They are designed to transport sludge (slimes) resulting from processing of ore or other non-metallic minerals, sand and other abrasives. The solid particles contained in the sludge (hydraulic mixture) must not be larger than 6 mm and the density of the mixture must not be greater than 2,200 kg/m3.
The pumps are manufactured in 6 sizes: ПГ 60/20, ПГ 160/32, ПР 250/28, ПР 400/35, ПР 800/31.5 and ПР 1 250/31.5. The first digit (e.g., 400) shows productivity in m3/hr, and the second one (e.g. 35) shows the pressure in meters of water column.
These pumps are centrifugal, single-stage, with central (axial) suction. The shaft is horizontal. Bearing is implemented in a separate bearing housing with roller bearings. The structure allows for lubrication both with oil and grease. All parts in contact with the abrasive hydraulic mixture are coated with a special wear-resistant rubber mixture. These parts naturally wear out more quickly and in order to facilitate their removal, the pump body is divided vertically into two halves. The pump may be mounted directly on a substructure or by a movable frame. The frame allows for comfortable operation when replacing wearing parts.
For ensuring best pump performance, the gap between the top of the impeller and the opposite wall of the housing is essential. Therefore, this gab is easily and fast adjusted by an adjusting bolt that axially shifts the bearing housing.
The shaft seal on the side of the pump housing is a packing gland. In order to avoid penetrating of abrasion mixture from the pump to the gasket, clean flushing water is supplied to the gasket. The pressure and the inlet of the gasket must be twice as much as that of the pump. It is recommended to fix a pressure gauge for water pressure control. Furthermore, it is desirable to mount a locking device to turn off the pump when no flushing water is fed. Please, note, that after each pump deactivation, flushing water should be allowed to run for several minutes after the deactivation of the pump.
The drive motor is placed on a platform above the pump. This saves a lot of installation space. The transmission of torque from the motor to the pump shaft is performed through V-belts. Their tension is convenient and simple – by lifting the platform.
The V-belt transmission allows by using V-belt pulleys of suitable diameter to accurately select the speed of the pump depending on the intended use.
Pumps of the ПР type can also operate by suction from a certain depth depending on the density of the hydraulic mixture; however, it may create cavitation. In order to avoid cavitation, it is recommended that the pump should operate submerged, i.e. to draw water from a tank placed at the level of the pump.
The design of the pump allows for connection with the irrigation conduit and at an angle of 0 to 180 degrees in intervals of 45 degrees. The pumps are delivered with flexible connections for connecting to the suction and discharge piping. They avoid the transmission of vibrations from the pump to the piping which may result in damages. If two or three pumps are connected in series in order to obtain a greater feeding height, pimps with reinforced housings should be used..
|№||TECHNICAL DATA||PR 60/20||PR
|1.||Performance, m3/h||60||160||320||250||400||800||1 250|
|2.||Pressure, m H2O||20||32||22||28||35||31.5||31.5|
|3.||Operating wheel diameter, mm||265||355||460||536||536||640||660|
|4.||Rotational speed of the operating wheel, min -1||1 460||1 460||980||800||900||730||710|
|5.||Passage section between blades, mm||24||30||55||88||88||100||139|
|6.||Electric motor, power, kW||10||22||45||55||132||160||250|
|7.||Pressure flange diameter, mm||75||100||150||200||200||250||300|
|8.||Suction flange diameter, mm||100||125||200||254||254||300||3509|
|9.||Overall dimensions, mm|
|– length||1 200||1 300||1 550||1 700||1 700||2 345||1 930|
|– width||600||900||1 240||1 523||1 523||1 340||2 400|
|– height||1 090||1 250||1 650||1 865||1 895||1 635||1 410|
|10.||Weight, kg||396||445||2 070||2 320||2 623||4 100||5 120|