RK

Plansifter RK-2 and RK-4 is designed for cereals sorting (cleaning from impurities, fractionation before hulling, selection of intermediate hulling and peeling products, sorting and products control) at cereals industry enterprises.

Plansifter RK-2 and RK-4 is designed in accordance with Technical Regulations in Ukraine TU U 14311353.002-98 for cereals sorting (cleaning from impurities, fractionation before hulling, selection of intermediate hulling and peeling products, sorting and products control) at cereals industry enterprises.


Specifications RK-4

Crop

Technological operation

Technical capacity, t/h   

Buckwheat

 

 

 

Oat

Panic grass

Rice

 

 

Barley

Sorting of 1st and 2nd fractions before hulling

Sorting of hulling products:

1 fraction

2 fraction

Groats control

Millet control

Separation of hulling products

Separation of peeling products

Middlings control

Preliminary groats sorting

Sorting of 1st groats No.

Middlings control

8

 

12

16

5,2

8

16

16

6,8

16

7

1,6

2) quantity of product inputs (sections) - 4

3) nominal size of sieve frames, mm 400800


4) total rated active sieves area, m2 13,5


5) body oscillations frequency, -1 (rpm), deviation max.0,17 -1 (10 rpm) 3,0; 3,2; 3,7; 3,8; (180; 190; 220; 230)


6) radius of the body circular oscillations, mm 28-22


7) air consumption for aspiration, m3/h 840-1080


8) aerodynamic resistance Pa (mm w.g.) 150-200 (15-20)


9) electric motor power, kW 3,0


10) overall dimensions, mm, max.

               length  2310

               width  1390

               height to the feed board  2370


11) weight, kg: gross weight  2417,

                        net weight  2415.


Plansifter is produced in 10 versions that differ by functional schemes of sections, which arrangement is shown on fig.1.2.


Specifications RK-2


1) plansifter technical capacity

Crop

Technological operation

Technical capacity, t/h

Buckwheat

 

 

 

Oat

Panic grass

Rice

 

 

Barley

Sorting of 1st and 2nd fractions before hulling

Sorting of hulling products:

1 fraction

2 fraction

Groats control

Millet control

Separation of hulling products

Separation of peeling products

Middlings control

Preliminary groats sorting

Sorting of 1st groats No.

Middlings control

4

 

6

8

2,6

4

8

8

3,4

8

3,5

0,8

2) quantity of product inputs (sections) - 2


3) nominal size of sieve frames, mm 400800


4) total rated active sieves area, m2 6,75


5) body oscillations frequency, -1 (rpm), deviation max. 0,17 -1 (10 rpm) 3,0; 3,2; 3,7; 3,8; (180; 190; 220; 230)


6) radius of the body circular oscillations, mm 28-22


7) air consumption for aspiration, m3/h 420-540


8) aerodynamic resistance Pa (mm w.g.) 150-200 (15-20)


9) electric motor power, kW 3,0


10) overall dimensions, mm, max.

            length  1920

            width  1100

            height to the feed board  2500


11) weight, kg: gross weight 1810,

                        net weight  1809.


Structure and Functioning


Plansifter is represented by modular cabinet construction with sliding sieve frames and consists of sieve body 9 (fig.1.4.1), supporting frame 21, balancing mechanism 6 and drive 3. Plansifter is suspended on steel ropes to suspensions 1 fixed on the ceiling frame. Body is divided into four sections by supporting frame baffles. Fifteen sieve frames 24 with trays 25 and collector* (*collector frame 6 in the scheme 3) are installed in the section 23 guides. Body exterior coats and sections guides form side bypass channels. Sections doors are equipped with double walls, which form bypass channels from the receiving side. On the opposite side, sections bypass channels are made in the form of removable distribution boxes attached to the sections rear pillars. Sieves are cleaned by rubber balls 27.


Inlet nozzles (feeders) 5 with guides, which allow uniformly divide initial product to inlet sieve frames of every section, are installed on the body. Inlet sleeves 16 are mounted to the nozzles 5 and receiving devices nozzles. Outlet sleeves 11 are mounted to nozzles 17 and 30, fixed on the body bottom, and to floor nozzles 12. Receiving boxes 2 are fixed on the receiving devices, which are suspended to the ceiling frame by holders 13 and rods 14. Air ducts, aspiration systems and gravity flow ducts for product supply are fixed on the receiving boxes. Supporting frame 21 is represented by integrally mechanical welded construction. Sections, side coating, bottom and ceiling are fixed on the supporting frame. Upper and lower bearing blocks of balancing mechanism 6, which sets plansifter in motion, are also fixed on the supporting frame.


