A filter

摘要

A filter includes a filter element having an interior surface defining an inner chamber and a standpipe extending through the inner chamber and terminating at a point that allows air that flows from outside the filter element through the filter element and into the inner chamber to flow into the standpipe and out of the filter, while preventing fluid flowing from the opposite direction through the standpipe from entering the filter element. The filter can be used to filter air flowing from the filter to a downstream component, while preventing fluid from flowing from the filter to the downstream component and preventing a substance, such as urea or fuel, entering the filter from the downstream component from degrading the filter element in the filter.