Purpose:
Self-balancing plansifters РШХ-4.18, 4.22 and РШХ-6.16, 6.18 are designed for sorting into fractions by size of wheat grain at flour mills, and also on complete mills with a productivity of 0.8-2 t h. Plansifter can be used for sorting grinding grain of other crops.
Specifications:
| NAME OF INDICATORS |
РШХ-4.18 |
РШХ-4.22 |
РШХ-6.16 |
РШХ-6.18 |
| 1. Technical productivity (load) on the 1st torn system, t/h, not less |
16 |
20 |
22 |
24 |
| 2. Average recovery factor of all components, %, not less: |
|
| - on the 1st torn system (with a technical productivity of at least 4 t/h per section) |
64* |
| - on the 1st grinding system (with a technical productivity of at least 1.7 t/h per 1 section) |
95* |
| 3. Number of sections, pcs. (receptions) |
4 (4) |
6 (6) |
| 4. Number of receiving devices, pcs. |
2 |
6 |
| 5. Total nominal, useful area of sieves, m2 |
17,7 |
21,63 |
23,6 |
26,55 |
| 6. Body vibration frequency at idle speed, s-1(vibrations per minute, VPM) |
3,7 (220) |
| 7. Radius of circular oscillations of the body, mm |
40-45 |
| 8. Engine rated power, kW |
4 |
| 9. Overall dimensions, mm, no more |
|
| - body height (A) |
1 543 |
1 859 |
1 385 |
1 543 |
| - length |
2 960 |
2 960 |
3 950 |
3 950 |
| - width |
1 110 |
1 110 |
1 220 |
1 220 |
| - height to the receiving board (B) |
2 331 |
2 650 |
2 180 |
2 500 |
| 11. Weight, kg, no more |
2 200 |
2 500 |
2 700 |
2 900 |
* Indicator values for sorting wheat grain milling products.
** Based on technical performance.
Design and operation:
The plansifter is a cabinet-type assembly structure with pull-out frames.
The plansifter consists of a body, a bracket with a drive, doors, a fence, loading pipes, frames with pallets. The sieve body (pic. 4.1) is suspended on four steel ropes (10) with the help of hangers 2 to the ceiling frame of the production room. The ends of the ropes are fastened in locks 11 mounted on the side body brackets with wedges 24. Above the body of plansifter there are suspended from the ceiling, on rods 3 and holders 1, two or three receiving devices 4 (depending on the functional diagram). Under the body, on the floor, there are pneumatic receivers or floor blocks of branch pipes. The branch pipes of the receiving devices and the floor branch pipes are connected to the branch pipes of the body of the sleeves (4 and 22). The sleeves are fastened to the branch pipes with rubber rings sewn into the sleeves, or fixed with clamps. The body consists of a bottom, a roof, sidewalls with ribs, panels, a frame of the balancer bolted together. Transport boxes (14) (Fig.4.1) and branch pipes for the outlet of products from the section are attached to the bottom of the body.
The beam frame is welded. The roof and bottom are attached to it through bearings. To the shaft (3) (pic 4.3) through the cheeks (4), weights are attached (5). To be able to change the radius of vibrations of the plansifter, a device for the distribution of weights is provided, consisting of a bracket (9) of couplings (12) and a pin 6. When divorcing weights, unscrew the bolt 8, clamping the cheeks to the shaft of that weight , which is not supported by the bolt 11 in the stop (10).
The balancing mechanism is driven by a belt drive from an electric motor. The belts are tensioned by moving the drive along the grooves of the plate using tensioning bolts. Changing the vibration frequency of the body is carried out by installing a replaceable pulley on the engine shaft. A pulley with a diameter of 145 mm is installed on the plansifter by the manufacturer, and a pulley with a diameter of 152 mm is supplied with a plansifter on request. The kinematic plansifter scheme is shown in Pic. 4.4.
Each panel is a welded structure made of rectangular tubes to which frame guides are attached. The different number of overlaps in the panels depends on the functional scheme. Sieve frames (Pic 4.5) with pallets are installed in the guide panels of each section. The partitions and guides of the panels form lateral by-pass channels. The sections are closed on both sides by doors 20 (Pic. 4.5). Removable boxes, the walls of which form bypass channels. Nozzles (feeders) are installed on the body roof 6.
Sieve frame 1 (Pic. 4.5.) is made of wooden blocks. The frame is divided into 4 cells by bars. Cleaners intended for cleaning sieves (3) are inserted in by 1 piece in cells before packing sieves at flour mills. The cleaner is a piece of cotton strap with a metal ball-head rivet inserted underneath. Sieve frames are made in two versions: single-pitch and double-pitch. In single-slope frames, the sieve passage is released only in one direction, into one side channel; in gable ones - in both directions.
The pallet is a sheet with curved ends on the short side and two corners attached from below, which serve to fix the pallet in the sieve body section, to remove the pallet with a frame from the section, and also to give it the necessary rigidity. To prevent mixing of separate fractions of the product, as well as for more free movement of the frames, pile fabric pads are glued on the corners of the pallet. Bike pads are glued between the frame and the pallet, as well as on the middle bars.
