The positive displacement gear pumps are designed for pumping of petroleum products without mechanical impurities, such as oils, black oil, petroleum, at temperatures below 70°C and diesel fuel at temperatures up to 40°C, and also of easily solidifying liquids, such as paraffin and others, that have greasing capacity.
They are applied in systems of fuel and petroleum products conveyance, and also for feeding fuel oil to boiler installations.
- NMSHF 0,6-25-0,63/25ju-1
- NMSH - pump type (gear)
- F - pump and motor are mounted on the connecting piece
- 0,6 - flow (liters per 100 rotation
- 25 - maximum pressure the pump ensures (kgf/cm2)
- 0,63 - pumping unit flow (m3h)
- 25 - pumping unit working pressure (kgf/cm2)
- ju - fluid end of pump material designation
- 1 - motor modification
- Rp - flow adjustability
The delivery of the working liquid in the positive displacement gear pumps is carried out with the help of gears installed on the driving and driven shafts that are connected to the electric motor by a coupling. The pumps are complete with safety valves that prevent the excess of pressure in the pipeline above the permissible value.
The working body in these pumps is gears. As gears rotate, vacuum is created in the suction side and the liquid under suction pressure fills in the spaces between the gear teeth. Moving under pressure to where the teeth of one gear enter the hollows between the teeth of another, the pumped liquid is expelled into the pumping stub tube.
The pumps are manufactured with differences in the materials used in their hydraulic parts: of cast iron SCh20 - without a marking, of bronze - with the "B" marking.
The flow part is made of cast-iron, bronze or aluminum. The rotor is made, as a rule, of steel 18HGT.
The pumping units are complete with electric motors of various power and types (explosion-proof) depending on the kind and viscosity of the pumped liquid and on the operating conditions.
The admissible vacuum lift, at the pumped liquid viscosity of 0,75 cm2/c, is about 5m.
Units, such as SHG, are designed for metering out of bitumen, and other similar liquids, with temperatures up to 190°C. The design provides heating.