USE OF A FLUORESCENT COTTON DUST TRACER FOR AN ENGINEERING

ANALYSIS OF DUST EMISSIONS IN EARLY STAGES

OF COTTON TEXTILE MANUFACTURING

by

LAWRENCE GILBERT DANIEL, B.S., B.A.

A THESIS

IN

CHEMICAL ENGINEERING

Submitted to the Graduate Faculty of Texas Tech University in

Partial Fulfillment of the Requirements for

the Degree of

MASTER OF SCIENCE

IN

CHEMICAL ENGINEERING

Approved

Accepted

May 1981

ACKNOWLEDGMENTS

This thesis is dedicated to the memory of Professor Jack D. Towery

who contributed significantly to my understanding of cotton textile pro­

cessing.

Major credit for this research effort is ascribed to my trusted

counselor and guide. Dr. Robert M. Bethea, whose direction and advice is

sincerely appreciated. I am deeply grateful to Drs. Philip R. Morey and

Steven R. Beck for their generous help and for the many improvements due

to their suggestions. I also wish, to express my appreciation tc Mr.

Edwin R. Foster and the Textile Research Center at Texas Tech University

for their invaluable aid in process research. I acknowledge with grati­

tude the Natural Fibers and Food Protein Commission of Texas for provid­

ing the Zeiss Photomicroscope III which played a vital role in this re­

search. A special thanks is extended to Mark Drosche for his superb

drawings and to Sue Willis who typed the manuscript with great care and

patience.

Finally my fondest thanks go to my wife Gay; she cheerfully proof­

read the manuscript and its many revisions. I was always blessed with

her support and encouragement.

n

TABLE OF CONTENTS

PAGE

ACKNOWLEDGMENTS ii

LIST OF TABLES v

LIST OF FIGURES vi

CHAPTER I INTRODUCTION 1

CHAPTER II LITERATURE REVIEW 3

CHAPTER III METHODOLOGY 9

Determination of Label in Airborne Dust 9

Sieving of Macro Samples 10

Determination of Label in Macro Samples 11

CHAPTER IV ENGINEERING ANALYSIS !4

Problem Definition 14 Engineering Studies 14

Description of the Process 16

CHAPTER V RESULTS AND DISCUSSION 31

CHAPTER VI CONCLUSIONS AND RECOMMENDATIONS 42

REFERENCES 43

APPENDIX 46

CALCULATIONS 47

Feeders and Feed Hoppers 47

Roller 47

Superior Cleaner 48

Impact Cleaner 49

CMG* Cleaner 50

Blade Beater 51

Kirshner Beater 55

Calender Rolls 59

m

TABLE OF CONTENTS

PAGE

ACKNOWLEDGMENTS ii

LIST OF TABLES v

LIST OF FIGURES vi

CHAPTER I INTRODUCTION 1

CHAPTER II LITERATURE REVIEW 3

CHAPTER III METHODOLOGY 9

Determination of Label in Airborne Dust 9

Sieving of Macro Samples 10

Determination of Label in Macro Samples 1!

CHAPTER IV ENGINEERING ANALYSIS 14

Problem Definition 14 Engineering Studies 14

Description of the Process 16

CHAPTER V RESULTS AND DISCUSSION 31

CHAPTER VI CONCLUSIONS AND RECOMMENDATIONS 42

REFERENCES 43

APPENDIX 46

CALCULATIONS 47

Feeders and Feed Hoppers 47

Roller 47

Superior Cleaner 48

Impact Cleaner 49

CMG^ Cleaner 50

Blade Beater 51

Kirshner Beater 55

Calender Rolls 59

m

PAGE

L icker - in 63

Flats and Main Cylinder 63

Doffer and Main Cylinder 65

S l iver 65

TV

LIST OF TABLES

PAGE

Table 1. Forces Exerted and Percentage of Labeled Particles by Size Class in Opening and Cleaning 33

Table 2. Forces Exerted and Percentage of Labeled Particles by Size Class in Picking 34

Table 3. Percentage of Labeled Particles in Respirable Airborne Dust 36

Table 4. Percentage of Labeled Particles in Total Airborne Dust 39

Table 5. Forces Exerted and Percentage of Labeled Particles by Size Class in Carding 40

LIST OF. FIGURES

PAGE

Figure 1. Feeder Section 17

Figure 2. Superior Cleaner 19

Figure 3. Impact Cleaner 20

Figure 4. CMG'^ Cleaner 22

Figure 5. Feed Hopper 23

Figure 6. Blade Beater 25

Figure 7. Kirshner Beater 27

Figure 8. Calender Roll Section 28

Figure 9. Carding 29

Figure 10. Process Flow Sheet 32

VI

CHAPTER I

INTRODUCTION

Cotton dust is defined as "dust present during the handling or pro­

cessing of cotton which may contain a mixture of substances including

ground-up plant matter, fiber, bacteria, fungi, soil, pesticides, non-

cotton plant matter and other contaminants which may have accumulated

during the growing, harvesting and subsequent processing or storage

periods" (28). The action of this dust on the human respiratory pas­

sages results in the development of byssinosis. The permissible expo­

sure limit for cotton dust in textile manufacturing is 0.20 milligram '^

of lint-free, respirable dust per cubic meter of air sampled by the

vertical elutriator.

Although the specific causative agents have not been identified,

toxicological evidence points to the bract of the cotton plant as the

source of the bioactive material (4). In order to verify that bract

and leaf-like materials are major ingredients in respirable cotton dust,

a technique for tracing plant part friability into the respirable range

was needed. It was proposed (17) that fluorescent labeling techniques

be developed for following the breakup of botanical trash components

into respirable cotton dust. The evaluation of that technique in cot­

ton ginning (2) and carding (2) has demonstrated the feasibility of

tracing labeled botanical constituents through those cotton processing

operations.

The objective of this research is the evaluation of the feasibi­

lity of tracing labeled botanical constituents through the early stages

1

of cotton textile manufacturing. For this purpose, raw cotton produced

as a result of ginning bulk seed cotton incorporating 0.1 weight per­

cent cotton leaves labeled with color index basic yellow 37 (BY 37) dye

in the course of previous research (2) was processed through the Textile

Research Center at Texas Tech University. If labeled material, added

to bulk seed cotton before ginning, can be accurately traced through

ginning, opening, cleaning, picking and carding, then this will have

demonstrated the ability to trace labeled botanical constituents through

succeedingly finer micronizations (10). The successful conclusion of

this research will provide a basis for ascertaining the extent of the

presence of leaf-like botanical components, such as bract, in the res­

pirable range and thus aid in an engineering analysis of cotton dust

emissions in opening, cleaning, picking, and carding. Separation of the

cotton dust into discrete particle size fractions was accomplished

using a set of U.S. standard testing sieves. Epifluorescence micro­

scopy was employed to follow the dispersion of labeled material into

the trash and product streams and monitor airborne particulate matter.

CHAPTER II

LITERATURE REVIEW

The harmful effects of hemp, flax and cotton dust have been observ­

ed since the early eighteenth century in French and English textile mills

Evidence that these harmful effects were associated with a progressive

respiratory disease eventually led to English recognition of byssinosis

as a compensable illness (25). McKerrow and Schilling found evidence

in 1960, that byssinosis also existed in the cotton industry in the

United States (14). In 1976, it was estimated by George Perkel that the

prevalence of byssinosis in yarn preparation departments of the U.S.

cotton textile industry effected 20 to 30 percent of the work force (26).

The diagnostic identification of byssinosis is based upon subjec­

tive complaints of chest tightness and cough, alone or in cor.::jination

with dyspnea. These symptoms occur most severely upon return to work

after some absence (hence the term "Monday fever syndrome") with sub­

sequent reduction in symptoms on repeated exposures (8).

These complaints are frequently accompanied by a decrease in the

forced vita! capacity as measured by FEV,, the forced expiratory volume

in one second. It is believed that these observed symptoms are attri­

butable to the action of the dust on the mucous membranes of the respira­

tory passages (13).

Although neither the mechanism of action of the dust nor the speci­

fic causative agent(s) are known, certain hypotheses have been ad­

vanced in an attempt to determine the pathogenesis of byssinosis.

Rylander and Snella attributed the disease to a microbial component,

3

most probably endotoxins. They found that endotoxins, which are a com­

ponent of the cell wall of gram-negative bacteria, v/ere responsible for

eliciting a reaction pattern which was similar to that obtained after

exposure to water extracts of micronized bract samples (24). Fischer,

et al. determined that bracts are the source of large numbers of gram-

negative bacteria (7). Bouhuys and co-workers ascribed byssinosis to

cotton dust histamine-!iberating action. They found that the inhalation

of an aerosolized aqueous extract from bracts contained chemical agents

that would release histamine and produce acute symptoms of byssinosis

(4).

While no study has yielded definitive results concerning the path­

ogenesis of byssinosis, all implicate cotton bract as a major source of

cotton dust. As convincing as the evidence appears, it may be mislead­

ing because of the noticeable lack of control studies on other cotton

plant parts. Apparently bract is preferentially tested because the

evidence presented by Bouhuys and his collaborators, that the bract of

the cotton plant contains an active material causing byssinosis, is

presumed impressive (13). Nevertheless, it has been established that

the prevalence of byssinosis is related to the concentration of lint-

free respirable cotton dust. This dust is composed of particles 15 um

or less aerodynamic equivalent diameter as measured by a vertical elutri­

ator or equivalent method (12, 15).

As bract is a major component of botanical trash (6, 17) which in

turn is believed to be micronized into cotton dust during the process­

ing of cotton (19), it has been suggested that cotton bract is the likely

carrier of most of the causative agent(s) responsible for byssinosis '13).

In order to verify this supposition, evidence must be presented to

show that bract is indeed micronized into respirable cotton dust during

cotton processing at the textile mill. Unfortunately, bract is not the

only component of botanical trash. Morey and Bethea (17) showed that

leaf material is also present in major proportions in size classes less

than 420 ym in diameter. They also found that bract and leaf are

morphologically indistinguishable in the respirable range and suggested

that fluorescent tracer techniques be used to determine the botanical

origin of particles present in respirable cotton dust (17). Rowlett

was able to show that leaf material, its friability uneffected by dyeing,

was micronized into respirable cotton dust during pilot-scale ginning

by developing techniques to fluorescently label cotton leaves, mix them

in controlled proportions into raw seed cotton, take representative

airborne and spot samples during ginning and evaluate the amount of

labeled material present in those samples (2).

