warp preparation for rope dyeing-1

Warp Preparation Requirements for Rope Dyeing

Ball Warping: Equipment required to form the rope of yarn. It involves creeling multiple ends of yarn ( Between 350-500 ends) and collecting them into an untwisted rope for dyeing. the rope is wound onto a long cylinder called a log on a machine called as a ball warper.

Some Notes

1. Packages of yarn are preconditioned before ball warping
2. Packages are loaded into the creel ( larger lots- magine transefer creeL0 and smaller lots- swing gate or truck creel
3. Packages are placed on adapters. An adapter support the package of yarn and ensure that the package remains aligned to the tensioning devices. Wooden plug type adapter are most effective as they require least amount of exertion to remove the empty package.

Next Step is threading the tensioner located at each yarn package

1. Post and Disk tensioner. It has two posts mounted onto a flat base. two round disk are placed onto each post. The yarn is threaded between the disk and wrapped around the post. One of the parts is movable so that the angle of wrap can be varied. More tension can be added to the yarn by adding round weights onto the top disk.

Advantages are 1. Inexpnsive 2. does Marginally adequate job of maintaining yarn tension 3. Simple to thread up 4. Low maintenance requirements.

Disadvantages are 1. Yarn has a tendency to jump out from between the disks at the rear of the creel. 2. It is labour intensive- when different tension levels are required. 3. There is more frequency of cleaning up 4. It doesnt control tension well at higher speed.

2. The driven disk tensioner

It also uses twin disk arrangement, however the disks are supported from below- there are no posts. Tension is applied from above- there are weights or spring loaded.
A gear under each pair of disks is matched to another gear mounted on a continuous shaft which runs the length of the vertical tension post. This shaft is connected to a 4 rpm motor which rotates the disk.

Advantage of disk rotation are 1. Thread cutting prevention 2. Dampens out variation due to ballooning action of yarn. There is mor uniform tension 4. Less effor required to change tension levels.

Disadvantages are 1. It is more difficult to thread up, there is more maintenance due to electric motor used and at high speed the tension control is not well.

loom shed

Process Control in Loom shed

It consists of two parts:
1. Increasing machine productivity
2. Improving quality or reducing defects

Control of the productivity can be done with

1. controlling nominal loom speed close to currently set standards.
2. Ensuring that loss of speed through belt slippage is minimum
3. Control of loss of loom efficiency by minimising:
a. Loom stoppage rate through correct maintenance
b. Control of down time of loom through corrective action on the basis of data collected by snap reading.

1.
2.

3. Factors effecting Loom efficiency

Various factors that affect the loom shed efficency are

1. Technical
2. Human ( Related to weaver skill and work methods)
3. Organisational

Relating the three factors

The technical and human (weaver related) factors have a very basic relationship with loom efficiency. The relationship is

P = NEX
= NE at

or E = P/ Nat
Where P= operative efficiency
N= number of machines per operative
E= Machine efficiency

X= Service factor, and it is equal to the average time taken to clear the stops in unit running time of a machine and equals at.
a= average no of stops per unit running time of a machine
t= average time to clear a stop including walking time

Thus if during an hour, the operator spends on an average 30 minutes in clearing stops, 15 min in ancillary durites like bringing raw materials etc and 15 min on rest and relaxation then
operative efficiency = (30 x 100)/60 = 50%
Work load = (30+15)x100/60 = 75%

Thus to maximise loom efficiency
- The stoppage rate should be low
- the weaver should be trained so that he takes the minimum possible time for clearing a stop.
- the operative efficiency should not fall below the optimum level
- loom allocation should be optimum

Costing in Drawing-in

Costing in Drawing-in

Drawers and reachers are paid their basic wages on piece rate system. The rates are related to the type of cloth to be woven. the basis of allocation of expenses to the different types of cloths are

1. Basic Wages of drawers and Reachers= Rate per 1000 ends x total production in 1000 ends.
2. DA to drawers and reachers and all other expenses = total production/production per shift

Cost of Drawing-in

Unit costs of this process as cost per 1000 ends. The cost of this process is calculated as shown below:

Cost of drawing-in per piece lengtrh = (cost per 1000 ends x total no of ends x tape length)/ weaver's beam length

Reed Calculations

Reed Calculations

In weaving, the reed is an important part of the loom. It helps to keep the warp ends evenly spaced and also helps in beating the weft into the fell of the cloth. Therefore, understanding reed count is essential for calculating the number of warp ends per inch in the fabric.

