Question 49 UFIV01 - Chief Engineer - UFIV

The Correct Answer is C ### Why Option C ("Wire-mesh filter element.") is correct: Wire-mesh filter elements (often oiled or dry) are designed to be durable and are typically used in heavy-duty or industrial applications, including large marine diesel engines, as a primary or pre-filter stage. Their construction allows them to be easily cleaned—usually by washing them in a solvent or detergent solution, blowing them dry with compressed air, and sometimes re-oiling them—rather than being discarded. This periodic cleaning and reuse is a defining characteristic of heavy-duty wire-mesh or screen-type elements, making them cost-effective for large vessel operations. ### Why the other options are incorrect: * **A) Spiral-rotor filter element:** This option typically refers to a type of pre-cleaner (often inertial or centrifugal) that separates heavier contaminants before the main filter element. While the collection bowl or mechanism might be cleaned, the primary filtration element is not typically a "spiral-rotor" in the context of the final stage filter element being cleaned and reused in the same manner as a wire mesh. These devices are more about continuous contaminant rejection than filtration via a reusable fibrous or screen medium. * **B) Multi-tube filter element:** This term generally refers to a design incorporating multiple small, disposable paper or synthetic tubes/cartridges to achieve a large surface area. These tubes rely on depth or surface filtration from the media itself (like pleated paper) and are designed to be replaced entirely when clogged, not cleaned and reused. * **D) Panel-type filter element:** While some specialty panel filters (e.g., HVAC) can be cleaned, in the context of high-efficiency diesel engine intake filters, "panel-type" usually denotes a pleated paper, synthetic, or glass fiber media enclosed in a frame. These highly efficient media capture very fine dust particles and cannot be effectively cleaned without damaging the fine fiber structure, thus they must be periodically replaced.