The Occupational Safety and Health Administration (OSHA) has pro-

mu'

lint-free respirable cotton dust for textile manufacturing. At the

time of this writing, the proposed standard for occupational exposure

to cotton dust has been upheld by the U.S. Court of Appeals and is cur­

rently under review by the U.S. Supreme Court. Until the causative

agent(s) is identified permitting specific action to be taken, compli­

ance will necessitate the development of adequate engineering controls

to reduce cotton dust levels in the working environment. The economic

burden of compliance will be severe. OSHA estimated, in 1978, that

ilgated a standard of 0.2 mg/m permissable exposure limit (PEL) of

the compliance cost for the entire cotton processing industry would be

$656 million in capital and $206 million annually (28). Industry esti­

mates are higher (26).

In order to be successful, engineering controls must permit the

capture of cotton dust at the source of generation and the removal of

cotton dust from the air before it is recycled. Recycling conditioned

air is necessary industrial practice in American textile mills for humi­

dity and temperature control (11). The principles of engineering anal­

ysis (1) lend themselves readily to the preparation of recommended tecn-

nical guidelines for control technology implementation. This involves

technological and economic considerations as to selecting and designing

devices which will meet the control requirements at the lowest annual­

ized cost but with maximum reliability expressed over the operating

life of the equipment.

Since it is believed that cotton dust consists largely of the micro­

nized portions of botanical trash initially incorporated into the bulk

seed cotton during harvesting (19), then the total trash (or non-lint)

content of the cotton being processed must be of concern to any analysis

of the problem. The amount, distribution and type of botanical trash

depends on the harvesting method, ginning method, variety growing sea­

son, soil type, geographic location and cultural practices acting on

plant growth (5, 18, 22). It is reasonable to expect that cotton dusts

in textile manufacturing mills using different sources of baled cotton

will contain different concentrations of trash and thus different con­

centrations of the causative agent(s) (21). Therefore the cleaner the

cotton reaching the mill, the greater the chance of reducing dust

concentrations below the hazardous level. Indeed, it has been shown

that steaming a continuous bat of cotton after ginning decreases the

concentration of airborne dust while carding; however this may result

in increased dust levels in spinning (27). This approach to dust pre­

vention has also been applied to genetic research (31) and to ginning

(29, 30). Ginning research has shown that the weight percent bract in­

creases with decreasing trash particle size (18) and that successive

numbers of lint cleanings generate smaller particle sizes (23). The

visible Shirley trash content in baled cotton varies from less than

1 percent to more than 8 percent with a mean value of 1.6 percent (9)

and steadily decreases as the cotton is processed.

Unfortunately, little is known about the trash levels in each

stage of cotton textile manufacturing. This information, especially as

it relates to respirable dust composition and concentration, would be

an important adjunct to the engineering analysis of cotton dust emis­

sions in textile mills.

It has been strongly suggested that hazard at the workplace would

be most accurately measured by concentration of causative agent(s) in

the dust rather than by mass concentration of the dust (3). This is

supported by findings that high concentrations of dust are associated

with a low prevalence of byssinosis in certain non-textile segments of

the cotton industry where raw materials have a low content of leaflike

trash (16).

Bract is thought to be the probable carrier of most of the causa­

tive agent(s) responsible for byssinosis (13) and is botanically similar

to dyed cotton leaves added to bulk seed cotton prior to ginning (2).

8

Therefore it should be possible to more accurately predict the byssino-

tic risk, based on the probable carrier of most of the causative

agent(s), by following the micronization of dyed leaf material into

respirable cotton dust during opening, cleaning, picking and carding.

The amount of labeled particulate matter in airborne and spot samples

can be determined using epifluorescence microscopy (2, 20). In turn

this should lead to an improved engineering analysis of dust emissions

in the early stages of cotton textile manufacturing.

CHAPTER III

METHODOLOGY

The fol lowing procedure allows the determination of the percentage

of labeled part ic les in each sample by comparing BY 37-dyed part ic les

to non-dyed par t ic les. This is made possible by thei r difference in

fluorescence. BY 37-dyed part ic les emit a yery bright yellow f luore-

sence when viewed under u l t rav io le t l i gh t whereas the undyed part icles

do not.

Determination of Label in Airborne Dust

Determining the amount of labeled part iculate in airborne samples

is accomplished by using a Zeiss Photomicroscope I I I equipped with both

white l i g h t and long-wave u l t rav io le t i l lumination systems. Vertical

e l u t r i a to r f i l t e r s are placed dust side up on a clean glass sl ide and

a No. 1-1/2 covers!ip is placed on top of the f i l t e r . A 50 gram lead

weight is placed on top of the covers!ip for 30 to 60 seconds and then

removed. With the aid of tweezers, the covers!ip with adherent dust

part ic les on i t s lower surface is transfered to a second clean glass

s l ide for epifluorescence microscopic examination. This procedure is

repeated twice more giving three subsamples per f i l t e r . Total p a r t i ­

culate (high volume) f i l t e r s are placed dust side up and three No. 1-1/2

covers!ips placed on top of d i f fe ren t , randomly selected areas of the

f i l t e r . The three subsamples are prepared as before. Particles of dust

trapped between the glass sl ide and covers!ip are exposed to ref lected

long-wave u l t rav io le t l i gh t (334 and 365 nm peaks) and fluorescent

10

observations of BY 37-dyed vs. nondyed part ic les are made using a numer­

ical aperture 0.75 Zeiss neofluar 40X object ive. F i f ty random f ie lds

are viewed on each subsample. Fields that do not contain BY 37-dyed

part ic les are not counted. The counting procedure for f ie lds contain­

ing one or more BY 37-dyed part ic les is as fol lows. Because of the large

number of part ic les per f i e l d , a diameter of the c i rcular f i e l d is ex­

tended through each BY 37-dyed part ic le present and the tota l number of

part ic les along each diameter is counted. After a l l f i f t y f ie lds have

been viewed, the ra t io of the sum of a l l labeled part ic les observed to

the sum of a l l part ic les along diameters is recorded. This ra t io is

then mul t ip l ied by the f ract ion of f ie lds containing BY 37-dyed pa r t i ­

cles to obtain an estimate of the re lat ive amount of labeled part iculate

per subsample. This value is then converted to a pe r - f i l t e r basis.

Sieving of Macro Samples

Part ic le size separations of macro samples are accomplished by the D

use of a Tyler standard sieve series and a Ro-Tap shaker. The series

consists of 10, 14, 20, 40, 60 and 100 mesh sieves corresponding to

1.651, 1.168, 0.833, 0.420, 0.246 and 0.147 mm square openings, respec­

t i ve l y . The sieves are arranged in order of decreasing part ic le size.

A catch pan is included under the 100 mesh sieve. Each sample is de­

posited on top of the clean 10 mesh sieve. The mass of f iber is care­

f u l l y pulled apart for three minutes to dislodge entangled trash mate­

r i a l . The l i d is then placed on top of the 10 mesh sieve and the stack

of sieves placed on the Ro-Tap shaker for three minutes. This proce­

dure is repeated twice more to give a tota l of three shakings. The

11

contents from the surface of each sieve and the catch pan are then

placed in sample containers. The series of sieves is thoroughly clean­

ed by tapping with a soft bristled brush between samples. Each sample

is separated into the sizes shown below:

U.S. Standard Sieves mm

+10 X > 1.651

10/14 1.168 < X ± 1.651

14/20 0.833 < X < 1.168

20/40 0.420 < X £ 0.833

40/60 0.246 < X £ 0.420

60/100 0.147 < X £ 0.246

-100 X < 0.147

The +10 size fraction is that sample retained on the 10 mesh sieve; the

-100 size fraction is that portion of the sample which passed the 100

mesh sieve and is caught in the pan.

Determination of Label in Macro Samples

Because no single viewing method is applicable to the entire size

range of macro samples, it is necessary to divide the size range in

order to accommodate the most efficient viewing method. Particles in

the +10, 10/14 and 14/20 size fractions are viewed against a black back-p

ground under a Blak-ray model B-IOOA mercury vapor, lOOW, long-wave

ultraviolet light source fitted with a Kodak Wratten #18A exciter fil­

ter. This ultraviolet source is positioned approximately 20 cm from

the sample to be viewed and illuminates from the side. All extraneous

12

light is eliminated and a visual count made of BY 37-dyed particles;

then all the particles are viewed and counted under incandescent light.

Subsamples are prepared for viewing depending on the number of particles

and amount of lint present. Samples containing less than 300 particles

are viewed in toto. Samples which contain larger numbers of particles

are quartered and opposite-diagonal quarters retained. These two quar­

ters are in turn combined and quartered again. This time the other

pair of opposite-diagonal quarters are retained. This continues until

approximately 100 particles remain. The procedure is repeated twice

more to give a total of three subsamples for viewing. Samples which

contain a large amount of lint are spread out on a black background and

a 5.7 X 11.4 cm (2-1/4 x 4-1/2 in.) field layed out at random to provide

a grid for viewing. All particles within this area are viewed. This

procedure is repeated twice more in different, randomly selected areas

of the sample to give a total of three subsamples.

Particles in the 20/40, 40/60, 60/100 and -100 size fractions are

viewed under appropriate magnification, utilizing the same Zeiss Photo­

microscope employed in the evaluation of airborne dust samples. Sub-

samples are prepared for viewing in the following manner: if the sample

consists of less than 300 particles, all particles are viewed. If the

sample consists of a larger number of particles, the quartering proce­

dure mentioned previously is employed. Samples which contain only lint,

are scanned to determine whether or not trash particles are agglomerated

on the fibers. In addition, lint fibers from every sample are routinely

scanned for the same purpose. All subsamples are placed on a clean

glass slide and a No. 1-1/2 clean glass coverslip placed on top. The

13

subsamples are exposed to ref lected long-wave u l t rav io le t l i gh t and ob­

servations made using a numerical aperture 0.20 Zeiss neofluar 6.3X

object ive. Part ic le counts are made by viewing f i f t y random f i e lds .

