What inspection and maintenance items are performed on a double block bleed (DBB) plug valve during a routine scheduled interval?

The identified correct response encompasses a comprehensive range of essential tasks that contribute to the effective maintenance of a double block bleed (DBB) plug valve. Routine inspections and maintenance play a crucial role in ensuring that the valve operates correctly and safely under pressurized conditions.

The aspect of assessing proper operation is critical; this involves ensuring that the valve opens and closes smoothly and that it is functioning according to specifications. This is necessary to prevent any operational failures that could compromise system integrity.

Checking for leaks is another vital task. A DBB valve's design incorporates two seal points to provide a double barrier against the flow of fluids; therefore, ensuring that there are no leaks is essential to maintaining safety and performance. Any leaks could indicate failure in one of the sealing surfaces, which could lead to hazardous situations.

Additionally, operator lubrication contributes to the smooth functioning of the device. Proper lubrication minimizes wear and tear on the mechanical components, thereby extending the life of the valve. Moreover, corrosion control is critical because environmental factors can lead to deterioration over time, which can compromise the valves' effectiveness.

None of the other options provide a complete picture of what is needed for a thorough inspection and maintenance routine. While they may include some relevant items, they lack the comprehensive approach that prioritizes