Should the suction height of the stainless steel corrosion-resistant self-priming pump be included in the total head of the pump?

Due to the structural differences between self-priming pumps and centrifugal pumps, 

special attention must be paid during the selection process. 

Customers of self-priming pumps usually have certain requirements for the suction depth. 

So, do the lateral distance for self-priming and the vertical drop need to be recalculated 

and included in the total head of the pump?

The technical department of ATACH gave a direct conclusion: 

The suction depth of the self-priming pump is included in the total head of the pump, 

but their definitions and divisions are completely different and cannot be directly equated. 

The differences in key concepts

Clarify the differences between two core parameters:

1. What is "Total Head"?

The total head of a water pump refers to the total energy increment that a unit weight of 

liquid gains after passing through the pump. 

It can be expressed by the formula: H_total = H_suction_head + H_pressure_head + h_loss. 

It includes all the energy requirements for the liquid to overcome gravity, pipeline resistance, 

and height difference from the pump inlet to the outlet, and is a complete energy indicator.

2. What is "Suction Lift" ?

Suction lift (also known as allowable suction vacuum height) specifically refers to the maximum 

vertical height from the center of the pump shaft 

to the water level of the suction liquid that a self-priming pump can suck up. 

It is the core component of "suction head" and also a part of the total head. 

For example:

The nameplate of a self-priming pump indicates: total head 35 meters, suction head 5 meters.

This means: it can draw water from a position 5 meters below the pump shaft and then pump (pressurize) the 

water up to a height of 30 meters (35 meters total head - 5 meters suction head, 

and actual loss due to the pipeline must also be subtracted).