Which schedule pipe is acceptable for boiler blowdown lines?

Boiler blowdown lines are critical components in maintaining the efficiency and safety of a boiler system. The correct selection of pipe schedule for these lines is essential due to the high pressures and temperatures involved in boiler applications.

Schedule 80 pipes are designed to withstand higher pressure than Schedule 40 pipes because they have thicker walls. This increased wall thickness provides greater strength and durability, making Schedule 80 a suitable choice for boiler blowdown lines, where there can be sudden pressure changes and elevated temperatures. The robust nature of Schedule 80 helps to prevent failures or leaks, which could lead to significant safety hazards or operational interruptions.

In contrast, the other options, such as Schedule 40, Schedule 10, and Schedule 20, have thinner walls and may not possess the required strength to safely handle the high pressures and temperatures experienced in boiler blowdown applications. Therefore, while they may be appropriate for other plumbing applications, they are not recommended for blowdown lines where maintaining the integrity of the system is paramount.