Hume Pipes

In Hume pipe notation, NP stands for "Non-Pressure." This means that Hume pipes are not designed to be used under pressure, like water supply or gas supply pipes. 

Hume pipes are typically used for gravity flow applications for draining water or sewage in both agricultural and industrial applications. NP Hume pipes are designed to withstand external loads such as soil and traffic loads but not internal pressure. 

The NP classification of Hume pipe is a way of categorizing them based on the pipe's strength, which is determined by the thickness of the walls and the reinforcement provided. The higher the NP grade, the thicker the walls, and the more reinforcement the pipe has, resulting in increased strength and load-bearing capacity.

Hume pipes are reinforced concrete pipes used for water drainage and sewage systems. The strength of the Hume pipe is determined by the class of the pipe, and NP2 and NP3 are both classes of Hume pipes. 

NP3 class Hume pipes are generally stronger than NP2 class Hume pipes. NP2 pipes are usually used for low to medium traffic loads, while NP3 pipes are used for higher traffic loads and deeper burial depths. 

The strength of a pipe depends on the thickness of the wall and the reinforcement provided. NP3 class Hume pipes have thicker walls and more reinforcement compared to NP2 class Hume pipes, which makes them more durable and can withstand higher loads and deeper burial depths.

Therefore, if you need a stronger and more durable pipe for your project, NP3 class Hume pipes would be a better choice than NP2 class Hume pipes.