🔍 Key Concepts

• How a scored (damaged) valve stem moves through packing material • The purpose of valve stem packing and what causes it to fail • Which parts of a valve are actually in contact with the packing (stem vs. disk vs. seat)

💭 Think About

• When you repack a valve, which component is directly affected by the new packing: the stem, the disk, or the seat? • How would a rough, scored surface moving through soft packing material affect that packing over time? • Which options describe damage that would more likely come from poor seating or fluid flow, rather than from stem/packing issues?

✅ Before You Answer

• Identify which answer choices involve packing problems versus disk or seat damage. • Focus on the effect of a rough, scored stem sliding through packing when the valve is opened and closed repeatedly. • Eliminate any options that mainly involve parts of the valve that do not contact the packing directly (like the disk face or seat).