The number of BY 37-dyed part ic les re lat ive to the tota l number of

part ic les in a f i e l d is recorded, and this ra t io is mult ip l ied by the

f ract ion of a l l f ie lds containing BY 37-dyed par t ic les. This value is

then converted to a p e r - f i l t e r basis in order to obtain an estimate of

the re la t ive amount of labeled part iculate matter per sample.

CHAPTER IV

ENGINEERING ANALYSIS

The techniques of engineering analysis can provide valuable infor­

mation in the definition of needed control technology for cotton textile

manufacturing. This engineering analysis is directed toward defining

the problem of fugitive cotton dust emissions in the early stages of

cotton textile manufacturing in terms of relative severity rather than

total dust emissions. This analysis also includes engineering studies

undertaken to determine the characteristics of each emission source.

Problem Definition

An estimation of the relative severity of cotton dust emissions in

the early stages of textile manufacturing can be made by determining

the percentage of labeled particles in airborne samples. Since these

estimates are based on the probability of finding labeled particles

in random samples, the nature of the data and results are relative

rather than absolute.

Engineering Studies

If labeled plant material is broken up by processing machinery,

then it should be possible to identify the sources of harmful emissions

by following the micronization of such material through opening, clean­

ing, picking and carding into the respirable range. Toward this end,

the forces exerted on the cotton during each process step have been

evaluated qualitatively as to type and a relative force (F) calculated.

The classification of each force is based upon its primary application.

14

15

In this respect compression, impact and tensile forces correspond to

the respective applications of compressing, beating or pulling the cot­

ton bat. Force calculations are based on the following equations:

w = fx (1)

f = ma/gc (2)

Ep = ngh/gc (3)

E, = 1/2 mv^/gc (4)

m = pV (5)

V = cor (6)

where a = acceleration (ft/s )

E, = kinetic work (ft Ib^)

E = potential work (ft Ib^)

f = force (Ib^)

g = acceleration due to gravity (ft/s ) 2

gc = conversion factor (32.2 Ib^ ft/lb^ s )

h = height (ft)

m = mass (lb„) m

r = radial arm (ft)

V = volume (ft )

V = linear velocity (ft/s) X = distance (ft) p = density (Ib^/^t^)

oj = angular veloci ty (rad/s)

The calculated force represents a re lat ive estimation of the work

done on the labeled part ic les in specif ic stages of manufacturing.

16

Apparently, much of the applied force is absorbed by the cotton bat

rather than the particles. Because of this, the force applied per area

of particle cannot be calculated. In addition, the masses and sizes of

the machinery have been used to estimate the forces exerted by the equip­

ment. For these reasons, relative rather than quantitative estimates of

energy expenditure were used in the engineering analysis calculations.

Description of the Process

Opening, cleaning and picking consist of several steps to transform

a tightly formed bale of raw cotton, trash and other foreign material

into a lap or a rolled sheet of partially cleaned cotton ready for card­

ing. These steps include such operations as blending, feeding, reduc­

tion in particle size, waste remove!, material handling, evening, lap

formation and packaging.

The opening section of the Textile Research Center consists of four

feeders, as shown in Figure 1, each designed to receive the layers of

raw cotton by hand. The cotton is deposited on a slowly moving feed

apron (A) and carried to a faster moving inclined apron (B) which is

equipped with spikes to lift and carry the cotton up to the weigh pan

(C). As the cotton is carried up the inclined apron, the flow is regu­

lated by the comb (D) which pulls the excess cotton back into the hopper

space. The cotton which is brushed off by the brush roller (E) into

the weigh pan is automatically weighed and dropped on a conveyor belt

(F). The forces applied in the feeders are predominantly tensile forces

used for opening and blending the large hand-fed masses of cotton.

17

e o L.

a. < •o aj 0)

u.

c o ^ & <

• 3

<u c *» r > ^

u ^

e « a. £ O l

•.— u 2

n O

<_>

u w ^ f > ^

o OE

f l/l

a L. I S

e o u a. < L.

o > 01

> c o (_>

u 00

s -

OJ (1)

< 31 O

18

Before the cotton is fed into the Superior Cleaner, Figure 2, a

small compression force under a fifty pound roller (A) is applied.

This facilitates feeding into the Superior Cleaner. The Superior Cleaner

opens the cotton by a series of six horizontal beaters (B) arranged at

an angle of 60° upward. The entering cotton is picked up by the first

and lowest beater and progressively raised and beaten by each of the

succeeding beaters until it reaches the top. Each beater is fabricated

around a cylindrical drum fitted with metal studs mounted spirally

around the surface. Beneath each beater is a series of grid bars (C).

Opening is accomplished by the action of the beaters raking the cotton

over the grid bars. Impact forces are exerted on the cotton in this

process. Cleaning is accomplished as the heavier particles pass over

and fall through the grid bars into the collection bin (D).

From the Superior Cleaner, the cotton bat is pneumatically conveyed

to the impact cleaner. Figure 3. By using a fan to blow the cotton from

the Superior Cleaner to the impact cleaner, handling is reduced to a

minimum. At the inlet duct (A) to the impact cleaner, the cotton is col­

lected on a revolving condenser screen (B). The air containing dust,

short fibers and trash passes through the perforated screen and into a

vacuum bag filter where the larger suspended particles are captured.

The cotton is removed from the screen by a doffer roll (C) and dropped

into the impact cleaner. The impact cleaner consists of seven spiked

beaters (D), similar to those in the Superior Cleaner, and seven grind­

ers (E) covered with 0.5 inch long ceramic teeth. In the impact cleaner,

the cotton is further opened and cleaned by the action of the beaters

and grinders arranged at an angle of 60° upward. After being picked up

19

e ui O V . • > -

{/> la -ij

I. u ca u .— <-> - a >— o <u u o oe a c9 u

(U

c

o

o s_ Q_

O) s -3 cn

20

c rtJ <u

+J a a .

<r>

cn

' • ! ' •

4 J

u 3 O

C 9>

t U I / )

u OJ W)

c 91 • o c o o

JZ o ae u 01

>.-<4-

8

tfi

u a; 4.) 19 V

CO

</> u 0) • o c I . o

c I S

c o

*J

u 01 p ^ ^m

o <->

< CD U O

21

by the first beater, the cotton is ground, beaten and raised by succeed­

ing beaters and grinders until it reaches the top of the impact cleaner.

The action of beating and grinding the cotton is due primarily to im­

pact forces. The heavier particles liberated during the process fall

out of the cotton bat, due to gravity, and into the collection bin (F)

in the bottom of the impact cleaner.

Following the impact cleaner, the cotton is dropped into the CMG'^

cleaner. Figure 4, where it is picked up on the licker-in cylinder (A).

The licker-in cylinder is covered with short metallic wire and acts by

tearing away tufts of cotton and carrying them to the worker cylinder

(B). The worker cylinder revolves at a higher rate than the licker-in

so that complete fiber transfer from licker-in to worker is affected

by a stripping action. The cotton is then combed onto the stripper

cylinder (C) and subsequently transfered back to the lick:r-in by the

same stripping action as before. The forces involved in these opera­

tions are basically tensile in nature since the cleaning action is ac­

complished by pulling fibers apart and allowing entrained particulate

matter to fall out. Once the cotton is transfered back to the licker-

in, impact forces are exerted in raking the cotton across a short sec­

tion of grid bars (D) freeing the heavier material to fall out into

the collection bin (E). Lastly the cotton is brushed off the licker-in

by the brush roll (F) and discharged into a duct (G).

The cotton is now pneumatically conveyed to the feed hopper,

Figure 5, where it is collected on a revolving condenser screen (A).

Suspended particulate matter passes through the perforated screen and

into a second bag filter. The cotton is removed from the screen by a

22

Qi

e3

a;

C7i

^ V •o e ••" > i u c - 1 I .

a> j ^

(J T ^

—i

I .

•s c * -^ M

>* u u OJ

^ b.

o 2

u 4J

•a c

.•— > 1

u s-01

o. a. • » "

u 4 J WO

(/> i . "O

0 9

• o

u o

C

oa c o •••" 4-1

u 0 )

^^ l—m

o KJ

p ^

^ M

o ae

.^ <A 3 S.

S

*J (J 3

O

<C a u o Lu u. c9

23

O

• o

m QJ

24

doffer roll (B) and dropped onto the feed apron (C). The primary func­

tion of the feed hopper is to regulate the flow of cotton to the blade

beater. Cotton is lifted by a spiked inclined apron (D) and carried

up to the comb (E) which exerts tensile force to pull excess cotton back

into the feed hopper. The cotton passing over the top of the feed hop­

per is brushed off by a brush roll (F) and onto a short horizontal

apron leading to the blade beater. This represents the first step in

picking, where the cotton is formed into an even, flat sheet to be roll­

ed into a lap. In addition, final cleaning is performed.

At the blade beater. Figure 6, the cotton is gripped by a pair of

spring-loaded feed rollers (A) while the two-bladed beater (B) strikes

the cotton and drags it across the grid bars (C) to the double conden­

ser screens (D) where the cotton is again formed into a flat sheet.

Trash particles and some short fibers fall out between the grid bars

into the waste as a result of impact forces exerted by the blade beater.

The fan (E) draws room air through the perforations in the top and bot­

tom condenser screens and through the beater box (F). This air, con­

taining entrained dust and cotton, passes down the dust flue and out of

the fan discharge (G) through the duct (H) and into the filter housing

(J). Then it passes through a perforated filter screen (K) and is re­

circulated. This filter uses a mat of fibers as the filter medium.

The mat is continually stripped off and deposited into a waste recep­

tacle as the filter screen revolves. The particulate matter removed

from the cotton on the double condenser screens, which is too large to

remain suspended in the air stream falls out and is collected under the

double condenser screens.