The pallet is a sheet with curved ends on the short side and two corners attached from below, which serve to fix the pallet in the sieve body section, to remove the pallet with a frame from the section, and also to give it the necessary rigidity. To prevent mixing of separate fractions of the product, as well as for more free movement of the frames, pile fabric pads are glued on the corners of the pallet. Bike pads are glued between the frame and the pallet, as well as on the middle bars.
The set of bypass boxes and walls installed in the doors correspond to certain functional diagrams. They serve to form streams of various product fractions resulting from screening on plansifter in the screening sections. (Pic. 4.9). The frames and walls of any door are interchangeable. In order to reduce the mass of the plansifter, most of the door parts, the frame are made of aluminum alloys. The feeders installed on the roof of the body serve to evenly distribute the original product onto 1, 2 or 3 sieve frames.
The receiving device is intended for feeding grain products into the plansifter body. It consists of a frame 1 (Pic. 4.6.), inlet nozzles 2 and nozzles 4. There are brackets with holes (holders) for fastening the receiver. Inlet pipes are designed for gravity connection. Floor nozzles (Pic. 4.7.) Consist of nozzle (1), box (3), plugs (2) and they re used to receive the sifting products from the plansifter.
The plansifter machine is driven by an AIR 112MV6UZ (АИР 112МВ6УЗ ) engine, power 4 kW, rotation speed 950 rpm. The electric motor must be powered from a three-phase alternating current network with a frequency of 50 ± 0.2 Hz and a voltage of 380 V. The electric plansifter circuit provides for turning on and off the motor, protecting the motor and electrical wiring from short-circuit currents, overload, and rated voltage. When the B2 button is pressed (Pic. 4.10.), the KM starter is triggered and self-blocked, which connects the motor to the power network with its contacts. The engine is stopped by pressing button B1.
The principle of operation of the plansifter is parallel and sequential sifting of the product through a set of flat horizontal sieves which are making a circular translational motion. The initial product from the receiving boxes enters the feeders, where is divided into three streams and directed to the sieve frames of the body, with the help of which the screening process takes place. The movement of the product inside the section is carried out according to one of the functional schemes. The product fractions are discharged from the body through the outlet pipes, enter the floor pipes, and then into the gravity of the flour mills.
Operating process. Before the plansifter breaks-in, remove the body frame guard from the side of the loading nozzles and dismantle the red-painted bracket that connects the balancer to the sieve transportation frame. It is strictly forbidden to start up the plansifter with the bracket still unremoved. Check the tightness of the doors. Check the absence of foreign objects, tools and devices on the plansifter and in the immediate vicinity of it.
During the plansifter breaks-in without products the following should be checked:
- direction of rotation of the balance bar, which should be clockwise when viewed from the top of the plansifter;
- absence of sharp noise and knocking, smooth vibration of the sieve body;
- condition of fastenings for ropes, fences, doors.
If any malfunctions are detected or the appearance of noise, knocking and vibration unusual for the plansifter operation, the plansifter should be stopped (turned off) immediately, the cause of the malfunctions should be identified, eliminated and the plansifter turned on again. The duration of the idling run, taking into account short-term stops for the inspection period, is approximately 24 hours. After running-in at idle speed, the plansifter is stopped, the temperature of the bearing housings is checked, which should not exceed 60˚C, then the tightening of threaded connections, the horizontal position of the body, the tension of each of the ropes are checked, after which the plansifter can be switched on to work with load products.
During the plansifter works special attention should be paid to the following:
- uniform loading of all sections;
- tightness of the body, dust emission at the joints is not allowed;
- no contamination of one fraction to another in another;
- condition of all vibrating assemblies and parts, noiseless operation;
- cleaning the sieves, checking the efficiency of the cleaners during the period when the plansifter is stopped;
- aspiration efficiency (for mills with mechanical transport).
The efficiency of separation processes and the coefficient of extraction of continuous fractions in the screening depends on the properties of the initial product, the load and the kinematic parameters of the screening - the frequency and radius of vibration of the body. Establishing the optimal kinematic sieving mode should aim to obtain the best technological effect.
The vibration radius of the body is determined as follows: a blank sheet of paper is glued to the free area of the roof of the body, and after reaching a steady state (10-20 minutes after launch), they touch the sheet with a sharpened pencil, motionlessly fixed in a special holder, or holding it motionless in an outstretched hand. The pencil leaves a trace on the paper - the plansifter oscillation trajectory close to a circle. The contact time of the pencil with the paper should correspond to one or two circles. Measure the largest D1 and the smallest D2 distance between two diametrically opposite points of the circle and determine the average radius R cf. according to the formula:
Rср = (D 1 + D) / 4
To measure the vibration frequency of the plansifter, it is necessary to bring any object in hand to contact with it. The number of strokes of the plansifter machine per minute is equal to the number of oscillations of the plansifter machine during the same time. Plansifter can operate at two frequencies: 3.7 s-1 (220 rpm) and 4 s-1 (240 rpm), depending on the pulley installed on the motor shaft.
Plansifter is supplied to the Consumer with a pulley with a calculated diameter of 145 mm, which corresponds to a body vibration frequency of 3.7 s-1. If it is necessary to re-equip any one or several sections from one functional diagram to another, the user of the plansifter can, on a separate order, receive the necessary sets of replacement parts and, by his own efforts and means, transfer the plansifter to the version he needs.
