Question 611Steam Plants - Assistant Engineer

The correct answer is B) Shell-and-tube. The shell-and-tube type lube oil cooler is commonly used in marine applications, including those found on U.S. Coast Guard vessels. This design features a shell that encloses a bundle of tubes, with the lube oil flowing through the tubes and the cooling medium (typically seawater or freshwater) flowing over the outside of the tubes within the shell. This configuration allows for efficient heat transfer between the lube oil and the cooling medium, making it a suitable choice for marine engine applications. The other options are not correct because a plate-type cooler (A) has a different construction, a bundle-and-stack cooler (C) is a less common design, and a self-venting cooler (D) is a specialized type not typically found in the illustration provided.