25

<u 4-) fO OJ

oa

nj

ca

O)

cn

u> t . (U

r - M

O Q:

• o

« 01

u OJ J ^

I Q V

oc <u

• o •a

^w s a

i/i 1 .

« CO

•o * " I . 4 3

« £ u

wn U u l/»

c 01

• a e o

. u u

« • •

^ 3

,s c « u.

X o

a I . o> *rf •a OJ

oa

OJ o> L. fl

f u 1/1

- » a c (o

L ^

.>J

u 3

O

o> d

• f—

v> 3 O

. !. OJ

. A ^

— - u.

c V 0)

u u l

L. 01 4-i

( .— u.

< ( a o a ' . ^ ^ ( a ~ ~ 3 ^

26

The cotton passes from the blade beater to the Kirshner beater.

Figure 7. Here the cotton is deposited into a blending reserve (A).

The purpose of the blending reserve is to maintain a uniform flow of

cotton to the Kirshner beater (B) where the final picker cleaning takes

place. The Kirshner beater is a three-leg steel beater fitted with

small spikes on the base of each leg. As the cotton is fed to and held

by the evener roller pedal (C), the Kirshner beater strikes the cotton

downward and across the grid bars (D) dislodging much of the remaining

trash which falls out through the grid bars. The forces exerted by the

Kirshner beater in striking the cotton are predominantly impact in

nature. The cotton is thrown up onto the double condenser screens (E)

and reformed into the final sheet. As in the blade beater section,

the Kirshner section fan (F) draws room air through the double conden­

ser screens, picking up small trash particles and short fibers. The

dirty air stream is routed through the duct (G) to a perforated filter

screen (H). The cleaned air is then recirculated. Larger trash parti­

cles fall out of the air stream and into the waste under the double con­

denser screens. The final compression of the loose sheet of cotton into

the picker lap occurs in the calender roll section. Figure 8. The sheet

of cotton is subjected to compression forces to bind the bunches of

cotton together so that they remain in sheet form for rolling. This

is accomplished by a stack of four calender rolls (A) one above the

other. Next, the lap is fed to the lap arbor (B) where it is rolled

into the picker lap for carding.

The process of cotton spinning actually begins in carding. Fig­

ure 9. The purpose of carding is to separate the fibers into their

27

s -

cn

sz sz in

OJ

cn

<u > s-01 1/) 1) ex w e

• ^

-o c 01

3 3

L. 01 • J "O 01

CO

u «J c ^ 1/1 u •*" ^

f ^

19 "O 01 a . L. 01

< o OE

U 01

0>

> LU

VI 1 . <a ca

^ •t—

i . o

ot 0> i-u

</ l

I . OJ lA

^ OJ • o c o

< J

OJ f-^

.a Z3

<s »• <e

u .

4-i <J 3

O

c OJ OJ I . t j

1/1

k. OJ * J

^ • »

-^

28

o a;

o ex: s-

-o Qi

«3

CO

s-

cn

o

o (U

c < 0)

— Q .

C_3 - J

< oa

29

s_ OJ T3 </l

3 . 01 = OJ •a '— *J C — >

_ i — . m •— •— •<-O — I >. c

i~ a o. u <_) ^ OJ OJ */1

J< 'O ~ - ^ C 01 <^ <J OJ OJ <J ••" *J •« — OJ « — « a — Q. u. u. _i £ £ ^

cn

OJ

cn

-^ * " •

o C£

1 . OJ <*. «fc-

c o

^ s o <-> u OJ

I w • b

<s

c OJ

1—

>e o I . OJ <.-u-8

I . OJ

.fm

o

'—' a uj u. : i ^ ^

30

individual elements and align them in parallel fashion. During carding,

most of the remaining dust and foreign matter as well as many short

fibers are removed. The picker lap (A) is fed beneath a feed roll (B),

resting against the feed plate (C), which regulates the flow of cotton

being worked on by the licker-in (D). The licker-in is a hollow cylin­

der covered with metallic wire. It acts to open the cotton lap by tear­

ing away tufts of fiber (tensile forces exerted) and carrying them to

the main cylinder (E). Mote knives (F) are set below the licker-in and

serve to catch and pull out foreign matter. The main cylinder, covered

with fine wire clothing, revolves faster than the licker-in, permitting

complete fiber transfer through a stripping action involving tensile

forces. The cotton fibers are carried up to the flats (G) where card­

ing occurs. The flats consist of approximately one hundred and ten

narrow flat surfaces covered with fine wire clothing to match the main

cylinder. The flats move slowly in the same direction as the main

cylinder. The wire points on the flats are inclined backwards or op­

posite to the direction of the wire points on the main cylinder. The

action between the two sets of points permits the fine separation of

fibers through the application of tensile forces. The transfer of

cotton fiber from the main cylinder to the slower doffer roll (H) is

also due to carding action. Following this, the thin film of cotton is

stripped from the doffer roll as a web by the action of the doffer comb

(J) and the wide sheet of card web is then drawn and gathered into a

round sliver by the action of the two doffer calender rolls (K). Last­

ly, the sliver is fed to the coiler (L).

CHAPTER V

RESULTS AND DISCUSSION

The flow scheme covering the early stages of textile manufacturing

in the Textile Research Center is shown in Figure 10. All sampling

points are indicated.

Tables 1 and 2 show the relative forces exerted on the cotton at

specific locations in opening and cleaning and picking, respectively.

It also shows the corresponding percentage of labeled particles by size

class found in samples at these and other various locations.

Referring to Table 1, the small tensile and compression forces ex­

erted in the feeders and under the roller preceding the superior clean­

er may be neglected. As a result of the impact forces accompanying the

p

Superior, impact and CMG cleaners, labeled material in the lint is dis­

lodged and falls into the waste streams. As the impact force increases

more than two-fold from the Superior cleaner to the impact cleaner,

the percentage of labeled particles tends to decrease in the 14/20 and

20/40 size ranges and increase in the 40/60 and -100 size ranges. This

is apparently the result of mechanical disintegration or micronization

brought about by impact forces. Consequently, the percentage of labeled

particles in smaller size ranges is expected to increase as the larger

particles disintegrate. It is observed that the percentage of labeled

particles in the large and middle size ranges in the waste sample from

the CMG^ cleaner remains essentially constant while the percentage of

labeled particles in the smaller size ranges decreases. This indicates p

that the significant tensile force exerted in the CMG cleaner does not

31

32

'

u a e 3C <«

1

w e

1

41 wl e 41 e o <_)

o <. — 41 b s 41 -« a . 41

w

9 I I

- 3 41 S — o 4; - •

« -3 O

^ oe u

' ?

M

a:

l / l

>

c

a :

§ 3 U

4>

e a u

X 1

b 9

• ^ • = .

41 a . 4) a

'

b • 41

•o * . _ 4> a OB

'

b s </• b =

41 U 'U ^ w - ^

« « e a oa u

'

b 41 : b «/• *•• b >a — u

X a

b b 9 » Ul = b £

^ 4J 31 •» -« - 3 b a = — a o

X a 1--

1

T

b 41

-3

11 —

•» 3

91 a s 3 a u

« = 9 »

3 « 4) « 4t m —

- 3 . ^ 1- 5 • ^ '^

a.

a

41 — ^ a —

\^^^^^ C «» « > 3 U

^ 3 l / l OC U l ^

>« X (A oe ua »

v ^

i

/

T

^-^

©

/ b

>

(e) \ ^

b J S

a i l ; « b )

i

e b m u

= -a 1* — c .* ^ — « X — — >.

1^ u

\

© j] b 9

M

3

S 1 b 9

Z

ae —

» 5 a a

O

in to <u u o s-

Q-

C71

33

%~ (O

Q-

• o OJ

1 —

0) .a tn

- J

^-o <u OT

cn £

• r -£ «o 0)

r—

n cj -M c -o 0) < j

s-Qi

Q .

T3 C rtJ

•u a>

+ j

s-<u X

UJ

£ to

CT. C

• r -C O) CL

o c:

' 1 —

CO to 03

r-" CO O (U CJ s-o

(U N

• r-LU C/O

<u

(TJ

Perc

enta

ge of La

bele

d Pa

rtic

les by Si

ze Class

1

-100

60/100

40/60

20/40

14/20

10/1

4 •10

P** I

• 1 '

1 1

0.14

7 X

<_ 0.246

X o CM

^ • CM O

d v|

0.420 X

<_ 0.833

0.833 X

1

1.16

8 1.168 X

< 1.

651

m

a X

Samp

le

Forces Ty

pe

<*-

Loca

tion

1 1 1

1 1 1

0.59

0.43

6.64

10.9

Lint

Te

nsil

e

CM

Feed

ers

o

.32

o 0.50

3.11

o

0.42

Wast

e Co

mpre

ssio

n

-

Impa

ct

0061

Supe

rior

Cl

eane

r

0.01

0.19

0.17

0.44

1.05

o

0.68

Wast

e Im

pact

5800

Impa

ct

Clea

ner

o

0.10

o

0.50

0.79

o

0.47

Wast

e Te

nsil

e 9900

Impa

ct

8300

CMG"

Clea

ner

0.02

o

o

0.27

2.90

o

o

Lint

No

ne

Afte

r Cl

eani

ng

0.03

0.07

o

0.22

o

5.56

o

Filt

er

Wast

e No

ne

Vacu

um

Bag

34

CO

OJ

o + j

i -Q_

o

(a +->

O E S - - f -

a. o - o Q_ d to c

• o

<u 4 J

s-0)

t o CO t o —

X o L U

t o d)

u s-o u.

<v N • ^ •

OO

>. J:::

CM

<D

.n (O

1 1

1 ^ 1" 1

o o —

wl

^ ^ ^ u

M

- > . 1 41

U

. r f

•3 9

i j

i s o

3

S r a

•4 O — 1 -- J

> O

u 9 . r f S 9 ••J b 9

&

"* »

1*

X %0

^ - ^ <NJ

^ • O v l

w O CM

3 • »

r v O

O v l

n <n f^

o a c>* • » o a wl

t a t

1 ^ .— i . | .

