Positive Displacement Pumps

Positive displacement pumps are speciality pumps that provide an approximate constant flow of fluid at the fixed speed. Pump trap a fixed amount of the fluid and then force it into a discharge pipe. Positive displacement pumps can produce the same flow at a given speed (RPM) no matter what the discharge pressure is. These type of pumps cannot operate against the closed valve because they have no shutoff head like centrifugal pumps. Positive displacement pumps constantly produce flow and the pressure built within the blocked line will damage the line, pump or both.

The positive displacement pumps can be divided into two main categories: reciprocating positive displacement pumps and rotary pumps.

Rotary pumps are very efficient because they can operate even with highly viscous fluids but require a slow steady speed rotation. If the mechanism rotation is too fast, the fluid can cause erosion, which eventually causes enlarged clearances that liquid can pass through and reduce pressure.

Rotary pumps can be divided into three main types:

  • Gear pumps: the simplest pump type that pumps liquid using 2 gears.
  • Screw pumps: more complicated pump type where the two screws are positioned against each other to pump the liquid.
  • Rotary vane pumps: these pumps have a cylindrical rotary engine. As the rotor circulates, vans trap fluid between the rotor and the engine housing, pushing the liquid through the pump.

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Description Price Pump Type Drive Type Maximum Flow Rate Maximum Head Maximum Working Pressure Input Connection Output Connection IP Rating Series Maximum Fluid Temperature Body Material Supply Voltage Input Power Wetted Materials
RS Stock No. 126-0253
Mfr. Part No.PA3210-F03
BrandSMC
HK$8,761.14
Each
units
- - - - - - - - - - - - - -
RS Stock No. 121-8587
Mfr. Part No.BT4B1604PVT2000U1110000
BrandProMinent
HK$10,335.15
Each
units
- Electric 3.6L/h - 16 bar 3/4 in G 3/4 in G IP65 BT4B +20°C PVDF 100 to 230 V 15.2 (Consumption)W PVDF
RS Stock No. 121-8590
Mfr. Part No.BT4B0220PVT2000U1110000
BrandProMinent
HK$10,302.17
Each
units
- Electric 19L/h - 2 bar 3/4 in G 3/4 in G IP65 BT4B +20°C PVDF 100 to 230 V 15.2 (Consumption)W PVDF
RS Stock No. 446-3506
Mfr. Part No.416990
HK$4,407.97
Each
units
Diaphragm Electric 10.8L/min 28m 15 bar 1/2 in NPT 1/2 in NPT IP44 AD550 +60°C - 230 V 33W -
RS Stock No. 185-6154
Mfr. Part No.169.6020
BrandVerderflex
HK$820.22
Each
units
- - - - - - - - - - - - - -
RS Stock No. 121-8593
Mfr. Part No.GMXa0414PVT20000U11130EN
BrandProMinent
HK$14,606.02
Each
units
- Electric 14L/h - 4 bar 3/4 in G 3/4 in G IP65 GMXa +20°C PVDF 100 to 230 V 24 / 30 (Consumption)W PVDF
RS Stock No. 121-8592
Mfr. Part No.GMXa0708PVT20000U11130EN
BrandProMinent
HK$14,953.71
Each
units
- Electric 7.6L/h - 7 bar 3/4 in G 3/4 in G IP65 GMXa +20°C PVDF 100 to 230 V 24 / 30 (Consumption)W PVDF
RS Stock No. 185-6156
Mfr. Part No.169.6022
BrandVerderflex
HK$820.22
Each
units
- - - - - - - - - - - - - -
RS Stock No. 667-9104
Mfr. Part No.D3135H7011AR
HK$1,833.31
Each
units
Diaphragm Electric 8.1L/min 30m 7.1 bar 3/8 in NPT 3/8 in NPT IP44 D3135 - Glass Fibre Reinforced PP 12 V - -
RS Stock No. 705-9374
Mfr. Part No.53020-2013
HK$4,302.03
Each
units
Centrifugal Electric 18L/min 15m 1.7 bar 3/4 in BSP 3/4 in BSP IP54 - - Bronze 230 V 180W -
RS Stock No. 705-9355
Mfr. Part No.R3521139A
HK$1,961.44
Each
units
Diaphragm Electric 15.1L/min 41m 4.1 bar 1/2 in Hose Barb 1/2 in Hose Barb IP54 R352 +60°C PP 12 V 108W -
RS Stock No. 125-4049
Mfr. Part No.148.1021
BrandVerderflex
HK$22,367.54
Each
units
Peristaltic Electric 1310ml/min - - 8 mm Tube - - Vantage 3000 - - 85 → 265 V ac - -
RS Stock No. 185-6136
Mfr. Part No.164.0166
BrandVerderflex
HK$1,577.30
Each
units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 185-6158
Mfr. Part No.169.6023
BrandVerderflex
HK$820.22
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6145
Mfr. Part No.164.0032
BrandVerderflex
HK$1,577.30
Each
units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 122-6646
Mfr. Part No.T530-ANB-D
BrandTecnomatic
HK$44,725.09
Each
units
Diaphragm Air 530L/min 8.5m - - 2 in Plain - T530 - Aluminium - - Aluminium Body, NBR Diaphragms, NBR Valve Balls
RS Stock No. 185-6114
Mfr. Part No.162.1128
BrandVerderflex
HK$3,217.62
Each
units
- - - - - - - - - - - - - -
RS Stock No. 125-4041
Mfr. Part No.AU R1580240 05
BrandVerderflex
HK$4,633.99
Each
units
Peristaltic Electric 2200ml/min - - - - - M1500 - ABS 24 V dc 30W -
RS Stock No. 705-6669
Mfr. Part No.AU UV EZ
BrandVerderflex
HK$17,166.41
Each
units
Peristaltic Electric 0.937L/min 10m 1 bar - - IP40 UV-EZ +40°C Polyamide 100 → 120 V, 220 → 240 V 100VA -
RS Stock No. 185-6149
Mfr. Part No.164.0049
BrandVerderflex
HK$1,577.30
Each
units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -