Pump inlet and outlet pipelines

Typically, to reduce pipeline losses, the pipe size must be larger than that of the pump’s inlet and outlet; therefore, many pumps require reducer fittings. Generally speaking, if the pump’s inlet is horizontal, it is best to use an eccentric reducer with the flat side facing upward, as this helps to remove air from the pipeline. In other cases, whether to use concentric or eccentric tubes depends on the installation requirements.

Simply put, it means \"supporting from above and below\"; for inlet pipelines, the bottom is leveled using an eccentric reducer at the upper part, while in the opposite case, the top is leveled.

The original poster mentioned it, which also reminded me. But I don’t know what the principle is. There are especially many reducer pipes right at the pump outlet.

For reducer fittings, it doesn’t matter if the standards for pumps differ from those of pipelines. When choosing pipelines for customers, I usually select them accordingly; some customers specify exactly what size of pipeline they need, saying that it was determined by the design institute and that they have no right to make changes. However, the inlet and outlet pipelines for the pumps produced by your company follow different standards. It is estimated that the pumps referred to by the design institute were not consistent. It’s not your pump, right? Please, pay up

As the pipe diameter increases and the flow velocity decreases, the pipeline resistance decreases, which is beneficial for fluid transportation.

When the pipe diameter is large and the flow velocity is low, the pipeline resistance is small. Restricted by the pump’s \"net positive suction head available\" (i.e., NPSHr), the pump’s inlet pipe is usually one to two sizes larger than the outlet pipe, in order to reduce the resistance along the inlet section. Thus, when connecting the inlet pipe to the pump’s suction inlet, an \"eccentric reducer\" is required; if the pump’s inlet is horizontal, the straight section of the eccentric reducer must be positioned at the lowest level. A \"concentric reducer\" is connected to the pump’s outlet to reduce the resistance in the output pipeline. As a result of such piping arrangements, since the diameters of the pipes are larger than those of the pump’s inlet and outlet, it will certainly increase the project costs. However, this is just a one-time investment. In production, as long as the pump is running, pipe resistance losses occur at all times. The greater these losses, the higher the current drawn by the motor, and consequently the higher the allowable cost. Therefore, users need to learn to view the issue of different pump diameters and pipe diameters in a dialectical manner. Getting stuck on reducing the pipe diameter can result in losses in operating costs of dozens or even over a hundred times.

When the pipe diameter is large and the flow velocity is low, the pipeline resistance is small. Restricted by the pump’s \"net positive suction head available\" (i.e., NPSHr), the pump’s inlet pipe is usually one to two sizes larger than the outlet pipe, in order to reduce the resistance along the inlet section. Thus, when connecting the inlet pipe to the pump’s suction inlet, an \"eccentric reducer\" is required; if the pump’s inlet is horizontal, the straight section of the eccentric reducer must be positioned at the lowest level. A \"concentric reducer\" is connected to the pump’s outlet to reduce the resistance in the output pipeline. As a result of such piping arrangements, since the diameters of the pipes are larger than those of the pump’s inlet and outlet, it will certainly increase the project costs. However, this is just a one-time investment. In production, as long as the pump is running, pipe resistance losses occur at all times. The greater these losses, the higher the current drawn by the motor, and consequently the higher the allowable cost. Therefore, users need to learn to view the issue of different pump diameters and pipe diameters in a dialectical manner. Getting stuck on reducing the pipe diameter can result in losses in operating costs of dozens or even over a hundred times.