5 ".-— 1 3 v l

1 1 1 >4 * "

\a V 9 <a

—I a .

1

a •

m >d

IT

9

i. M

.« W^

I/I 4J 1.10

i. > i

ion

^ <J

o a

a

CM <M

a

a

9 1

a a

a

a

4 ^

~ .a

41

wl e 9

<M

b 9

-3 a . u ^ - i

a a

a

a

a

1/1

a

a

a

. s .u

9

1

V '•>

3 * 3 —

— •« ^ ^ = :i

u/l

a

1/1 N

a

s a

a

s (M

1/1 a i

3 '

31 (M

a

9 •irf Wl

« Z

.rf u 4

a-

3 *

^ z ^ q

3 a

1 1 1

31 l a oia dia

1

eMl<— — ' / n

Old 1 I

Ol

d

_

0

« O H n

d

i- i 4

CM

a

0

« ^

SI 0

d

9

Wl

« 3

a z

a

a

b 9 «

*. . . - wl

>- « U. 3

S S

b 9

^ ^ zj 9 •3 — "3 •3 -4 C

— 9 a

= a u

^*

d

a

a

a

—

-•

a

a

c

.

9

3

b b 9 9 i -3 — •— -3 ^

< a a

p . . a d

a

a

a

^1 0

d

<o

m

^ m

«

f . 1 CM

a

9 .w l A

* 3

^ M

« X

5 s CM

9 S b ^ 9 >l ^ b -3 — 9

^ a

5 a

0

. a

0

a

a

0

b 9 9

. .. . — w l

— ^ '— 3

9

1

b ' - 9 9 2 .£ :/ V .<. — -3 '.. ^ c ii5 3

•

=>

a

a

a

a rifc

CM

a

a

a

./ s

.

3 wl wl 9 b

s-

b

-3 S Jt 9 —

^ 3 J a

••[

a

3

a

a

cn i-i

cn cn

1

3

£

.

ii 1

U

u J^

'^ & --*

35

result in as great a disintegration of particulate matter as does the

impact force. Comparing lint before and after cleaning, the percentage

of labeled particles in the large size ranges has decreased due to the

cleaning operations noted with a corresponding increase in percentage

of labeled particles in the 14/20 size range. This is most likely also

due to micronization. Referring to Tables 1 and 2, it is evident that

a further decrease in the percentage of labeled particles in the lint

occurs as a result of filtering action at the second condenser.

It is observed (Table 2) that the tensile force exerted in the

feed hopper is negligible. Referring to Table 2, as a result of the

impact force accompanying the blade beater, labeled material is trans­

fered from the lint to the waste stream. Compared to the preceding D

waste stream at the CMG cleaner (Table 1), the blade beater waste

stream shows that the percentage of labeled particles decreases in the

largest (+10) size fraction with a corresponding increase in all but

one of the smaller size ranges. This further indicates that the impact

force creates smaller particles by disintegrating the larger ones.

Additional evidence is found by following labeled material into the

respirable range (Table 3). The percentage of labeled particles in

the respirable sample collected nearest the blade beater (VE2) is

twice as large as in the respirable sample collected next to the feed

hopper (VEl). A significant decrease was observed in the percentage

of labeled particles in the larger and smaller size ranges in the

waste stream from the Kirshner beater. A three-fold increase was also

noted in the percentage of labeled particles in the respirable dust

sample collected at the Kirshner beater (VE3 vs. VE2, Table 3). This

36

Table 3

Percentage of Labeled Particles in Respirable Airborne Dust

Dust Percentage Sampler Location Labled Particles

VEl East of feed hopper 0.27

VE2 East of blade beater and blade beater condenser

VE5 In front of doffer and between cards

VE6 In front of doffer and next to coiler

0.54

VE3 East of Kirshner beater and i ^2 Kirshner beater condenser

VE4 East of calender rolls 0.80

0.97

0.37

37

corresponds to a three-fold increase in impact forces (Table 2) from

the blade beater to the Kirshner beater, further indicating a relation

between impact force and harmful dust emissions. Since undyed leaf­

like material behaves like BY 37-dyed leaf (19), these results indicate

that the percentage of all light, friable particles, such as leaf and

bract, are micronized into the respirable range in direct proportion

to the magnitude of the impact forces exerted.

Comparing the lint samples before and after the blade beater, it

is found that the percentage of labeled particles has increased in both

size ranges containing labeled particles. This apparent de novo gen-

eration may be explained by considering the disintegration of the parti­

cles. Due to the greater surface area of the larger particles, one

large particle can be broken up into numerous smaller particles. Thus

one large particle in the lint sample before the blade beater could have

been missed in counting and have been broken up into the high percentage

of labeled particles after the blade beater. This is also the case

with the sample of lint at the calender rolls and the picker lap, which

also indicates de novo generation of smaller particles. It should be

noted that in both cases only one labeled particle was found in each

sample. The reason larger particles may have eluded counting is un­

doubtedly due to sampling error. In any case, the results indicate

that friable particles are broken up and that the percentage of labeled

particles increases in the lint as it follows the flow path through

picking (Table 2). Referring to Table 3, it can be seen that the per­

centage of labeled particles in the respirable range decreased at the

calender rolls (VE 4). This is expected since compressive forces are

38

applied which act to entangle the fibers and trap the particulate

matter.

Finally the data in Table 4 indicate that the percentage of label­

ed particles in the total dust samples collected by the stationary high

volume samplers (SHV) increases down the flow path. It should be noted

that the roving high volume samplers (RHV) were placed on movable mounts

in order to assist in locating the dust emission points in opening,

cleaning and picking rather than accurately measuring those emission

levels. The equipment blower filter samples (EBFl and EBF2) represent

a better measure of the emissions as the cotton flows through the open­

ing and cleaning sections. The stationary high volume results in

Table 5 also indicate, as do the results in Table 4, that friable,

leaf-like dust emissions increase as lint proceeds from opening through

picking.

Referring to Table 5, it is observed that the percentage of labeled

particles steadily decreases in the waste and lint as the lap moves

from the licker-in to the sliver end of the cards with the great major­

ity of the waste falling out under the licker-in. In addition, the

data in Table 4 show that the percentage of labeled partioles, and thus

the percentage of leaf-like material, decreases in the total dust samples

as the picker lap moves from the licker-in toward the sliver end of

the cards. Apparently, this is the result of leaf (and by inference,

bract) disintegration not being as great in carding as in opening,

cleaning and picking due to the lack of impact forces. More trash, in­

cluding labeled particles, is removed at the inlet to the card and less

emitted as airborne particulate matter. As evidence. Table 5 shows

39

Table 4

Percentage of Labeled Particles in Total Airborne Dust

Dust Sampler

SHVl

SHV2

SHV3

RHVl

RHV2

RHV 3

RHV4

RHV5

RHV6

RHV7

RHV8

RHV9

RHVIO

RHVll

EBF2

EBFl

Location

North of feeders

East of superior cleaner

Southeast of calender rolls

East of feeders

Underneath superior cleaner

Northwest of impact cleaner

North of CMG* cleaner

East of feed hopper and superior cleaner

East of blade beater and feed hopper

East of blade beater condenser

Behind and to the side of licker-in

Beside main cylinder

In front and to the side of

During clean-up

doffer

South of impact and CMG cleaner

East of feed hopper

Percentage Labeled Particles

0.44

1.78

3.07

1.44

0.28

0.56

1.06

0.87

0.0

0.0

1.70

0.70

0.33

3.33

0.56

0.23

40

to a; o

a. -a OJ

<D

cn «3

4->

e (U

u s-

o^ £

• 1 —

O) T3 Q -

T 3 E 03

• a

cu 4->

s. QJ X

IJJ

t o (U

o s-o

s-to

o E

•^ to to to

t —

C J

(U N

' 1 —

OO

> v Li_ ja

m

in

Qi r ^ j a ro

1 1

*A CA

Cla

tti N

..» 1 / 1

>( . C I

les

u " 4 . ^

b • 9

a . •o «* i! •e

- J

l b .

O

« j

w « c 0 1

u b OJ

a .

o o

1

o o

60/1

o « >. o

o * r > i O CM

O C M

" V

• r C^ O

O

• • •

l / l

rce

o u.

p ^

4 r

m.

0.1

* V

X

X \o T

r^ CM

Z6 • o v l

X o C M

O V

«• • CM O

d v l

X CW>

cn O CO CM • •»• O

d v l

X eo

cn • * * " d v |

X <— l / l

CO vo l O •

. •— v l

. m l O

• c

X

w ^ c • 9

( O

SJ

o. >. H -

.a

1 * .

c o ^ A J

« u o

_ J

o

d

C O

o

d

o

m C O

d

» ^ H

•

( M

O C M

^

U l

«r •

OJ * J l / l

a 3

0 )

~ ^ K

V I

c 01

• -

2800

c ^ v

i b 0 1

J <

u ^ v

—J

«o

d

vo C M

d

o

n en

a

o

o

o

o

*J

c . - J

0 1

c o z

l / l * i

« _ u.

CM

o d

^ o

d

o

o i m

d

o

o

o

OJ *J l / l

<a X

0)

* M

c OJ

•—

38300

"O C i . « OJ

T 3 l/l C

•4J C •»-19 . . - —

^ Z (_>

O

d

o

o

o

o

o

o

4 J

c ~ - J

OJ

^ K

V I

c 0 )

h -

38300

e b — OJ

b 19 - O OJ z c

> b . •4-

<*. -o — O C 3^

O 19 U

o

m o

d

o

=»

o

1 1 1

o

*J

c » _ i

0 )

. V I

c OJ

• —

<-

b 0 )

> .^ w^

1 / )

I

I D

o o

o

o

o

o

o

«o o

d

OJ * i V I 19

Z

OJ

c o z

. I t e

3 3 0 1

c Q .