Sieve frame (fig.1.4.2) is made of wooden bars. Frame is divided by bars into 4 cells. Boxes 2, which bottom is made like a sieve plate, are installed in frame cells. Box sidewalls do not have holes and serve to protect frame wooden parts against wear by cleaners. Cleaners, balls Ø 25 mm, are designed for sieves cleaning, and two cleaners are putted into each cell before fastening the sieves at groats mills. Sieve frames are accomplished in two versions: single and double-sided. In single-sided frames product that passed through the sieve is transferred only one way (to the one side channel); in double-sided to the both sides.


Tray is a sheet with bent ends on the short side and two angle elements attached from below, which serve to fix the tray in the sieve body section, to remove tray with frame from the section and to provide it necessary stiffness. Pile cloth pads are glued on longitudinal bars of the sieve frame to prevent mixing of separate product fractions, and to provide free movement of frames along sections guides. Flannelette pads are glued between frame and tray and on the middle bars.


Arrangement of balancing mechanism is shown on fig.1.4.3. Mechanism allows adjusting radius of the plansifter circular oscillations by changing balancer weight due to installation or removal of removable loads 2 and 3. Speed of the balancing mechanism is adjusted by removable pulleys on the electric motor of plansifter drive (see tab.2.2).


Plansifter body is driven by V-belt transmission from electric motor. Drive motor is installed on the bracket fixed on the cabinet. Belts tension is accomplished by moving the motor through plate slots with the help of tension bolts. Plansifter kinematic scheme is shown on fig.1.4.4.


Floor nozzles serve to receive separated product fractions from the plansifter body. Construction of nozzles blocks is shown on fig.1.4.5. Upper nozzles 1 are connected by fabric sleeves with body nozzles; lower nozzles have flanged edge for connection of gravity flow ducts by standard yoke clamps. There is an access hole closed with plug 2 on the upper nozzle, which serves for sampling. The base of nozzles is box 3, which after plansifter installation is poured with concrete. Holes in the box sides are designed for easy installation of nozzles.


Plansifter is driven by motor 1126 with power 3 kW, oscillations frequency 950 rpm.  Electric motor must be powered by three-phase AC mains with frequency 501 Hz, voltage 380 V. Plansifter electric scheme (fig.1.4.6) provides motor switching on and off, protection of the motor and electrical wiring against short-circuit currents, overload, rated voltage. KM starter, which connects motor to the power network with its contacts, is self-locking and triggers by pushing the button S B2. Stop the electric motor by pushing the button S .1.


Operational principle of plansifter lies in the parallel and consequent product sifting through plane horizontal sieves, which perform circular translation. Sorting process (fig.1.4.1) starts when product is supplied to sieves through receiving boxes 2 and receiving nozzles 5. Product movement inside cabinet construction is carried out in accordance with one of technological process schemes (fig.1.4.7) and depends on plansifter version.  


Product use


During plansifter operation process special attention should be payed to the following factors:


- uniform loading of all sections;


- tightness of the body to prevent dusting in junctions;


- contamination of one fraction to another;


- state of all oscillating units and details, quit operation;


- cleaning of sieves;


- aspiration efficiency, preventing steaming of the walls inside the body at an ambient temperature below 15C.


Efficiency of separation processes and extraction coefficient of fractions that passed through screen depends on initial product qualities, load and may be adjusted by regulation of plansifter kinematic parameters frequency and body oscillations radius. Setting an optimal kinematic mode of the plansifter should be aimed to succeed the best technological effect. Optimal kinematic mode of the plansifter is specified in tab.2 depending on initial product and technological process system. Plansifter amplitude of circular oscillations is adjusted by removable loads fixed on the balancer (fig.1.4.3). Dependence between body circular oscillations radius (1/2 of amplitude) and removable loads weight is specified in tab.2.1. Quantity of additional loads, which must be fixed on balancers, depends on the radius according to fig.2.3 and tab.2.1.

Table 2

Crop

Technological process

Kinematic parameters

Scheme No.

