Design Data_Bucket Elevators

DENSITY & ANGLE OF REPOSE OF COMMONLY CONVEYED MATER1AI5

Material

Recommended max. angle of belt to horiz, deg. 6

Density tonne/m'

anthracite, fine, dry

0.8 - 0.95

45

gypsum, small lump

1.2 - 1.4

40

Clay, dry , lump

1.0

gravel

12

-

1.5

SO

1.5 -

1.9

45

1.2

45

1.3

45

earth, dry

foundrysand (shake out)

24-26

ash, dry

23

0.4 - 0.6

SO

lime stone, lump

20

1.2-

45

Coke

17

0.36 - 0.53

SO

Wheat flour

23

0.45 - 0.66

55

Oat

18

0.4 - 0.5

35

saw dust

27

0.16 -

dry sand

18

1.4 -

Wheat

18

0.65 -

iron ore

18-25

peat, dry lump

18

0.33

-

0.41

45

Coal (from mine)

18

0.65

-

0.78

SO

dry cement

20

1.0 -

1.3

SO

slag, anthracite

22

0.6

-

0.9

4S

9.22

1.25 -

1.5

0.32

39

1.65

4\

0.83

3\

2.1 - 2.5

SO

DESIGN DATA-PSGT

./

DESIGN OF BUCKET ELEVATORS Nomenclature

Equation

i.

a

=

Q

-3.6 vp~-

io

Capacity of each bucket, litre

a,

pitch of bucket, m == (2.5 to 3) h

h,

height of bucket at the belt or chain end, m

v,

belt or chain

p,

bulk density of conveyed material, tonne/cll.rn

..y,

bucket

0,

capacity of elevator, tonne/hr

loading

velocity,

m/s

efficiency, table.

I,

p. 9.24

i

; , values from table 2.

A,

p. 9.24

projection of bucket from belt face, mm

a",,,,, dimension of the largest lump of material conveyed, mm A""a",.." m m,

= 2 to 2.5 if 20% of material is of size ilm"" =4.25 to 4.75 if 50 to 100% of the material is of size am""

SIIIU, max. static tension in the belt, kgf. H,

ht to which the load is elevated, m

q,

wI. of load/ metre of elevator,

Klo

factor of resistance,

qQ'

wI. per meter of belt or chain with buckets, kgf/m == K2 Q

Sm.." = 1.15 H (q+K1q.)

q =

(For K2

kgf/m

see table 3, p. 9.25

see table 3)

N,

power, kw

Ka,

factor, see table 3, p. 9.2)

Q 3.6 v

Power on the drive shaft:

N

=

QH 367 (l.lS+K.Kav)

DESIGN DATA-PSG

TECH

9.23

v

PARAMETERS OF BUCKET ELEVATORS

I.

Table

Typical loads

Type of bucket

Type of elevator

Range of Speed, v, mls

Loading efficiency, '¥

0.6-0.8

Coal dust

slow speed gravity d is.:harge

D

0.85

Cement, chalk, fert ilizer

high speed centrifugal dis.:harge

D

0.75

I}5-1.8

D

0.7-0.8

1.25-2

Saw dust, dry clay in lumps, coal Gravel, ore, slag.

.Iow speed directed gr." ity discharge

V

0.7-0.85

0.8-1

Sand, ash, earth, rock

high speed centrifugal discharge

D

0.7-0.8

1.6-1.8

Moist chemicals, wet sand &c.,

high speed centrifugal dis.:harge

Sh

0.4-0.6

1.25-1.8

slow speed gravity discharge

Sh

-..-

-

D,

.. '-

d'C'ep; V,

Vec;

Sh,

SELECTlO

chain

belt

1.25-1.6 0.8-1

1.25-1.6 0.6-0.8

Sh:lIlow.

OF

BUCKETS:

based on io a Table 2. V buckets

Shallow buckets

Deep buckets

io a

.1 ..

io

bucket B mm

width,

. a I/m

io

2.5

0.75

-

-

-

-

135

3.67

J.I

2.17

0.65

9.4

1.5

160

6.67

2.0

3.67

11

-

-

200

8

3.2

6.5

2.6

18.0

3.6

250

15.6

7.8

14.0

7.0

31.2

7.8

350

25.0

15.0

50.0

16.0

450

85.0

34

600

134

67

750

206

130

900

24.2

~.24

10

litre

R5

-

DESIGN DATA-PSG

TECH

FACTORS

Kit

...

Kit

T~bJi':3;

-

Ka

Elevator type Conveying capacity

~

Belt

Q tonne/hr

Do"bl" .cb;\iQ

Single Chain Type of buckets.

j

v

D,sh

.y

D,sh

-

D,sh

K. upto 10

0.6

-

1.1

10to 25

'0.5

-

0.8

l5 to 50

0.45 '

0.6

0.6

50to 100

0.4

0.55

. 0.5

Over100

0.35

0.5

KI

2.5

Ka

1.6

f i

.'

1.1

1.2

0.85

.1

0.7

().

1.1

-

-

0.6

1),9

2

1.5

1.25

1.5

I.2S

1.1

1.3

0.8

1.3

O.X

DIMENSIONS & CAPACITY OF BUCKETS

Tolble 4.

.f

BUCKET j Type of bucItct

width B mtn

,

I,

height h mm

capacity io litre

bucket

deep

135-400

100-240

0.75-14.5

shaDow

160-450

100-285

(1.65-15

Vee

160-%0

155-620

1.5-130

DESIGN DATA-PSG

Slandard

300, 400. 500, 600

pih:h. a. 111111

-

o:hain

l

J

., 160, 200, 250. 315, 400, 500, 630:

100, 115, 160, 100. 250, .\1S. 400, 500, 630

~

TECH

9.25