1 1 1 1 ^ 1 o 1 d !

o

o

o

o

o

o

b OJ OJ *i *j •— VI — CO b . 3

« C

o z

. 1 * -

5 ' « OJ 0> * « b

c - : o a. z 1/

o

d

o

o

o

o

o

o

b 01 OJ

4-> * J >— Vl — >a u. X

0 1

c o z

•^ «-9 e

i *' 0) a . b

c o U Q . • - 1/1

41

that the percentage of labeled particles in the waste sample collected

at the flats and main cylinder is much less than that in the waste

sample collected at the licker-in. The trash, including labeled parti­

cles, is removed from the lint primarily on the inlet side of the card.

Thus, there is less opportunity for it to be disintegrated by the flats

and converted into airborne particles.

R

The Pneumafil samples (Table 5) represent a good measure of poten­

tial airborne particulate matter captured at the card. Because most

particulate matter is removed at the card inlet, the percentage of

labeled particles (and thus, the percentage of light, friable particles)

is much less in the sample of sliver (Table 5) than in the sample of

picker lap (Table 2). The percentage of labeled particles is less in

the high volume sample collected at the doffer (RHVIO, Table 4) than in

the roving high volume sample collected at the licker-in (RHV8, Table 4)

It appears that the cards clean the picker lap without much of the ac­

companying emission problem present in opening, cleaning and picking.

The vertical elutriator results at the end of carding (Table 3) differ

because one was situated between the two cards in use (VE5) while the

other (VE6) was opposite the end of card 4. These results also indi­

cate that the percentage of labeled particles (and presumably all light,

friable particles) micronized into the respirable range is less in

carding than in picking.

Particles emitting a bright yellow fluorescence were found on all

vertical elutriator samples. This demonstrates the feasibility of

tracing the micronization of gross components of cotton trash into the

range of particle capture by the vertical elutriator (VE) cotton dust

sampler.

CHAPTER VI

CONCLUSIONS AND RECOMMENDATIONS

The ability to follow the micronization of fluorescently labeled

cotton leaf into fine trash and airborne particulate matter in the early

stages of cotton textile manufacturing, opening through carding, has

been demonstrated. Labeled particulate matter was found in all elutri­

ated dust samples, clearly demonstrating the feasibility of easily and

accurately following labeled botanical constituents through successively

finer micronizations into the respirable range. Based on the engineer­

ing analysis, it is concluded that the relative severity of fugitive

cotton dust emissions and the forces exerted on the cotton during the

early stages of cotton textile manufacturing are related.

This work should be repeated, starting with ginning, employing

bract as the labeled material in sufficient quantity (1 or 2 weight

percent) to allow tracing through weaving. To simplify the identifica­

tion of de novo particle generation, a narrow size range of large parti­

cles (2 mm - 12.5 mm) should be used. A single sampling procedure which

would yield a permanent record, applicable to the entire size range

of macro-samples, should be developed. A total material balance should

be made in all future work so that the amount of bract micronized in

any portion of cotton ginning or textile manufacturing can be quanti­

tatively determined. The results from the present study should be used

to define the direction for process machinery improvement aimed at de­

creasing dust emissions and improving the efficiency of existing occupa­

tional dust control technology in textile mills.

42

REFERENCES

1. Bethea, R. M.: Air Pollution Control Technology, pp. 61-94. Van Nostrand Reinhold Company, New York, NY (1978).

2. Bethea, R. M., Rowlett, C. D., and Morey, P. R.: "Evaluation of a Fluorescent Dust Tracer Technique in Cotton Ginning." Am. Ind. Hyg. Assoc. J., 39.: 998-1008 (1978).

3. Bouhoys, A.: "Byssinosis in Textile Workers." Trans. N.Y. Acad. Sci., 28: 480 (1966).

4. Bouhoys, A. and Nicholls P. J.: "The Effect of Cotton Dust on Respiratory Mechanics in Man and in Guinea Pigs," pp. 75-85 in Inhaled Particles and Vapors II, Davies, C. N. (ed.) Pergamon Press, New York (1967).

5. Cocke, J. B., and Hatcher, J.D.: "Levels of Cotton Dust in Exper­imental Card Room As Influenced By Production and Processing Para­meters," pp. 395-415 in Cotton Dust, Proceedings of a Topical Symposium. American Conference of Governmental Industrial Hygie-nists, Cincinnati, OH (1975).

6. Corley, T. E.: "Basic Factors Affecting Performance of Mechanical Cotton Pickers." Trans. Am. Soc. Agri. Eng., 9.: 326-332 (1966).

7. Fischer, J. J., Battigelli, M. C , and Foarde, K. K.: "Microbial Flora of Weeds Commonly Found in Cotton," pp. 110-113 in Proceed­ings of Beltwide Cotton Production - Mechanization Conference Special Session on Cotton Dust, Dallas, TX (1978).

8. Gamble, J. F., Fischer, J. J. and Battigelli, M. C : "Alternative Methods of Exposure in Provacative Tests in Byssinosis: Prelim­inary Observations," pp. 110-130 in Cotton Dust, Proceedings of a Topical Symposium. American Conference of Governmental Industrial Hygienists, Cincinnati, OH (1975).

9. Graham, C. 0. Jr., Kingsberry, E. C , and Rusca, R. A.: "Factors Influencing Dust Levels During Cotton Processing." iransactions of the National Conference on Cotton Dust and Health, p. 45, School of Public Health, Charlotte, NC (1971).

10. Hatcher, J. D.: "Physical Characteristics of Cotton Dust Generated in Different Processing Areas of a Cotton Mill," pp. 271-283 in Cotton Dust, Proceedings of a Topical Symposium. American Confer­ence of Governmental Industrial Hygienists, Cincinnati, OH (1975).

43

44

11. Hocut, R. H.: "Engineering Controls For Cotton Dust in Yarn Manufacturing Plants," pp. 416-425 in Cotton Dust, Proceedings of a Topical Symposium. American Conference of Governmental Indus­trial Hygienists, Cincinnati, OH (1975).

12. Imbus, H. R.: "Experience With Medical Surveillance Programs," pp. 17-26 in Cotton Dust, Proceedings of a Topical Symposium. American Conference of Governmental Industrial Hygienists, Cincinnati, OH (1975).

13. Key, M. M.: "Criteria Document: Recommendations For an Occupa­tional Exposure Standard For Cotton Dust," U.S. Department of Health, Education, and Welfare, PHS, CDC, NIOSH, HEW publication No. 75-118 (1974).

14. McKerrow, C. B., and Schilling, R. S. F.: "A Pilot Enquiry Into Byssinosis in Two Cotton Mills in the U.S." J. Am. Med. Assoc, 177: 850-853 (1961).

15. Merchant, J. A., O'Fallon, W. M., Lumsden, J. C , and Copeland, K. T.: "Determinants of Respiratory Disease Among Cotton Textile Workers," pp. 27-39 in Cotton Dust, Proceedings of a Topical Symposium. American Conference of Governmental Industrial Hygie­nists, Cincinnati, OH (1975).

16. Morey, P. R.: "Botanical Trash Analysis of Raw Materials Used in the Cotton Garnetting Industry." Am. Ind. Hyg. Assoc. J., 4£: 264-269 (1979).

17. Morey, P. R., Bethea, R. M., Kirk, I. W., and Wakelyn, P. J.: "Identification of the Botanical Origin of Visible Wastes From the Shirley Analyzer," pp. 237-265 in Cotton Lust, Proceedings of a Topical Symposium. American Conference of Governmental Industrial Hygienists, Cincinnati, OH (1975).

18. Morey, P. R., Bethea, R. M., Wakelyn, P. J., Kirk, I. W. and Kopetzky, M. T.: "Botanical Trash Present in Cotton Before and After Saw-Type Lint Cleaning." Am. Ind. Hyg. Assoc. J., 37_: 321-238 (1976).

19. Morey, P. R., and Raymer, P. L.: "Fragmentation of Cotton Bract and a Technique for Detecting Bract in Cotton Dust." Agronomy J., 70: 644-648 (1978).

20. Morey, P. R., Sasser, P. E., Bethea, R. M., and Hersh, S. P.: "Use of Dyed Leaf in Studies on The Origin of Cotton Dust," pp. 97-104 in Proceedings of Beltwide Cotton Production -Mechanization Conference Special Session on Cotton Dust, Dallas, TX (1978).

45

21. Morey, P. R., Sasser, P. E., Bethea, R. M., and Kopetzky, M. T.: "Variation in Trash Composition in Raw Cottons." Am. Ind. Hyg. Assoc. J., ^: 407-412 (1976).

22. Morey, P. R., Wanjura, D. F., and Baker, R. V.: "Comparative Anatomical and Ginning Characteristics of Two Upland Cotton Culti­vators." Agronomy J., 66 : 820-822 (1974).

23. Parnell, C. B. Jr.: "Mass Concentrations and Particle Size Distri­bution of Dust in Cotton and Synthetic Fibers," Paper presented at the winter meeting of the American Society of Agricultural Engineers, Chicago, IL (1978).

24. Rylander, R. and Snella, M.: "Bacterial Contamination of Cotton As a Factor Determining Its Pulmonary Toxicity," pp. 101-109 in Cotton Dust, Proceedings of a Topical Symposium. American Confer­ence of Governmental Industrial Hygienists, Cincinnati, OH (1975).

25. Sinclair, S.: "The Cotton Dust Controversy," in Job Safety and Health. U.S. Department of Labor, Occupational Safety and Health Administration, ±1 4-12 (1976).

26. Sinclair, S.: "Views at Odds," in Job Safety and Health. U.S. Department of Labor, Occupational Safety and Health Administra­tion, i: 13-17 (1976).

27. Taylor, W. E. and Sasser, P. E.: "Steaming Lint Cotton For Control of Byssinosis in Cotton Textile Mills," Paper presented at the winter meeting of the American Society of Agricultural Engineers, Chicago, IL (1976).

28. U.S. Department of Labor, Occupational Safety and Health Admin­istration: Occupational Exposure to Cotton Dust, Federal Register, Vol. 43, No. 122, pp. 27350-27463, June (1978).

29. Vaughn, E. A. and Rhodes, J. A.: "The Effects of Fiber Properties and Preparation on Trash Removal and Properties of Open-End Cotton Yarns." Journal of Engineering for Industry, February: 71-76 (1977).

