What piping arrangement is also known as the balancing pipe?

The balancing pipe, often referred to as an equalizing line, is an important component in steam systems. Its primary function is to ensure that pressure is balanced between different sections of the piping, allowing for uniform steam distribution and efficient energy transfer. By equalizing the pressure, it helps to prevent issues such as steam trapping or uneven flow that can lead to system inefficiencies.

In contrast, a condensate return line is primarily used to carry condensate back to a boiler or other part of the system rather than balancing pressure. A steam trap functions to automatically discharge condensate and non-condensable gases from steam systems while preventing steam from escaping, which does not serve the same purpose as balancing. Lastly, a blow-off line is intended for the removal of unwanted materials or fluids, often as part of a maintenance routine, rather than for balancing pressures in a steam system.

Thus, the term "equalizing line" accurately describes the function associated with a balancing pipe, making it the correct choice.