Which component is not considered one of the four major components of a gate valve?

• A. Gland
• B. Body
• C. Bonnet
• D. Gate

Answer: (A)

The main idea here is identifying what parts truly define the valve’s functioning. A gate valve’s four major components are the body, which contains the flow path; the bonnet, which houses the stem and packing and bolts to the body; the gate, the movable barrier that blocks or allows flow; and the stem, which transmits the motion from the handwheel or actuator to raise or lower the gate. The gland, on the other hand, is part of the packing arrangement around the stem that helps seal against leakage. It isn’t one of the primary structural components that control isolation, so it’s not counted among the four major parts.