Reed calculations are often taught in a very short form, but a small mistake in terminology can create confusion. The reed count tells us about the number of dents, while the actual ends per inch depend on how many warp ends are passed through each dent. Similarly, heald calculations are related to the distribution of warp ends across shafts, not to the reed itself.

Table of Contents

• Stockport Reed System
• Particulars of Reed While Ordering
• Example 1: Finding Ends per Inch from Reed Count
• General Formula for Stockport Reed Count
• Plain Set and Heald Count
• Example 2: Heald Count for a 6-Shaft Satin Fabric
• Important Distinction Between Reed Count and Heald Count
• Summary
• Corrected Key Points
• General Disclaimer

Stockport Reed System

Reeds are commonly counted by the Stockport system. In this system, the reed count is based on the number of dents in two inches. This point is important. The Stockport system does not directly tell us the number of warp ends in two inches; it tells us the number of reed dents in two inches.

For example, a 72s Stockport reed means:

\[ 72 \text{ dents in 2 inches} \]

Therefore:

\[ \text{Dents per inch} = \frac{72}{2} = 36 \]

So, a 72s Stockport reed has 36 dents per inch. If one end is passed through each dent, the ends per inch will be 36. If two ends are passed through each dent, the ends per inch will be 72. If three ends are passed through each dent, the ends per inch will be 108.

Visual 1: Stockport reed count explained as dents in two inches and converted into dents per inch.

Particulars of Reed While Ordering

A reed may be specified as:

100s ST, 18 G., 44" × 5", blue

This means that the reed has a Stockport count of 100. Since Stockport count is based on two inches, this means that the reed has 100 dents in two inches, or 50 dents per inch.

• 100s ST: Stockport reed count is 100.
• 18 G.: The reed is made using dents of 18s wire gauge.
• 44": The reed is 44 inches long.
• 5": The reed is 5 inches deep.
• Blue: There will be blue paper on the baulk of the reed.

Here, “ST” refers to Stockport. The count tells us how many dents are present in two inches. The actual ends per inch will depend on the draft plan and the number of ends drawn through each dent.

Example 1: Finding Ends per Inch from Reed Count

Question: What will be the number of ends per inch at the reed in a reed of 3/80s Stockport?

Here, 80s Stockport means:

\[ 80 \text{ dents in 2 inches} \]

Therefore:

\[ \text{Dents per inch} = \frac{80}{2} = 40 \]

The expression 3/80s Stockport means that the reed is being drawn with 3 ends per dent.

Therefore:

\[ \text{Ends per inch} = 3 \times 40 = 120 \]

So, the reed will give:

\[ \boxed{120 \text{ ends per inch}} \]

This calculation is correct. However, it is technically clearer to say “ends per inch at the reed” rather than “ends per inch in the reed.” The reed contains dents; the warp sheet contains ends.

General Formula for Stockport Reed Count

For a Stockport reed:

\[ \text{Dents per inch} = \frac{\text{Stockport reed count}}{2} \]

If there are \(n\) ends per dent, then:

\[ \text{Ends per inch} = \frac{\text{Stockport reed count}}{2} \times n \]

Or:

\[ EPI = \frac{R \times n}{2} \]

Where:

• \(EPI\) = ends per inch
• \(R\) = Stockport reed count
• \(n\) = number of ends per dent

For example, if a reed is 72s Stockport and the drawing is 3 ends per dent:

\[ EPI = \frac{72 \times 3}{2} = 108 \]

Thus, the fabric will have 108 ends per inch at the reed, assuming no other change due to contraction, crimp, or finishing.

Visual 2: Formula flow showing Stockport count, dents per inch, ends per dent, and final ends per inch.

Plain Set and Heald Count

When a set contains 4 shafts, it is called a plain set. The count of healds is expressed by the number of heald eyes per inch across the complete set of shafts.

