API674 is a specification issued by the American Petroleum Institute that gives guidance concerning the safe installation of reciprocating pumps and associated equipment, such as pulsation dampeners. The guidance it provides is conservative in nature and is widely considered, if followed correctly, to provide systems with safe levels of pressure pulsation and piping vibration due mechanical resonances.
Both a gas charged unit and liquid filled unit work in the same way, in that the compressibility of the fluid, or gas, inside the unit is used to absorb the energy of the pulsation coming from the pump. However, because a gas is obviously more compressible than a liquid, units that are gas charged are usually smaller than equivalent liquid filled units. Gas charged units will often need to be re-charged during routine maintenance, whilst liquid filled units do not require any maintenance.
You always need an amount of pressure drop otherwise your system will simply not flow. Even in straight pipes there is always a pressure difference between the inlet and outlet.
Our liquid filled pulsation dampeners can be fitted horizontally, vertically, or however you wish. Inlet and outlet nozzles can have almost any orientation you require to match you piping.
Residual pulsation level is a general term referring to the pulsation level after the fitment of a pulsation dampener and is calculated with respect to the original un-dampened calculated pulsation level. Experience has shown that a residual pulsation level of +/-3% will generally give a smooth running system, however, many installation are now provided on the basis of a more conservative +/-1.5%. Where API674 is considered the residual pulsation levels will often be below +/-0.5%.
Our maintenance free dampeners have no maintenance requirements other than a periodic inspection.
Unlike our standard suction stabiliser the vapour dome type of suction stabiliser does not need a supply of gas as it simply vaporises the process fluid. As the vapour pocket is self regulating it will automatically adjust itself if the pumping conditions change, or if there is a quantity of entrained gas in the liquid, unlike our standard unit which will require either automatic, or manual adjustment.