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. 705-6687
Mfr. Part No.AU R2550015 RS1
BrandVerderflex
HK$1,882.09
Each
units
Peristaltic Electric 0.03L/min 10m 1 bar - - - R2550 +40°C ABS, PC 12 V dc 6VA -
RS Stock No. 705-6671
Mfr. Part No.AU R2550120 RS1
BrandVerderflex
HK$1,845.50
Each
units
Peristaltic Electric 0.24L/min 10m 1 bar - - - R2550 +40°C ABS, PC 12 V dc 6VA -
RS Stock No. 705-6659
Mfr. Part No.AU ES3R16
BrandVerderflex
HK$1,118.37
Each
units
Peristaltic Electric - 20m 1 bar - - - ES3R1 +40°C Polyamide - 20W -
RS Stock No. 705-6656
Mfr. Part No.AU EZ3R16
BrandVerderflex
HK$1,118.37
Each
units
Peristaltic Electric - 20m 1 bar - - - EZ3R1 +40°C Polyamide - 20W -
RS Stock No. 702-6894
BrandRS PRO
HK$481.34
Each
units
Diaphragm Electric 150ml/min - 1 bar - - IP50 D200 +100°C Nylon 1.5 → 4.5 V 0.48W Nitrile, Nylon, Silicone
RS Stock No. 705-9321
Mfr. Part No.RLFP122202D
HK$847.25
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. 705-6675
Mfr. Part No.AU R2550060 RS1
BrandVerderflex
HK$1,854.28
Each
units
Peristaltic Electric 0.12L/min 10m 1 bar - - - R2550 +40°C ABS, PC 12 V dc 6VA -
RS Stock No. 667-9194
Mfr. Part No.TEP50PTWD
BrandTecnomatic
HK$7,603.51
Each
units
Diaphragm Air 53L/min 70m - 1/2 in G 1/2 in G - TE53-PTW - PP - - -
RS Stock No. 705-6678
Mfr. Part No.AU EV EZ
BrandVerderflex
HK$12,121.37
Each
units
Peristaltic Electric 0.6L/min 20m 1 bar - - IP40 EV-EZ +40°C Polyamide 100 → 120 V, 220 → 240 V 100VA -
RS Stock No. 702-6898
BrandRS PRO
HK$637.47
Each
units
Diaphragm Electric 380ml/min - 11 psi - - IP50 D250 +100°C Aluminium 1.5 → 5 V 0.48W Anodized Aluminium, Nitrile, Silicone, Stainless Steel
RS Stock No. 121-8598
Mfr. Part No.DF2A0208P00A10W1
BrandProMinent
HK$3,104.50
Each
units
Peristaltic Electric 0.8L/h - 1.5 bar - - IP65 DF2a +20°C - 230 V 5 (Consumption)W -
RS Stock No. 705-9333
Mfr. Part No.R3711132A
HK$1,472.09
Each
units
Diaphragm Electric 5.5L/min 69m 6.9 bar 3/8 in BSP 3/8 in BSP - R371 +60°C Glass Fibre Reinforced Nylon 12 V dc 108W -
RS Stock No. 667-9182
Mfr. Part No.TEP130-PX
BrandTecnomatic
HK$9,150.63
Each
units
Diaphragm Air 132L/min 80m - 1 in Push Fit 1 in Push Fit - TEP132 - PP - - -
RS Stock No. 705-9327
Mfr. Part No.RLF222201D
HK$1,027.38
Each
units
Diaphragm Electric 3.8L/min 21m 2.5 bar 3/8 in Hose Barb 3/8 in Hose Barb - RLF222 +43°C PP 24 V dc 30W -
RS Stock No. 446-3483
Mfr. Part No.416989
HK$3,185.33
Each
units
Diaphragm Electric 3L/min 89m 20 bar - - IP44 AD4/90 +77°C - 230 V 55W -
RS Stock No. 619-4432
Mfr. Part No.156993
BrandBurkert
HK$1,933.36
Each
units
Diaphragm Electric 5ml/min - 200 mbar - - IP40 7604 +60°C PEEK 24 V dc 1.5W FFKM, PEEK
RS Stock No. 144-844
Mfr. Part No.BL 5/D
HK$1,893.82
Each
units
Diaphragm Electric 5L/h - 101.5 psi - - IP65 BL5/D - Glass Fibre Reinforced PP 220 V, 240 V 200W -
RS Stock No. 667-9097
Mfr. Part No.R4300242A
HK$2,588.19
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. 705-6665
Mfr. Part No.AU EZ3R16 060 02
BrandVerderflex
HK$3,110.08
Each
units
Peristaltic Electric 0.225L/min 20m 1 bar - - - EZ3R1 +40°C Polyamide 12 V dc 17W -
RS Stock No. 144-850
Mfr. Part No.BL 10/D
HK$1,944.03
Each
units
Diaphragm Electric 10.8L/h - 43.5 psi - - IP65 BL10/D - Glass Fibre Reinforced PP 220 V, 240 V 200W -
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