Final answer:
Packing in a stuffing box is designed to minimize, not completely stop, leakage while lubricating the packing material to prevent friction and wear on the moving shaft. Complete prevention of leakage is not the goal, as a controlled amount is necessary for lubrication. Regular adjustment and maintenance are essential for effectiveness.
Step-by-step explanation:
The statement "Packing in the stuffing box is designed to stop leaking entirely" is false. The primary function of a stuffing box in many engineering applications, such as pumps and valves, is to contain the fluids or gases within the machinery and prevent leakage. However, the packing within a stuffing box is not designed to completely stop all leaks; rather, it is designed to minimize leakage to a manageable rate while still allowing for the proper functioning of the moving parts it surrounds. It is important for a controlled amount of fluid to lubricate the packing material, which in turn reduces friction and wear on the moving shaft.
Stuffing boxes, therefore, strike a balance between sealing and lubrication. Adjustment and maintenance of the packing are often necessary to ensure the stuffing box performs effectively over time, as packing materials can degrade or require re-tightening to maintain the ideal balance between sealing and minimal leakage.