Dampeners pulsation type

Newman, C., and N. H. Moerke, Which Type of Pulsation Dampener Fits Your Compressor Problem Petroleum Processing. 1,724, Nov. (1955). 

The reciprocating action pump shown in Figure 9.23 is the most common type in use, and it delivers a constant flow. The pulsations that result can be removed or lessened by damping, but a better solution has been the use of two heads out of phase with one another, as shown in Figure 9.24. Sophisticated, computer-designed camshafts have been built to minimize the pulsations from these pumps, and additional dampening is usually not required. 

Components of CFA. All CFA techniques are similar in terms of components. All systems use some type of fluid pumping system, with peristaltic pumps the traditional choice. Piston-driven pumps have also been used however, the pulsations created by these pumps must be dampened. If such pulsation is allowed to occur, the flow patterns inside the tubing will not be reproducible and will affect the precision of the sample analysis. 

Type of pulse dampener Rest pulsation hydraulic RC 0.2% electronical n.d.a. optional n.d.a. pulseless pump n.d.a. pulseless pump pul seless pump Kopp-tube 1%... 

The GDV discussion is a particularly difficult one for pumps still having membrane-based pulsation dampeners. In this case, the GDV also depends on the system pressure, and by that on the separation flow rate [77]. While all major manufacturers of modern UHPLC pumps nowadays have established electronic control mechanisms in their high-end and most middle-class instruments that allow a virtually ripple-free flow delivery without dampeners, some older pumps or simpler entry-level models still have to rely on mechanical dampening. It would not be appropriate in general to use such pump types together with MS detection. 

Reciprocating compressors (for air supply to air-diy a plant of small capacity) these are to be procured when substantially constant low volumetric capacity is required at higher discharge pressures. Vendor may be asked to indicate the type of capacity control being provided (variable frequency drive or by aity other means) as well as pulsation suppression device for the discharge side. This may be in the form of dampening pots. 

Diaphragm, piston, and peristaltic pumps all deliver liquids in pulses. This uneven delivery can cause dosing problems when mixing is not sufflcient to ensure a rapid distribution of the chemical into the process water stream. Devices and systems are available to help smooth the delivery from these types of pumps. These devices are sometimes called pulsation dampeners (Figure 7-6). There are several designs. 

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