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. 195-3561
Mfr. Part No.GXLAEU0730PVT20000U11130EN
BrandProMinent
HK$25,274.90
Each
units
- - 30L/h 7m 7 bar - - - GXLa - PVDF 230 V 78W PVDF
RS Stock No. 195-3558
Mfr. Part No.S1CBH04120PVTS070U111000EN
BrandProMinent
HK$33,250.25
Each
units
Diaphragm - 117L/h 4m 4 bar - - IP65 S1cb - PVDF 100 → 230 V 220W PVDF
RS Stock No. 126-0251
Mfr. Part No.PA3120-F03
BrandSMC
HK$5,173.35
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6153
Mfr. Part No.169.6017
BrandVerderflex
HK$820.22
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6146
Mfr. Part No.164.0047
BrandVerderflex
HK$1,577.30
Each
units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 179-7497
Mfr. Part No.PNDB0708PVT2000001
BrandProMinent
HK$6,679.30
Each
units
- Air 6.3L/h - 7 bar - - - - - PVDF - - -
RS Stock No. 185-6112
Mfr. Part No.162.1123
BrandVerderflex
HK$3,217.62
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6117
Mfr. Part No.162.1143
BrandVerderflex
HK$3,217.62
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6108
Mfr. Part No.162.1093
BrandVerderflex
HK$3,217.62
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6152
Mfr. Part No.169.6016
BrandVerderflex
HK$820.22
Each
units
- - - - - - - - - - - - - -
RS Stock No. 179-7496
Mfr. Part No.PNDB1601PVT2000001
BrandProMinent
HK$6,400.86
Each
units
- Air 1L/h - 16 bar - - - - - PVDF - - -
RS Stock No. 125-4040
Mfr. Part No.AU R1560240 01
BrandVerderflex
HK$4,633.99
Each
units
Peristaltic Electric 1300ml/min - - - - - M1500 - ABS 24 V dc 30W -
RS Stock No. 121-8596
Mfr. Part No.DLTA1020PVT2000U11131EN0
BrandProMinent
HK$24,586.70
Each
units
- Electric 19.1L/h - 10 bar 3/4 in G 3/4 in G IP65 DLTa +20°C PVDF 100 to 230 V 78 (Consumption)W PVDF
RS Stock No. 125-4038
Mfr. Part No.AU R1560125 01
BrandVerderflex
HK$4,633.99
Each
units
Peristaltic Electric 800ml/min - - - - - M1500 - ABS 24 V dc 30W -
RS Stock No. 667-9113
Mfr. Part No.G573215A
HK$2,879.92
Each
units
Diaphragm Air 19L/min - 6.9 bar 1/2 in Hose Barb, 1/4 in Hose Barb 1/2 in Hose Barb, 1/4 in Hose Barb - G5732 +48.9°C PP - - Hastelloy C, Kalrez, PP, Santoprene, Viton
RS Stock No. 195-3557
Mfr. Part No.S1CBH07065PVTS070U111000EN
BrandProMinent
HK$32,002.00
Each
units
Diaphragm - 63L/h 7m 7 bar - - IP65 S1cb - PVDF 100 → 230 V 220W PVDF
RS Stock No. 125-4046
Mfr. Part No.AU M310240 12
BrandVerderflex
HK$6,681.99
Each
units
Peristaltic Electric 3400ml/min - - - - - R3DC - Aluminium 24 V 100W -
RS Stock No. 185-6140
Mfr. Part No.164.0014
BrandVerderflex
HK$1,577.30
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6120
Mfr. Part No.163.0001
BrandVerderflex
HK$1,287.02
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6119
Mfr. Part No.162.1118
BrandVerderflex
HK$3,753.79
Each
units
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