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WellChrom Pneumatic Pump K-1900

The high performance WellChrom Pneumatic Pump K-1900 has been designed for solvent delivery in process chemistry, column packing or preparative chromatography. This pump is powered by compressed air. Since no electrical connection is required, the WellChrom Pneumatic Pump K-1900 is suitable for operation in explosion proof environments. This particular device has been developed for constant pressure applications. The main application field is the packing of high performance columns (microbore, analytical, and preparative) of up to 1,000 bar. A cooling device (heat exchanger) to be mounted on the pump head is available. It allows to operate with supercritical fluids such as CO2. The flow of the pump is highly reproducible and only little maintenance efforts are required.

The Pneumatic Pump K-1900 can be configured with four different pump heads (double piston design) to fulfil the most pressure and flow rate requirements. These pump heads are easy to maintain and compatible with our Preparative HPLC Pump K-1800 as well. Pump heads can easily be changed by loosening only four screws. Experienced users can disassemble the heads for validation or simple maintenance tasks like cleaning, changing piston seals, etc. The delivery volume depends on the required air pressure and the loss of pressure along the column or any device that generates back pressure. You can reach the maximum delivery volume at minimum eluent pressure (below 1 bar). The minimum flow rate (ca. 5 ml/min) is achieved at the maximum eluent pressure.

WellChrom Pneumatic Pump K-1900

Technical Data and Ordering Information The figures 1 to 3 show the delivery volume as a function of the eluent pressure for available pump heads. In those figures you can see the limitation values for liquid pressure and flow rate according to ’’Technical data of individual pump heads’’ and the maximum allowed air pressure for each pump head. With constant air pressure the flow rate increases, if the liquid pressure decreases. The diagrams show the reachable flow rates and eluent pressures ∆p for different columns (marked by a ▲, ■ or ●) with different hydraulic resistants.

Technical Data of Pneumatic Pump K-1900 Required air pressure Minimum 1 bar, maximum* 7 bar Dimensions 220 x 185 x 340 mm (WxHxD) Weight 10.2 kg

Technical data of individual pump heads Required Compressed Air 1200 Liquid Pressure [bar]

4,2 bar

100 ml

4 bar 800 3 bar 2 bar


1 bar 0 0




Flow Rate [ml/min] 900 Liquid Pressure [bar]

Required Compressed Air 600

6 bar


5 bar 4 bar 3 bar


250 ml

7 bar

2 bar 1 bar 300



Flow Rate [ml/min]

Required compressed air

1000 ml

Liquid Pressure [bar]

7 bar 6 bar 5 bar

3 bar 2 bar 1 bar

0 0




1,000 4.2* 9.5 6.35 0.6 1:250

670 7 9.5 9.525 1.35 1:96

250 7 9.5 14.29 3.05 1:47

160 7 9.5 19.05 5.4 1:23

Order No. WellChrom Pneumatic Pump K-1900 Pneumatic Pump K-1900 with 100 ml pump head Pneumatic Pump K-1900 with 250 ml pump head Pneumatic Pump K-1900 with 500 ml pump head Pneumatic Pump K-1900 with 1,000 ml pump head

Order No. Pump heads and cooling devices

4 bar



Using the 100 ml pump head, the external air pressure should never exceed 4.2 bar. Otherwise the pump head and mechanics can be damaged.

A40289 A40281 A40283 A40282



100 ml 250 ml 500 ml 1,000 ml

Ordering Information

0 0

Characteristics Pump Head Type Maximum Flow Rate (ml/min) at Minimum Back Pressure Maximum Back Pressure (bar) for Solvent Delivery Maximum Allowed Air Pressure (bar) Piston Stroke (mm) Piston Diameter (mm) Piston Stroke Volume per Cycle (ml) Pneumatic Transformation Ratio




Flow Rate [ml/min]

A4029 A4021 A4038 A4022 A2034

100 ml pump head, including accessory kit 250 ml pump head, including accessory kit 500 ml pump head, including accessory kit 1,000 ml pump head, including accessory kit Cooling device, suitable for all pump heads

Visit for details on complete HPLC systems, HPLC columns, and osmometers. Advanced Scientific Instruments Wissenschaftliche Gerätebau Dr. Ing. Herbert Knauer GmbH Hegauer Weg 38, 14163 Berlin, Germany Telephone: +49 (0)30 / 80 97 27-0 Telefax: +49 (0)30 / 8 01 50 10 E-Mail: Internet:

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