy8nfbcM

Link regarding cleaning and maintenance of ring frame

To reduce down time and to achieve better quality of yarn it is at most important that proper

preventive schedule should be followed for Ring frame machine. Following are the benefits of

preventive maintenance.

1.It reduce m/c down time.

2.It improve life of m/c parts.

3.Working performance improves.

4.Cost saving

5.Improve yarn quality and maintain consistency in quality.

6.Higher productivity can be achieved due to better working of m/c.

7.Defective quality material can be minimize.

8.Early detection of any fault in m/c or quality.

Ring change schedule - 3 years

Front cots to change if shore hardness increases from 65° to70°

Machine levelling after 3 years

Pneumafil duct cleaning in every cleaning.

Hose pipe checking and if required replacing for pressure leakage in every general cleaning.

Spindle change after 10 years

Top arm change after 10 years.

Unit -8

Process control Parameter with reference to productivity and

yarn quality

https://youtu.be/bp_7ftKmHOg

Link for quality improvement in yarn

Changes are taking place very fast all over the world in all fields, such as

technological developments, the living styles, social environment, and the

perception of people. In this changing scenario, rising expectations of the customer

and open market economics are forcing businesses to compete with each other.

Therefore, basic quality of the product at competitive market price is a key factor.

The same holds good for textile industry also which is one of the oldest and has a

number of players all over the world. Today textile industry is facing higher

competition in the globalized market than ever before. When it comes to textile,

spinning is the key process, which has been given vital importance because many

of the fabric properties, working of weaving machines and weaving preparatory

machines are dependent on yarn quality. The overall level of quality is increasing

constantly. Due to steadily growing production capacities, the quality consistency

must be improved.

Keeping this in mind, process control and yarn quality in spinning outlines the

concepts of raw material selection, control of various process parameters to

optimise the process conditions, and analysis and interpretation of various types of

test reports to find out the source of fault The parameters using in the ring frame process are given below:

The hardness of traveller should be less than the hardness of the ring surface. This practice

helps to optimise the life of ring surface. The traveller is cheaper than ring, so that maintenance

cost also gets reduced. The replacement method of traveller is more easy in comparison ring so

that reduced down time also helps to optimise the efficiency of the machine.

The hardness range 800 - 850 vickers of the ring surface gives the best results in term of life of

ring.

The weight of the traveller gets selected according to the spindle speed, yarn upon count, yarn

strength and material to be processed. Low traveller weight results in the form of low bobbin

density and and low cop content. The higher traveller weight causes high yarn tension. The

ends breakages get increased.

If the higher break draft is applied in the ring frame process, the draft setting gets more critical.

The break draft in the ring frame process is employed to the total draft in each case since the

main draft does not exceed 25 to 30.

The setting of front top roller is kept slightly forward by a distance of 2 to 4mm relative to the

front bottom roller, while the middle top roller is kept a short distance of 2mm behind the middle

bottom roller.

The overhang of the front top roller result in the form of smooth working of the top rollers and

reduces the spinning triangle. This helps to reduce the end breakage rate in the ring frame

process.

The back top rollers are coated with hard rubber generally because compact and twisted roving

enters to the back roller which does not need extra guidance and fibres control. The hardness

of rubber cots is kept 80 – 85 degree shore in the back front roller.

The hardness of rubber cots of front top roller ranges between 63 – 65 degree shore because

the drafted fibre strand contains very less number of fibres which needs extra guidance and

fibres control.

The proper setting in ring frame process has great importance. The specific shape of the cop is

achieved by placing the layers of yarn in a conical arrangement.

In the winding of a layer, when the ring rail gets moved upward direction, the rail traverse speed

is low at bottom and increased at top position.

When the rail comes downward direction, the rail's traverse speed gets maximum at top position

and minimum at bottom portion

This gives a ratio between the length of yarn in the main (up) and cross (down) windings about

2:1.

A maximum traveller speed of 40 m/sec can be achieved in modern ring and traveller

combination with good fibre lubrication.

The high contact pressure (up to 35 Newtons /square metre) gets generated between the ring

and the traveller during winding, mainly due to centrifugal force. This pressure leads to

generation of heat.

Traveller mass determines the magnitude of frictional forces between the traveller and the ring,

and these in turn determine the winding and balloon tension.

If a choice is available between two traveller weights, then the heavier is normally selected,

since it will give greater cop weight, smoother running of the traveller and better transfer of heat

out of traveller.

The total length of a complete layer (main and cross windings together) should not be greater

than 5m (preferably 4 m) to facilitate unwinding.

The traverse stroke of the ring rail is ideal when it is about 15 to 18% greater than the ring

diameter.

