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. 705-9393
Mfr. Part No.53081-2003-230
£617.55
Each
Units
Centrifugal Electric 80L/min 20m - 1-1/2 in BSP 1-1/2 in BSP IP55 - - Bronze 230 V ac 550W -
RS Stock No. 667-9097
Mfr. Part No.R4300242A
£230.76
Each
Units
Diaphragm Electric 12L/min 40m 2.1 bar 1/2 in Hose Barb 1/2 in Hose Barb IP44 R4300 +54°C Glass Fibre Reinforced PP 230 V ac - -
RS Stock No. 667-9113
Mfr. Part No.G573215A
£240.95
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. 705-6675
Mfr. Part No.AU R2550060 RS1
BrandVerderflex
£164.55
Each
Units
Peristaltic Electric 0.12L/min 10m 1 bar - - - R2550 +40°C ABS, PC 12 V dc 6VA -
RS Stock No. 705-6653
Mfr. Part No.AU EZ3R16 150 02
BrandVerderflex
£273.20
Each
Units
Peristaltic Electric 0.562L/min 20m 1 bar - - - EZ3R1 +40°C Polyamide 12 V dc 20W -
RS Stock No. 705-9352
Mfr. Part No.R3811242A
£211.20
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. 121-8587
Mfr. Part No.BT4B1604PVT2000U1110000
BrandProMinent
£834.66
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. 122-6642
Mfr. Part No.TEP130-ANB-D
BrandTecnomatic
£878.77
Each
Units
Diaphragm Air 130L/min 8.5m - 1 in Plain 1 in Plain - TEP130 - Aluminium - - Aluminium Body, NBR Diaphragms, NBR Valve Balls
RS Stock No. 667-9182
Mfr. Part No.TEP130-PX
BrandTecnomatic
£815.88
Each
Units
Diaphragm Air 132L/min 80m - 1 in Push Fit 1 in Push Fit - TEP132 - PP - - -
RS Stock No. 667-9100
Mfr. Part No.D3131H5011AR
£144.84
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. 667-9093
Mfr. Part No.R4300143A
£177.89
Each
Units
Diaphragm Electric 19L/min - 3.1 bar 3/4 in Hose Barb 3/4 in Hose Barb IP44 R4300 - PP 12 V dc - Buna, Elastomer, PP
RS Stock No. 705-9324
Mfr. Part No.RLFP122201D
£85.97
Each
Units
Diaphragm Electric 3.8L/min 21m 2.5 bar 3/8 in Hose Barb 3/8 in Hose Barb - RLF122 +43°C PP 12 V dc 30W EPDM, PP, Santoprene, Stainless Steel, Viton
RS Stock No. 122-6646
Mfr. Part No.T530-ANB-D
BrandTecnomatic
£3,742.01
Each
Units
Diaphragm Air 530L/min 8.5m - - 2 in Plain - T530 - Aluminium - - Aluminium Body, NBR Diaphragms, NBR Valve Balls
RS Stock No. 705-9374
Mfr. Part No.53020-2013
£359.94
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. 705-6665
Mfr. Part No.AU EZ3R16 060 02
BrandVerderflex
£277.30
Each
Units
Peristaltic Electric 0.225L/min 20m 1 bar - - - EZ3R1 +40°C Polyamide 12 V dc 17W -
RS Stock No. 705-6662
Mfr. Part No.AU EZ3R16 100 02
BrandVerderflex
£273.20
Each
Units
Peristaltic Electric 0.375L/min 20m 1 bar - - - EZ3R1 +40°C Polyamide 12 V dc 17W -
RS Stock No. 144-866
Mfr. Part No.BL 15/D
£169.13
Each
Units
Diaphragm Electric 15.2L/h - 14.5 psi - - IP65 BL15/D - Glass Fibre Reinforced PP 220 V, 240 V 200W -
RS Stock No. 705-6684
Mfr. Part No.AU R2550030 RS1
BrandVerderflex
£167.01
Each
Units
Peristaltic Electric 0.06L/min 10m 1 bar - - - R2550 +40°C ABS, PC 12 V dc 6W -
RS Stock No. 121-8600
Mfr. Part No.DF2A0224P00A10W1
BrandProMinent
£332.29
Each
Units
Peristaltic Electric 2.4L/h - 1.5 bar - - IP65 DF2a +20°C - 230 V 5 (Consumption)W -
RS Stock No. 667-9107
Mfr. Part No.CW474-024
BrandXylem
£250.45
Each
Units
Diaphragm Electric 13L/min - 3 bar 1/2 in Hose Barb 1/2 in Hose Barb IP55 CW474 - Glass Fibre Reinforced PP 230 V ac 120W -