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:
A. 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. 705-6669
Mfr. Part No.AU UV EZ
BrandVerderflex
HK$16,108.66
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. 185-6154
Mfr. Part No.169.6020
BrandVerderflex
HK$773.34
Each
units
- - - - - - - - - - - - - -
RS Stock No. 705-9359
Mfr. Part No.R3521339A
HK$1,972.03
Each
units
Diaphragm Electric 7.6L/min 41m 4.1 bar 3/4 in NPT 3/8 in NPT - R352 +60°C PP 24 V 144W -
RS Stock No. 122-6646
Mfr. Part No.T530-ANB-D
BrandTecnomatic
HK$42,168.45
Each
units
Diaphragm Air 530L/min 8.5m - - 2 in Plain - T530 - Aluminium - - Aluminium Body, NBR Diaphragms, NBR Valve Balls
RS Stock No. 180-9202
Mfr. Part No.S1CBH12035PVTS070UA110S0EN
BrandProMinent
HK$29,194.19
Each
units
Diaphragm Electric 42L/h - 10 bar, 12 (SST) bar DN 10 1-3/4 in G IP55, IP65 S1Cb +100 °C @ 15 min (2 bar) PVDF 100 → 230 V ac - PVDF
RS Stock No. 185-6152
Mfr. Part No.169.6016
BrandVerderflex
HK$773.34
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6158
Mfr. Part No.169.6023
BrandVerderflex
HK$773.34
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6111
Mfr. Part No.162.1113
BrandVerderflex
HK$3,033.69
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6128
Mfr. Part No.164.0131
BrandVerderflex
HK$1,487.13
Each
units
- - - - - - - - - - - - - -
New
RS Stock No. 195-3562
Mfr. Part No.DFXAEU0730SPTU0000U11130EN
BrandProMinent
HK$23,326.16
Each
units
Peristaltic - 30L/h 6m 7 bar - - - DFXA - PVDF 100 → 230 V 45W TPV
RS Stock No. 121-8591
Mfr. Part No.GMXa1602PVT20000U11130EN
BrandProMinent
HK$13,660.98
Each
units
- Electric 2.3L/h - 16 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. 705-9352
Mfr. Part No.R3811242A
HK$2,368.77
Each
units
Diaphragm Electric 5.5L/min 105m 10.5 bar 3/8 in NPT 3/8 in NPT - R381 +60°C Glass Fibre Reinforced Nylon 230 V - -
RS Stock No. 185-6145
Mfr. Part No.164.0032
BrandVerderflex
HK$1,487.13
Each
units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 667-9113
Mfr. Part No.G573215A
HK$2,702.47
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. 121-8596
Mfr. Part No.DLTA1020PVT2000U11131EN0
BrandProMinent
HK$14,308.01
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. 180-9205
Mfr. Part No.DCCAW006PR0010EN
BrandProMinent
HK$6,053.10
Each
units
- - 80L/h - - - - IP67 DCCA - - 90 → 253 V ac - -
RS Stock No. 667-9100
Mfr. Part No.D3131H5011AR
HK$1,624.48
Each
units
Diaphragm Electric 5.3L/min 30m 4.2 bar 3/8 in NPT 3/8 in NPT IP44 D3131 +54°C Glass Filled PP 12 V dc - -
RS Stock No. 125-4041
Mfr. Part No.AU R1580240 05
BrandVerderflex
HK$4,369.10
Each
units
Peristaltic Electric 2200ml/min - - - - - M1500 - ABS 24 V dc 30W -
RS Stock No. 185-6138
Mfr. Part No.164.0012
BrandVerderflex
HK$1,487.13
Each
units
- - - - - - - - - - - - - -
RS Stock No. 185-6153
Mfr. Part No.169.6017
BrandVerderflex
HK$773.34
Each
units
- - - - - - - - - - - - - -
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