Product

passed through the sieve

failed to pass through the sieve

1

2

3

1

2

3

R.,mm

n,rpm

1

2

3

4

5

6

7

8

9

10

11

Rice

Separation of hulling products

25

190

4

middlings

 

 

mixture of kernels with grain

mixture of kernels with grain

kernels/meats

Separation of peeling products

25

230

4

chopped grain

 

 

groats

groats

mixture of groats and chopped grain

Middlings control

25

230

3

middlings

middlings

chopped grain

groats

 

 

Panic grass

Cleaning from coarse and fine impurities

26

220

1

fine impurities

cleaned grain

 

coarse impurities

 

 

Sorting by size

26

180

1

small grain

small grain

 

large grain

 

 

Millet control

26

190

3

chopped grain and middlings

chopped grain and middlings

millet

coarse impurities

 

 

Barley

Sorting of hulled barley 

25

190

2

middlings

 

 

 

whole grain

chopped grain

Sorting of crushing products 

25

190

4

middlings

 

 

grain

large groats

small groats   

Sorting of peeled barley

25

190

4

middlings

 

 

grain

large groats

small groats   

Sorting of pearl barley (preliminary)

25

190

1

middlings

 

 

peeling

groats No.1

mixture of numbers, besides No.1

Sorting of groats by numbers:    1,2,3

25

190

2

small groats

small groats

 

ready-made groats

 

 

4,5

25

220

3

middlings

small groats

 

ready-made groats

 

 

Middlings control 

25

230

3

middlings

middlings

small groats

large groats

 

 

Oat

Groats control

25

190

3

large crushed groats and middlings

large crushed groats and middlings

groats

coarse impurities

 

 

Buckwheat

Sorting of fraction before hulling 

23

190

1

small grain 

 

main fraction

difficultly separated impurities

 

 

Separation of hulling products

26

190

2

small groats

 

 

unhulled groats

kernels/meats

 

Peeled buckwheat control

26

190

2

small groats

 

 

difficultly separated impurities

groats

 

Small groats control

26

220

3

middlings

crushed groats

small groats

groats

 

 

Hulls control

26

220

4

middlings

 

 

hulls

hulls

small groats

Table 2.1

Variants of the loads sets

Additional load position on fig.2.2.9

Weight of one load, kg

Total amount of additional loads

Weight of all additional loads, kg

Total weight of balancing loads, kg

Body oscillations radius, mm

1

1

2,3

8

18,4

236

22,6

2

1

2,3

8

38,4

256

25,1

2

2

2,5

8

38,4

256

25,1

3

1

2,3

8

48,4

266

26,3

"

2

2,5

8

48,4

266

26,3

"

3

1,28

8

48,4

266

26,3

IV

1

2,3

8

68,4

286

28,0

"

2

2,5

8

68,4

286

28,0

"

3

1,28

8

68,4

286

28,0

"

4

4,9

4

68,4

286

28,0

During additional loads installation their weight and configuration on upper and lower balancers must be equal. In case of failure to do so, loads in bearing blocks are unfavorably distributed that breaks body or sieve frames horizontal movement and deteriorates effect of product separation. Required oscillations frequency of the plansifter is set by selection of electric motor replacement pulley in accordance with data specified in the table 2.2.

Oscillations frequency

Pulley diameter, mm

Nominal

Outside

180

190

220

230

120

126

145

152

128,4

134,4

153,4

160

Body oscillations radius is determined as follows. Fix clean paper sheet on the free area of the body roof. Touch the sheet with a sharped pencil, which must be fixed in special holder or holding it motionless in an outstretched hand. Pencil leaves a trace on the paper the trajectory of the plansifter oscillation, which is close to the circle. Measure the largest D1 and the smallest D2 distance between two opposite points of the circle and determine the average radius R by the following formula:


R = (D1+D2)/4


If it is necessary to reequip one or more sections from one functional scheme to another, customer can optionally receive necessary sets of replacement parts and, by its own resources and means, change plansifter to the desired version.


Appointment of replacement parts group sets:


Set 1 for modification of section scheme 1 to scheme 2;

Set 2 for modification of section scheme 1 to scheme 4;

Set 3 for modification of section scheme 2 to scheme 1;

Set 4 for modification of section scheme 2 to scheme 4;

Set 5 for modification of section scheme 4 to scheme 1;

Set 6 for modification of section scheme 4 to scheme 2.


Each set contains replacement parts for one plansifter section.

List of replacement parts group sets is specified in appendix.


Readjustment of the plansifter sections from one functional scheme to another should be carried out in the following sequence:


- remove corresponding bypass boxes or sheets with windows in door and cabinet sections, unscrew the fixing screws and replace them by necessary boxes and sheets with windows from the set of replacement parts. While replacing boxes and sheets, it is necessary to check carefully the absence of gaps in the joints of neighboring elements;


- fix the seal with glue 88- in accordance with Technical Standard of Ukraine 38-105.540;


- unscrew the nuts and remove guides, which must be replaced, remove or reinstall intermediate bottoms;


- to change movement direction of fractions that passed through sieve from single-sided trays of sieve frames it is necessary to remove the tray with frame and turn it to 180˚.