Subdual of stationary thresher machine for chopping resudies

RESULTS AND DISCUSSION 

A-Effect of some operational factors on percentage of cut length. 

1- oval slots area. 

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ton

h

kW

h

ton

ty

productivi

Machine

kW

t

requiremen

power

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 Misr J. Ag. Eng., July  2007 

  

                            

                                                        

 

 

512 

0

10

20

30

40

50

60

70

80

< 3.5

cm

3.5-10

cm

> 10

cm

< 3.5

cm

3.5-10

cm

> 10

cm

< 3.5

cm

3.5-10

cm

> 10

cm

Rice straw

Corn stalks

cotton stalks

Categories of Cutting length ,cm .

T

h

e

 c

u

tt

ing l

e

ng

th

 pe

rc

e

n

ta

ge

,%

.

oval slots area=4 cm2

oval slots area=6 cm2

oval slots area=8 cm2

Fig.(2):The relation between the cutting length percentage  and 

categories of cutting length at different oval slots area for different crop 

residues. 

The obtained results indicated that increasing oval slots area from 4 to 8 

cm 2 for concave decreased the cutting length percentage from 68.9 to 

64.5 % and 20.6 to 16.85 % of cutting length of <3.5 cm and 3.5-10 cm 

(first and second categories) of rice straw, from 72.5 to 65.3 % and 22.8 

to 20.1% of maize stalks and from 65.4 to 61.5 % and 27.5 to 25.4% of 

cotton stalks respectively. While third category (<10 cm) was increased 

from 10.5 to 18.65 % of rice straw rice straw, from 5.7 to 14.2 % of 

maize stalks and from 7.1 to 13.1of cotton stalks respectively at  1.5 

ton/h feed rate, 18.3m/s drum speed,14.3 % moisture content and 3 cm 

drum-concave clearance. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig.(2): the relation between the cutting length percentage % and 

categories of cutting length at different oval slots area for different crop 

residues. 

For feeding animals suitable cut length as average was 3.5, 3.2 and 3 cm 

for rice straw, maize stalks and cotton stalks respectively. While for use 

in composting the cut length was (5.2-7.8),(5.5-6.4) and 4.5-6.1) cm for 

rice straw, maize stalks and cotton stalks respectively.      

Rice straw gave the longest values of cutting length than cotton stalks or 

maize stalks at same operating parameters. 

---

 Misr J. Ag. Eng., July  2007 

  

                            

                                                        

 

 

513 

1

0

10

20

30

40

50

60

70

80

< 3.5

cm

3.5-10

cm

> 10

cm

< 3.5

cm

3.5-10

cm

> 10

cm

< 3.5

cm

3.5-10

cm

> 10

cm

Rice straw

Corn stalks

cotton stalks