30. Wesley, R. A., Cocke, J. B., and McCaskill, 0. L.: "Effects of Condenser Drum Covering at Cotton Gins on Card Room Dust and Quality of Yarn Produced by Open-End Spinning," Paper presented at winter meeting of the American Society of Agricultural Engi­neers, Chicago, IL (1978).

31. Wessling, W. H.: "Genetic Plant Characteristics and Cultural Practices That Affect Trash Content in Cotton Fiber," pp. 199-200 in Cotton Dust, Proceedings of a Topical Symposium._ American Con­ference of Governmental Industrial Hygienists, Cincinnati, OH (1975).

APPENDIX

46

CALCULATIONS

Feeders and Feed Hoppers

Fy = E. = 1/2 mvVgc (tensi le force)

where: v = 1.2 f t / s -> v^ = 1.44 f t ^ / s ^

gc = 32.2 Ib^ f t / l b ^ s^

m = pV

where: p = 34 lb /ft m

(wood)

V = (length)(width)(depth)

V = (12 f t ) ( 4 f t ) (0 .05 f t )

V = 2.4 f t ^

34 lb m = m

2.4 ft^ = 81.6 lb.

E, =

f t "

(0.5) 81.6 lb

m

m 1.44 f t ' I f ^ s'

32.2 lb f t m

F- = 1.8 f t Ib^ = 2 f t Ib^

Roller

F = Ep = mgh/gc (compression force)

where: m = 50 lb m

g = 32.2 f t / s '

h = 0.0208 f t

47

48

gc = 32.2 Ib^ f t / l b ^ s'

50 lb. E =

P m

32.2 f t 0.0208 f t

F =1 .04 f t l b . = 1 f t l b . c t f

Ib^ s'

32.2 Ib^ f t m

Superior Cleaner

Fj = E^ = (1/2 mvVgc)jjg^^g^ * 6 beaters (impact force)

where: gc = 32.2 Ib^ f t / l b ^ s

m = pV

p = 490.75 I b ^ / f t ^

V = V 1 + V ., ^ annulus spikes

(carbon steel)

V 1 = Tr[(outer radius)^ - (inner radius) Jlength annulus

circumference _ 2.67 f t where: outside radius =

and;

27T 2TT

outside radius = 0.43 ft

inside radius = 0.43 ft - 0.02 ft = 0.41 ft

length = 2.55 ft

V , = Tr[(0.43 ft)^ - 6.41 ft)^]2.55 ft annulus

annulus

spikes

V -I spikes

= 0.14 ft^

+o^ spikes = [(length)(width)(depth)]per spike *26 ^^^;^^^p[u<

= [(0.33 ft)(0.03 ft)(0.08 ft)]*26

and: spikes = 0.02 ft

therefore: V = 0.14 f t ^ + .02 f t ^

V = 0.16 ft"^

49

and: 490.75 lb m = m

ft^

0.16 fr

m = 78.52 lb m

V = 0) • r

where: oo = 360 rpm (0.1047) = 37.69 rad

and

0.43 f t

rad r

V = 37.69 0.43 f t

E,. = (0.5) 78.52 lb

m

= 16.21 f t / s

.2 262.76 f t ' Ib^ s'

32.2 lb „ f t m

Fj = 1922.23 f t Ib^ = 1900 f t Ib^

Impact Cleaner

h = h ^ (1/2 mv2gc)^g^^g^5 + (1/2 mv /9c)g,^„^^^^ (impact force)

where* m. ^ = (135 lb ). ^ *7 beaters wrier c. '"beaters ^ m'beater

m. ^ = 945 Ib^ beaters m

m gr i = (300 lb ) . J *7 grinders nders ^ "'m-'grinders ^

m . . = 2100 Ib^ grinders m

and: V = oj • r

where: cu^^g ters ^ ^^^ ''P'" (0.1047) = 33.92 rad

50

'•beaters = °- ^^ ^^

(jJ grinders = ^10 rpm (.1047) = 2 1 . 9 9 ^

V i n d e r s = °-^^ ^^

rad. ^beaters^ (33.92 i f )(0.38 f t )

V a t e r s = ^2.89 f t / s

rad. V i n d e r s = (21.99 ^ ) (0.46 f t )

^nv^-in/Hnv^c = ^0.^2 f t / S

grinders

E.. = (0.5) 945 Ibj^ 166.15 f t ^ Ib^ s'

(0.5) 2100 lb m

102.41 f t2

32.2 Ib^ f t m p

Ib^ s"

32.2 Ib^ f t m

Fj = 5777.53 ft Ib^ = 5800 ft Ib^

CMG^ Cleaner

T = kT = (/2 '''^^^'hic^er-in " ' ^ mv^/gc)^^^^^,

2 ) + (1/2 mv /gc^str ipper

Fj = E J = (1/2 mv / gc ) , i , | , e , . i n

(tensi le force)

(impact force)

where: m^. , • = 595 l b „ wiicic. " ' iTcker-in m

m , = 170 l b „ worker m

m ^ . = 170 Ib^ str ipper m

and: V = (jj • r

where: w l i c ke r - i n ^ ^^^ ^P" (0.1047) = 44.81 rad

^worker = ^^ ' P' (0.1047) = 57.59 ^ ^

'^stripper " "'^^ ''P" (0.1047) = 10.47 rad

' l i cke r - in " °-^^ ^^

"worker = ^'^^ ^^

S t r i p p e r = ^'^^ ^^

V = 44.81 rad l i c ke r - i n s ^-^^-^= 30.02 f t / s

V = ''Q'47 rad str ipper s

0.42 f t = 4.40 f t / s

595 l b „ E^^ = (0.5) ^

901.2 f t ' Ib^ s'

170 lb + (0.5) 21

585.16 f t '

32.2 lb „ f t m

Ib^ s'

32.2 lb „ f t m

170 Ib^ + (0.5) ^

19.36 f t ' Ib^ s'

32.2 lb f t m

F-j. = 9922.09 ft Ib^ = 9900 ft Ib^

and Ej j = (0.5) 595 lb

m 901.2 ft' Ib^ s'

32.2 lb ft m

Fj = 8326.30 ft Ib^ = 8300 ft Ib^

Blade Beater

Fj = E = 1/2 mvVgc (impact force)

51

where: V = w • r

CO = 940 rpm (0.1047) = 98.42 —

r = 0.67 ft

52

and V = 98.42 rad 0.67 ft = 65.94 ft/s

m = pV

where: p = 490.75 lb /fV m

and:

(carbon steel)

shaft " rings " ^studs " ^bars

^shaft " "•(shaft radius) length

shaft radius = ci'-cumference ^ 0^77_ft , 0 , 2 f t

length = 3.54 f t

and: ^shaft " "^(O-l^ f t ) ^ 3.54 f t

^shaft = 0-16 f r

V . = V . *5 rings rings r ing ^

2 2 V . = 7r[(outer radius) - (inner radius) ] length r i n g •• / j a

. . . ,. circumference 1.08 f t _ ry i-i ^^. outside radius = 2 —2T\

inner radius = shaft radius = 0.12 f t

and:

length = 0.17 f t

V . = 7r[(0.17 f t ) ^ - (0.12 f t )^ ]0 .17 f t r ing ^

Ving = °-°°8 '^'

53

Vings = °-°4 f t '

^studs = ^stud *10 '^^"^

stud ^ using top using bottom ^^ e l l i p t i c a l ares e l l i p t i c a l ares

^ s i n g top = ^ " ^^op * ^^"9^^ e l l i p t i c a l area

and: Area.^„ = TT a • b top

where: a-j. = 0.08 f t

b j = 0.05 f t

Area^Q = 7T(0.08 f t ) (0.05 f t ) = 0.01 f t ^

length = 0.47 f t

V . ^ = (0.01 f t^) (0.47 f t ) = 0.005 f t ^ using top e l l i p t i c a l area

V . . 4. = Area. ^^..^„ * length using bottom bottom e l l i p t i c a l area

and: Area. .^ = TT a • b dnu. ""=°bottom

where: ag = 0.09 f t

bo = 0.05 f t D

Area, , , = Tr(0.09 f t ) (0.05 f t ) = 0.014 f t ^ bottom

length = 0.47 f t

54

V . , ^ = (0.014 ft^)(0.47 ft) = 0.007 ft^ using bottom ^ e l l i p t i c a l area

and: V ^ • = (0.005 f t ^ + 0.007 f t ^ ) / 2 = 0.006 f t ^ stud ^

^"^^ ^3^^^^ = 0.006 f t ^ * 10

^ t u d s = 0-0^ ' ' '

Vbars = bar *2 bars

^bar = ^"^^of trapezoidal face * ^^"^th

and: Area^^ trapezoidal face = H " ^ ^

where: a = 0.14 ft

b = 0.17 ft

h = 0.04 ft

Area . = (Q-^^ f t ^ 0.17 ft^Q p^ ^^ '^^^^of trapezoidal face ' 2

Area . • ^ -, ^ = 0-006 f t ^ ^•^^^of trapezoidal face

length = 3.42 f t

V. = (0.006 f t^ ) (3 .42 f t ) = 0.02 f t ^ bar ^

V = 0.16 f t ^ + 0.04 f t ^ + 0.06 f t ^ + 0.04 f t

3

m = (490.75 l b ^ / f t ^ ) ( 0 .3 f t ^ )

so:

and: V = 0.3 f t

55

• • •

m = 147.23 Ib^ m

147.23 l b „

L^ - [0.:,)

4348.08 f t

s2

Fj = 9940.33 f t Ib^ = 9900 f t Ib^

Kirshner Beater

2 2 Ib^ s"

32.2 Ib^ f t m

Fj = E^ = 1/2 mv'^/gc (impact force)

where: V = 03 • r

03 = 880 rpm (0.1047) = 92.14 rad

and

r = 0.63 ft

V = 92.14 rad Q-^^ ^ = 58.05 ft/s

m = m _ _• + m. wood "'steel

m = P V wood ^wood wood

whe^^- Pwood = " ^^m^^^^

^wood " ^wood bar wood bars

^wood bar "- "'^of trapezoidal face * ^^"^th

= (lL±_b)h ^^^^of trapezoidal face ^ 2

where: a = 0.46 ft

b = 0.50 ft

h = 0.07 ft

56

Area . , ., , , = (0.46 ft H- O.50 ft.^ .^ .. of trapezoidal face ^ 2^ jU.UZ ft

Area of trapezoidal face " ^'^^^ ^^'

length = 3.42 f t

and: ^wood bar = (0-034 f t^) (3.42 f t )

