How many millimeters is the diameter of the water outlet of the four inch pump?
This question is of no practical significance. The user does not care about this figure. The concern should be the nominal diameter, which is fitted with flanges and pipes. Moreover, the pump shell is cast iron, the inside diameter is not processed, and there is no matching parts, there is only one manufacturing size.
Here is a 4 inch inch, not rural, 1 inches =25.4 mm, 4 inches is approximately 100mm, with DN100 pipeline.
If it is a centrifugal pump, the nominal diameter of the outlet is less than 4 inches, there is a conical short tube to enlarge the standard 4 inch outlet flange, from here, is the standard 4 inch flange connection.