For example, a 60s plain set means:

\[ 60 \text{ heald eyes per inch across 4 shafts} \]

Therefore, the number of heald eyes per inch per shaft is:

\[ \frac{60}{4} = 15 \]

So, in a 60s plain set, each shaft has:

\[ 15 \text{ heald eyes per inch per shaft} \]

If the same total of 60 heald eyes per inch is distributed across 6 shafts, then:

\[ \frac{60}{6} = 10 \]

So, for a 6-shaft set, each shaft would have:

\[ 10 \text{ heald eyes per inch per shaft} \]

This distinction is useful because the reed controls spacing at the reed, while the healds control the lifting and lowering of warp ends according to the weave structure.

Example 2: Heald Count for a 6-Shaft Satin Fabric

Question: Find the count of healds required for weaving a 6-shaft satin fabric using a 72s Stockport reed, drawn 3 ends per dent.

First, calculate the dents per inch:

\[ \text{Dents per inch} = \frac{72}{2} = 36 \]

Since the reed is drawn 3 ends per dent:

\[ \text{Ends per inch} = 36 \times 3 = 108 \]

So:

\[ EPI = 108 \]

Now, the fabric is woven on 6 shafts. Therefore, the number of heald eyes required per inch per shaft is:

\[ \frac{108}{6} = 18 \]

So, each shaft must have:

\[ 18 \text{ heald eyes per inch} \]

To express this in terms of an equivalent plain set, remember that a plain set has 4 shafts. Therefore:

\[ \text{Plain set equivalent count} = 18 \times 4 = 72 \]

Thus, the required heald arrangement is:

\[ \boxed{18 \text{ heald eyes per inch per shaft on 6 shafts}} \]

Or, expressed as a plain-set equivalent:

\[ \boxed{72s \text{ plain-set equivalent heald count}} \]

Visual 3: Heald count calculation showing 108 EPI divided over 6 shafts and converted to plain-set equivalent.

Important Distinction Between Reed Count and Heald Count

A common confusion in weaving calculations is between reed count and heald count. The two are connected through warp density, but they are not the same thing.

A reed count tells us how many dents are present in a given length. In the Stockport system, this length is two inches. The reed controls the spacing of warp ends at the reed and helps beat the weft into the fabric.

A heald count tells us how many heald eyes are available per inch across the set of shafts. The healds control the lifting and lowering of warp ends according to the weave design.

Therefore, reed calculations are mainly concerned with:

\[ \text{Dents per inch and ends per dent} \]

Heald calculations are mainly concerned with:

\[ \text{Ends per inch and number of shafts} \]

Point of Comparison	Reed Count	Heald Count
What it refers to	Number of reed dents	Number of heald eyes
Main function	Spaces warp ends and beats the weft	Controls warp lifting according to weave design
Key calculation	Dents per inch × ends per dent	Total EPI divided by number of shafts
Common mistake	Calling dents “ends”	Confusing heald count with reed count

Related Reading on Weaving and Textile Calculations

• Textile Calculations: How to change the EPI and PPI when changing counts for a given fabric
• Warp and Weft Calculations: How to Make a Fabric Heavier Without Changing Its Character
• Calculations: Changing Cloth Weight and Weave Pattern While Keeping the Same Structure
• Textile Calculation: Finding the Length and Weight of Yarn in a Given Length of Cloth
• How to calculate the weight of Fabric

Summary

The Stockport reed system is based on the number of dents in two inches. To find dents per inch, divide the Stockport reed count by 2. To find ends per inch, multiply the dents per inch by the number of ends drawn through each dent.

For a 3/80s Stockport reed:

\[ \frac{80}{2} \times 3 = 120 \text{ ends per inch} \]

For a 6-shaft satin fabric using a 72s Stockport reed with 3 ends per dent:

\[ \frac{72}{2} \times 3 = 108 \text{ ends per inch} \]

Then:

\[ \frac{108}{6} = 18 \text{ heald eyes per inch per shaft} \]

And the plain-set equivalent heald count is:

\[ 18 \times 4 = 72 \]

So, the correct conclusion is:

\[ \boxed{\text{Required heald count = 72s plain-set equivalent}} \]

Or:

\[ \boxed{\text{6 shafts with 18 heald eyes per inch per shaft}} \]

General Disclaimer

This article is intended for educational understanding of basic weaving calculations. Actual production values may vary depending on loom type, yarn type, yarn tension, weave structure, crimp, reed space, drawing-in plan, fabric width, finishing shrinkage, and mill practice. The calculations shown here should be used as a technical starting point and should be verified through sampling before final production.