^wood bar " 0 . 1 2 ft^

^wood = (0-12 f t ^ ) * 3

^wood = 0-36 ^ '

and: m . = 34 —? wood ,^3 ft^

0.36 f t '

m,, . = 12.24 lb wood m

m steel ^steel steel

"here: p^^^^, = 490.75 I b ^ / f f

Steel shaft rings bars studs

where

^shaft ~ '^(^'^^^^ radius) * length

ch.^+ v1=/ -;Mc - circumference _ 0.65 ft shaft radius - TT- TT-

shaft radius = 0.10 ft

length = 3.58 ft

and: V . . = 7T(0.10 ft)'^(3.58 ft) snatt

^shaft = 0 - " '"•'

57

. V ings = V i n g *^ "^"^s

2 9

^ring ^ "^[(outer radius) - (inner radius) ] length

where: outer radius = shaft radius + 0.073 f t

outer radius = 0.10 f t + 0.073 f t

outer radius = 0.173 f t

inner radius = shaft radius = 0.10 f t

length = 0.25 f t

^r ing " ^[(0-173 f t ) ^ - (0.10 f t )2]0.25 f t

^ i n g = 0-016 f t ^

and: V^.^^^ = (0.016 f t ^ ) *4 = 0.064 f t ^

^bars = bar ^ t)ars

where: V ^ ^ = Area^^ trapezoidal face * ^"^th

^"^^of trapezoidal face " (~-2~)'^

where: a = 0.46 ft

b = 0.38 ft

h = 0.19 ft

_ ,0.46 ft + 0.38 ft^n TO f^ Area ,- - ^ -^ ^ - ( o )0.19 ft

of trapezoidal face ^ 2 ' Area ^ . -^ ^ ^ = 0.08 ft^ of trapezoidal face

length = 3.42 ft

58

" - V. ^ = (0.08 ft2)(3.42 ft) bar

Vbar - 0-27 ft^

^bars = (0-27 ^ i ) * 3

^bars =0-81 ft^

^studs = V^tud *12 studs

where: V^^^^ = Area^^ trapezoidal face * l«"9th

' '" of trapezoidal face " ( ^ — ) h

where: a = 0.10 ft

b = 0.17 ft

h = 0.21 ft

Area , , ., , , - (0-10 ft ^ 0.17 ft^^^^ of trapezoidal face ^ 2 '

Area . ^ - i ^ = 0.028 ft^ of trapezoidal face

length = 0.25 ft

and: V^^^^ = (0.028 ft2)(0.25 ft)

V ^ . = 0.007 ft^ stud

V , . = (0.007 ft-^)*12 studs

V ^ . = 0.084 ft" studs

and: V^^^^^ = 0.11 ft^ + 0.064 ft^ + 0.81 ft^ + 0.084 ft^

and:

^steel =1.068 f t '

490.75 lb m m

steel f t '

1.068 f t '

m^,^^^ = 524.12 Ib^

so: m = 12.24 lb + 524.12 Ib^ m m

m = 536.36 lb m

E = (0.5) 536.36 lb

m 3369.80 f r Ib^ s'

32.2 Ib^ f t m

Fj = 28065.62 f t Ib^ = 28100 f t Ib^

Calender Rolls

^c = " k (compression force)

W = fx

where: f = ma/gc

m = m. + m, weights bars

m. . u.. = m ^.^UH- *2 weights "weights weight

m . u^ = 58 lb„ weight m

so: m .nnh+c = (58 lb^)*2 = 116 lb weights ^ m m

'"bars (^steel^^bars

59

where: p^^^^^ = 490.75 Ib^/ft'

Vu = V. *2 bars bars bar

60

^h;,y = Tr(average radius of bar) * length bar

average radius of bar = .125 f t

length = 1.75 f t

^bar = " " ( - l ^ ^ f t )2*1.75 f t )

^bar = 0-086 f t '

^bars = 0.086 f t ^ * 2

and

V. = 0.172 f t ' bars

490.75 lb m

m bars ft^

0.172 f t '

m = 84.41 Ib^ bars m

so m = 116 Ibj^ + 84.41 Ib^

m = 200.41 lb m

and: a = 32.2 f t / s '

gc = 32.2 lb f t / l b ^ s

so:

200.41 lb f = m

32.2 f t Ib^ s'

32.2 Ib^ f t

f = 200.41 lb.

and: X = 6.33 f t

61

so: W = (2-0.41 lb^)(6.33 f t )

W = 1268.60 f t Ib^

'^ -' i^-i ^^1 where i = compression steps

Ek = 1/2 m^V ' /gc

m.| = pV * 2

where: p = 490.75 Ib^/ f t^

V = TT(radius of r o l l ) * length

radius of r o l l = 0.21 f t

so:

and:

length = 3.33 f t

V = Tr(0.21 f t )2(3.33 f t )

V = 0.46 f t ^

lb m. = 490.75 — ^

' f f ^

0.46 f t ' (2)

m = 451.49 Ib^

so

V = 0.23 f t / s

451.49 lb

ki = (°-^'-m

0.053 f t Ib^ s

32.2 Ibj^ f t

E l , = 0.37 f t Ib^ kl

E 2 = 1/2 m2V2 /gc

m2 = pV * 3

62

where p = 490.75 Ibj /ft'

V = 0.46 fV

so:

so

lb_ m / i o n "7cr m.p - 490. /b -

^ fV

0.46 f f^ / I N

m^ = 677.24 Ib^

V2 = 0.23 f t / s

677.24 Ib^ r (n r\ ^

k2 ~ ( - ^

0.053 f t ^

s'

2 Ib^ s^

32.2 l b „ f t m

E 2 = 0.56 ft Ib^

hs - 1/2 V 3 /9C

m3 = pV * 4

where: p = 490.75 lb /ft m'

so

so:

V = 0.46 f t "

490.75 Ib^

'•'3 - f t 3

^3 = 903 Ib^

v , = 0.23 f t / s

0.46 ft'^ (4)

903 lb

Ek3 = (°-5) m

0.053 ft' Ib^ s

32.2 Ib^ ft

E,, = 0.75 ft lb,

E. = 0.37 ft lb, + 0.56 ft lb, + 0.74 ft lb,

E, = 1.67 f t l b .

F = 1268.60 f t l b , + 1.67 f t l b .

63

F = 1270.3 f t l b , = 1300 f t l b .

L icker- in

F = E, = 1/2 mvVsc (tensi le force)

wher •e:

and:

where:

so:

so.

• • •

Flat

^T =

s and

m = 175 lb m

V = 03 • r

03 = 730 rpm (0.1047) - 76.43 ^^^

r = 0.42 f t

\! - If, Ari ^^^ V / D . H-O •

S

V = 32.1 f t / s

0.42 f t

\

175 Ib^

k ~ ^ '

1030.41 ft"^

2 s

E| = 2800.03 f t l b .

2800.03 f t l b , = 2800 f t l b .

Main Cylinder

l b , s^

32.2 l b „ f t m

' T ^k f l a t s "*" k main cylinder (tensi le force)

64

where V = 0.005 f t / s

m = m,:, . * 110 f l a t s TI a t

and; " 4^1^+ - 7.5 l b „ f l a t m

so: m = 7.5 lb * 110 m

so:

m = 825 lb m

^k f l a t s = (0.5) 825 lb

m 0.000025 f t ' l b , s'

32.2 lb f t m

k flats = °-°0°3 f t Ibf

^k main cyl inder = 1/2 mv /gc

where m = 1800 l b m

where:

V = 03 • r

03 = 170 rpm (0.1047) = 17.8 rad

so:

r = 2.08 f t

V = 17.8 rad 2.08 f t

1800 lb m

V = 37.02 f t / s

E . T ^ = (0 .5 ) • k main cylinder

F n. ^ = 38305.35 f t l b . " k main cylinder T

1370.48 ft' lb, s'

32.2 lb ft m

F.. = 0.0003 ft lb, + 38305.34 ft lb.

F- = 38305.34 ft lb, = 38300 ft lb.

Doffer and Main Cylinder

F = E + E T k main cyl inder k doffer

^k main cyl inder = 38305.34 f t l b ,

^k doffer = 1/2 "iv^/gc

(tensi le force)

65

where: m = 900 lb m

V = 03 • r

where: 03 = 8.57 rpm (0.1047) = 0.9 —

r = 1.125 f t

so: V = 0.9 rad 1.125 f t

V = 1.01 f t / s

^°^ ^k doffer = (0.5) 900 lb.

m 1.02 f t ' l b , s'

32.2 Ib^ f t m

^k doffer = 1^-25 ^t l b .

F = 38305.34 f t l b , + 14.25 f t l b .

F = 38319.59 f t l b , = 38300 f t l b .

Sl iver

' T " 2 * ^k doffer calender r o l l ( tensi le force)

E . ^ n = V2 mv' /gc ' k doffer calender r o l l

66

where m = pV

so:

and:

P = 490.75 lb / f t ' m

V = Tr(radius of doffer calender r o l l ) ^ * length

radius of doffer calender r o l l = 0.125 f t

length = 0.42 f t

V = 77(0.125 f t ) 2 0.42 f t = 0.02 ft-^

lb m = 490.75 m

f t '

0.02 f t '

m = 9.82 lb m

where

V = 03 • r

03 = 40 rpm (0.1047) = 4.19 rad

so

so

r = 0.42 f t

V = 4.19 rad 0.42 f t

V = 1.76 f t / s

9.82 lb E, = (0.5) m

3.1 f t ' l b , s'

32.2 lb f t m

E, = 0.47 f t l b .

F = 2(0.47) f t l b .

F-p = 0.94 f t l b , = 1 f t l b .