End break suction system has a variety of functions. It removes fibres delivered by the drafting

arrangement after an end break and thus prevents multiple end breaks on neighbouring

spindles. It enables better environmental control, since a large part of the return air-flow of the

air condition system is led past the drafting system, especially the region of the spinning

triangle.

In modern installations, approx. 40 to 50 % of the return air-flow passes back into the duct

system of the Air conditioning plant via the suction tubes of pneumatic suction system.

A significant pressure difference arises between the fan and the last spindle. This pressure

difference will be greater, the longer the machine and greater the volume of air to be

transported.

A relatively high vacuum must be generated to ensure suction of waste fibres for cotton -

around 800 Pascal for synthetic - around 1200 Pascal

The air flow rate is normally between 5 and 10 cubic meter per hour. Remember that the power

needed to generate an air-flow of 10 cubic meter/ hour , is about 4.5 times the power needed for

an air-flow of 6 cubic meter/ hour, because of the significantly higher vacuum level developed at

the fan.

5.2 Calculation of balancing of machines in different sections for a particular spin plan

requirement.

Spinning plan;-

RING-FRAME:

Count = 30

TPI = 21.02

speed = 15200

Effeciency = 95%

No. of spindle = 1008

No.ofm/c = 27

Spindle speed * 60 * 8 * Effeciency

Production = ___________________________________

TPI * 36 *840 * Count* 2.2

= 15200* 60* 8 * 0.95

21.02 * 36 *840* 30 * 2.2

= 165.215 gms/spindle/shift

Total production = 13489.4905 per day.

S/F Production required = 13489.4905/0.98

= 13764.786 per day.

SPEED-FRAME:-

Count= 0.78

TPI =1.24

Speed =1140

Efficiency=90%

NO. of spindle-=120

Production =Spindle speed *60*8*Efficiency

-----------------------------------------------------

TPI*36*840*count*2.205

= 1140*60*8*90

------------------------------------------

1.24*36*840*0.78*2.205*100

Production= 7.653 kg/spindle

918.436 kg/mc/shift.

No. of speed frame required = 13764.756/ 918.436*3

= 4.99

Draw-frame production required = 13764.786/0.98

= 14045.7 per day.

DRAW-FRAME:-

Delivery speed =462.6 mt. /min

TD =1.10

Efficiency =85%

Sliver Hank =0.1050

Production = Delivery speed*60*8*T.D*Efficiency

-----------------------------------------------------------

840*Sliver Hank*2.205

=462.6*60*8*1.10*85

-------------------------------------

840*0.1050*2.205*100

=1069.95 kg/shift.

No. of Draw-Frame required = 14045.7/1069.95*3 = 4.375

Comber production required = 14045.7/0.98

= 14332.346 per day .

COMBER:-

Nip/min =400

Feed/nip =5.1

Lap weight(gm/mtr) =78

No. of head =8

Efficiency =80%

T D =1.1

Noil % =18%

Production = nips/min.*Feed/nip*lap Wt. *No.of Heads*(100-W) /100*60*8*T.D*Effic.

------------------------------------------------------------------------------------------------------------

---

1000*1000

=400*5.1*78*8*(100-18) /100*60*8*1.10*80

---------------------------------------------------------------------

1000*1000*100

=440.912 kg/shift/m/c

No. of comber required = 14332.346/440.912*3

= 10.835

Unilap production required = 14332.346/0.98

= 14624.84

UNILAP:.

Delivery rate(m/min) =127

Lap weight(gm/mtr) = 78

Effeciency =80%

Production =Del.rate*Lap Wt. *60*8*Efficiency

---------------------------------------------------

1000*100

= 127*78*60*8*80

---------------------------

1000*100

=3803.904 kg/shift.

No. of unilap required = 14624.84/3803.904*3

= 1.281

Production required DIF = 14624.84/0.98

= 14923.306 per day.

Draw Frame

Delivery speed =822 mt. /min

T. D =1.10

Efficiency =80%

Sliver Hank =0.102

Production = Delivery speed *60*8*T.D*Efficiency

------------------------------------------------------

840* sliver hank* 2.205

=1842.016 kg/shift.

NO. of draw-frame required = 14923.306/1842.016*3

= 2.7005

Card production required = 14923.306/0.98

= 15227.863 per day.

CARD:-

Delivery rate 174 m/min

Sliver weight =5.02 K Tex

Effeciency =99%

Production = Delivery rate *Sliver wt. *60*8*Efficiency

---------------------------------------------------------------

1000

=174*5.02*60*8*99

-------------------------------

1000*100

=415.0776 kg/shift/m/c

NO. Of card required= 15227.863/415.077*3

= 12.228

B/R production required= 15227.863/0.98 kg

=15538.635 kg per day.