In the pharmaceutical laboratory, a variety of refrigeration equipment is used more, then as a more common equipment - pumps, mainly centrifugal pumps, volumetric pumps. Then, the user friend should have a better understanding of their performance, so that they can choose a more suitable pump.
In order to be able to select the type of pump that is suitable in the pharmaceutical laboratory, it is necessary to have a deep understanding of its performance and understand the difference between its specific working principle. To this end, we must understand that the centrifugal pump is dependent on the pressure (or The variable flow phenomenon of the indenter, while the positive displacement pump has a more or less constant flow phenomenon independent of the pressure.
The centrifugal pump and the volumetric pump are also different in viscosity. The centrifugal pump has a flow rate drop when the viscosity rises, and the volumetric pump actually has an increase in flow rate. This is because the higher viscosity liquid fills the voids in the volumetric pump, resulting in higher volumetric efficiency.
In the pharmaceutical laboratory, it is necessary to consider the influence of pressure on the equipment. After all, different pumps have different characteristics. Different efficiency, the pump will also increase the pressure. For the volumetric pump, as the pressure increases, Efficiency will actually increase, and centrifugal pumps have a better efficiency point. On both sides of this point, the overall pump efficiency will drop significantly.
The pharmaceutical laboratory has different conditions for the inlet of these two types of pumps. The centrifugal pump needs to reserve a certain amount of liquid in the pump to form a pressure difference. The liquid-free dry pump cannot be started by itself, due to the volume. The pump agitates the liquid by the expansion and contraction of the liquid volume, and the negative pressure is formed at the inlet, so the volumetric pump can initiate the perfusion. In some cases, this is the decision whether to choose the volumetric pump or the centrifugal pump. Elements.
The selection of different pumps in the pharmaceutical laboratory is to be selected according to their own needs. It takes a lot of time to make the right choices to achieve greater benefits.