Which valve requires specific and routine lubrication?

The tapered plug valve is designed with a plug that has a tapered shape, allowing it to fit snugly against the valve seat to control flow. Due to its specific design characteristics, this type of valve requires regular lubrication to maintain proper operation. The lubrication helps reduce friction between the plug and the valve body, ensuring smooth movement and preventing wear over time. This routine maintenance is vital for preventing seizing or binding of the tapered plug, which could lead to operational difficulties or even valve failure.

In contrast, ball valves and check valves typically use a different design that does not necessitate the same level of routine lubrication. Ball valves have a smooth, rotating sphere and are generally self-lubricating due to their materials and design, while check valves are designed to allow flow in one direction and rely on hydraulic forces to operate, thus they do not need regular lubrication either. The lift check valve operates through a disc or ball mechanism, which also functions efficiently without the need for routine lubrication.

Overall, the need for specific and routine lubrication sets tapered plug valves apart, making them distinct in terms of maintenance requirements compared to the other types of valves listed.