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. 185-6131
Mfr. Part No.164.0148
BrandVerderflex
£131.97
Each
Units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 146-6434
Mfr. Part No.R4300342A
£182.89
Each
Units
Diaphragm Automatically Operated 3.7 g/min, 14 L/min - 3.1 bar 1/2 in Hose Barb 1/2 in Hose Barb - QUAD 4000 +54°C PP 24 V dc - Elastomer, Polypropylene (Housing)
RS Stock No. 185-6132
Mfr. Part No.164.0149
BrandVerderflex
£82.50
Each
Units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 185-6156
Mfr. Part No.169.6022
BrandVerderflex
£38.50
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 126-0254
Mfr. Part No.PA5120-F04
BrandSMC
£578.17
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6108
Mfr. Part No.162.1093
BrandVerderflex
£168.30
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6125
Mfr. Part No.164.0128
BrandVerderflex
£82.50
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6151
Mfr. Part No.169.6015
BrandVerderflex
£68.63
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6133
Mfr. Part No.164.0164
BrandVerderflex
£131.97
Each
Units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 185-6143
Mfr. Part No.164.0030
BrandVerderflex
£82.50
Each
Units
- - 375ml/min 86mm 1 bar - - - - - Nylon, Polycarbonate 24 V dc - -
RS Stock No. 185-6120
Mfr. Part No.163.0001
BrandVerderflex
£107.68
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6140
Mfr. Part No.164.0014
BrandVerderflex
£82.50
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6118
Mfr. Part No.162.1148
BrandVerderflex
£168.30
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6116
Mfr. Part No.162.1138
BrandVerderflex
£168.30
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 195-3558
Mfr. Part No.S1CBH04120PVTS070U111000EN
BrandProMinent
£2,727.40
Each
Units
Diaphragm - 117L/h 4m 4 bar - - IP65 S1cb - PVDF 100 → 230 V 220W PVDF
RS Stock No. 195-3560
Mfr. Part No.GXLAEU1020PVT20000U11130EN
BrandProMinent
£2,073.21
Each
Units
- - 20L/h 10m 10 bar - - - GXLa - PVDF 230 V 78W PVDF
RS Stock No. 179-7496
Mfr. Part No.PNDB1601PVT2000001
BrandProMinent
£525.04
Each
Units
- Air 1L/h - 16 bar - - - - - PVDF - - -
RS Stock No. 180-9203
Mfr. Part No.S1CBH07065PVTS070UA110S0EN
BrandProMinent
£2,494.58
Each
Units
Diaphragm Electric 65L/h - 7 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. 185-6112
Mfr. Part No.162.1123
BrandVerderflex
£168.30
Each
Units
- - - - - - - - - - - - - -
RS Stock No. 185-6109
Mfr. Part No.162.1098
BrandVerderflex
£269.21
Each
Units
- - - - - - - - - - - - - -
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