🔍 Key Concepts

• Flash type distilling plant operation and vacuum conditions • Typical paths for air leaks into closed low-pressure systems • Locations and functions of gaskets, valve stems, and gage glass packings on piping and vessels

💭 Think About

• In a flash distilling plant, think about where metal parts are joined and where moving parts penetrate the pressure boundary. Which of these spots can realistically let air in if sealing is not perfect? • For each listed item (gasketed joint, valve stem, gage glass packing), ask yourself: is this a sealing surface that separates the inside of the system from the outside atmosphere? • Consider how maintenance issues (worn packing, loose bolts, hardened gaskets) affect tightness. Would those issues be limited to just one of the options, or could they apply to more than one?

✅ Before You Answer

• Verify which components actually pierce the pressure boundary of the distilling plant shell or connected piping • Check which listed items rely on packing or gaskets to prevent leakage between the inside and the atmosphere • Confirm whether air leaks can occur through any single one of these points, and then decide what that implies about the group of answer choices