Visual Testing (VT) Practice Exam 2025 - Free VT Exam Practice Questions and Study Guide

A mechanical device that controls flow is termed a valve. Valves are designed specifically to regulate, direct, or control the flow of fluids (liquids, gases, or slurries), as well as to manage pressure within a system. They can be manipulated to open, close, or partially obstruct the flow, making them crucial in various applications, from plumbing to industrial processes.

Though pumps and snubbers might be involved in flow systems, their functions differ. Pumps are active devices that move fluids by converting mechanical energy into hydraulic energy, which is essential for transportation of liquids from one place to another. Snubbers, on the other hand, are used primarily to absorb shock or vibration in a system, and they do not directly control flow in the sense that valves do.

Given that valves are fundamentally meant for the control of flow, they are the most precise answer to the question regarding a mechanical device designated for that purpose.