Gravity separator PSS is designed for separation of bulk (granular) materials with almost identical size, but with different weights.

Gravity separator PSS is designed for separation of bulk (granular) materials with almost identical size, but with different weights.

Gravity separator is produced in accordance with third category of GOST-15150, climate version “U” for internal market and export to temperate countries. However, machine has to work reliably in operating regimes at a temperature from 10 (°С) degrees below zero to 40 (°С) degrees above zero, relative moisture 80% with average annual temperature of 15 (°С) degrees above zero, atmospheric pressure from 650 to 800 mm Hg (86,6÷106,7 kPa).


Parameter title


Throughput (rated), kg/hour







Table oscillation frequency,

с-1 (oscillations /min)


Table oscillation range, mm


Slope of deck (table), deg

                                          longitudinal inclination

                                          transversal inclination



Impurities separation level, %


Air consumption, m3/min (m3/hour), max.


Rated power, kW


Dimensions, mm:







Weight, kg, max.


Structure and Functioning


Gravity separator consists of the following main parts (fig.2): frame 1, body 2, aspiration chamber 4, destoner 5, deck with metal wire mesh 3, feeder 7, adjusting valves 8. Loading nozzle 13 is fixed on the feeder. Air valve 9 with air consumption adjustment, unloading nozzles 11 and stones collecting bowl are fixed on the frame. Table and frame are connected through adjustment mechanisms of longitudinal inclination 14 and traversal inclination 15, which allow changing of table and deck slope respectively, in the range from 0 to 8 degrees in two planes.

Machine operates in accordance with the following technological process (fig.3):

Product, supplied to the machine through loading nozzle 13, is distributed along the inclined plane 6 by special valve, which prevents air suction to the machine from loading pipe. Deck, which performs longitudinal oscillatory movement along with table, is covered with metal wire mesh, which is blown up by the air stream. Air stream uniformity provides distribution device specified for this purpose. Product sorting is the result of operating plane vibration, air suction through nozzle (B) with throttle valve and double (longitudinal and transversal) slope.

Seeds processed in the machine are stratified as follows: heavy product is kept on the deck wire mesh and under the influence of longitudinal oscillations is removed to the outlet through the nozzle (F). Light particles float under the influence of air and move to the deck sides due to its transversal slope, and then unloaded through the side nozzles (C-D-E). Stones move in the opposite direction of the deck, towards horizontal valve with an adjustable opening. Horizontal valve allows creating of counterflow air circulation with adjustable speed. Such circulation ensures complete separation of grain from stones, which are discharged into the bowl located below (G). Air used in the stratification process, which contains dust and light product fractions, is purified in the cyclone or filter.