ASME Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The upper limit for the viscosity of #6 oil when using steam atomization is indeed around 300 SSU (Saybolt Seconds Universal). This viscosity is critical in ensuring that the atomization process is effective. Steam atomization relies on the ability of the steam to break up the oil into fine droplets; if the viscosity is too high, the oil will not atomize effectively, leading to larger droplets that can negatively affect combustion efficiency and increase emissions.

Viscosity measurements dictate how easily a fluid can flow; #6 oil, which is a heavy fuel oil, typically falls around this range, where optimal atomization is achieved. At viscosities higher than 300 SSU, the chances of inadequate atomization increase, reducing the effectiveness of the steam in generating a fine mist.

The values of 200 SSU, 250 SSU, and 350 SSU represent limits that are either too low or considerably higher than the optimal working range. Therefore, while 200 SSU is quite low for effective steam atomization of #6 oil, and 250 SSU approaches the threshold for good atomization, 350 SSU exceeds the recommended limit, leading to poor performance and potential operational issues.

Focusing on the practical application,