The document describes different types of valves used in the oil and gas industry. It lists general valves such as gate valves, ball valves, plug valves, globe valves, and butterfly valves. It also discusses pressure safety valves like relief valves and surface safety valves. For each valve type, it provides a list of the main components. Gate valves, plug valves, globe valves, and relief valves each have their components described in more detail. The document also includes brief sections on common gasket materials and lapping paste grit sizes used for valve maintenance.
