Zhantugulov T.Zh., Bolat  E.B.

Kostatanai state university  named after   À. Baitursynov,

the Republic of Kazakhstan

Research of extruding processes

At extruding of multi-component forage gets better its chemical composition and there are processes, similar with processes which are happening in the digestion organs of animal, that allows to direct forage energy to the structure of animal organism.

For improvement of extrudate quality we offered and made a billow of extruder, at the edge of  its screw, abuts to the corps, is made angularly in the direction of forage supply. In conducted studies are viewed the influence of different factors  on the magnitude of jamming angle: forage composition of its physic-mechanical state, the surface of  its slant was made smooth and ribbed, the billow diameter was   changing.

Experiments were conducted on the Box-Behnken and Rehshafner standard plans, processing of experiments results allowed to received  equalizations of regression.

According to the Box-Behnken plan (screw surface without slant)

Y = 4.9 + 2,05Õ1 +1,77Õ3 + 0,54Õ1Õ3 + 0,73Õ2Õ3 + 0,45Õ2Õ4 + 1,58(Õ1) 2 +0,79(Õ2) 2 + 0,73(Õ3) 2 + 0,8(Õ4) 2

Regression equalizations of the experiment conducted according to the plan of  Rehshafner is received by processing  through the program Matcad - 14(screw with the  slant angle)

Y= 9,06 +1,83Õ1+0,41Õ2+0,65Õ3+0,29Õ4+0,30Õ5-

0, 58Õ1Õ5+0,63Õ2Õ4+0,32Õ3Õ4+0,32Õ4Õ5+1,63Õ12-0, 84Õ22-

1,12Õ32+0,01Õ42-0,06Õ52

Adequacy of the received models was checked by the Fisher criterion. As a result of comparison of the models through the “Mathcad – 14” program we received optimization data:

For the basic variant (screw without a slant) Ymax=10.284kg/KW/h;

Ymin=0.549kg/KW/h

for the experimental variant(surface with the slant angle)

Ymax=13.219 kg/KW/h; Ymin5.051 kg/KW

At  the decoding  there were  received the optimal values of the  factors  at feed mix extruding : slant angle of screw surface is 5º, frequency  of extruder screw rotation is 60 rpm;  water content  in feed mix is 50%; the ratio between length toward diameters of filament extrusion device   2,34;  straw content in feed mix is 33%. As a result of the conducted experiments there were confirmed the theoretical researches (with the correlation coefficient 0,72). Comparison of experiments results of showed the efficiency increase of extruding by the worked out extruder at 20%, comparing with the basic variant. Further researches of  the extruders operation were directed to the comparable analysis, for this purpose the composition of feed mix was changed, there was applied a billow with a smaller diameter. As forage was taken a monoforage (i.e. mixture consisting of homogeneous in composition materials). Experiments were conducted according to the Pesochinsky standard plans (for the direct screw surface) and the Box-Behnken  plan  (screw surface with the  slant angle). As factors were accepted: frequency of billow rotation (Õ1) : humidity of  feed mix(Õ2);  the length of filament extrusion device  toward the sum of diameters of exiting output port (Õ3);  the slant angle of screw surface (Õ4).The levels of varying of factors are certain in an interval  from - 1 to 1 .

Realization of experiments data allowed to get  for comparisons of the productivity  of extruder  at  the direct  screw surface  with the  slant angle. At treatment of results of experiments equalizations of regression are received: According to the Pesochinsky  plan (direct screw surface)

Y=18.15+5.28X1+3.36X3+1.52X2X3+1.53X1-1.12X2² - 1.425X3²; kg/KW /h (3)

Ymax=27.90 kg/KW4; Ymin=6.485 kg/KW according to (surface slant)

Y=24-5.03X1+3.28X2+2.21X3+2.75X4+1.92X1X2+0.948X1X3+1.34X1X4+

0.99X1²+0.99X3²+2.62X4²; kg/ KW /h                                             (4)

Ymax=36.078 kg/ KW /h;

Ymin=6.485 kg/ KW /h.

where Y=Q/N kg/ KW /h; specific capacity of the extruder.                                 (5)

                                       

Q- capacity of the extruder, N – power, spent for the process.

The values of maximum and minimum specific productivity are received through the "Mathcad - 14" program, after processing of the equations (3) and (4).

At the decoding of factors values we received: frequency of billow rotation  of  the extruder(60 rpm); water content  in feed mix is (50%); the ratio between length toward diameters of the output ports of the filament extrusion device  (3); the slant angle of the screw surface (25 degrees). Researches confirmed the theoretical suppositions about the increase of the extruder productivity at the screw surface change with the slant angle in the direction of forage supply.

The composition of feed mix influences the slant angle of screw surface(at processing of monoration  it became 5 degrees, at processing monoforage it became 25 degrees).

Improvement of the extruder productivity at the increase of the filament extrusion device length toward the sum of output ports diameters.

 

Literature

1. Gavrilov N.V.  Abstract of thesis dissertation on the competition of scientific degree in engineering sciences. Orenburg 2005-p.19.

2. KurmanovA.K., Gavrilov N.V., Khasenov U.B. Smolyakova V.N.  Experimental researches of separate structural parameters of the extruder. Vestnik nauki of the KSU ¹2, 2004-p.51-53.