Which statement about pump lubrication is false?

Which statement about pump lubrication is false?

• A. Bearings can be over lubricated
• B. Most pumps are self-priming
• C. Fire point is defined as the point at which a lubricant will burn
• D. Oil is used in high rpm conditions, grease is used in low speeds and heavy loads

Answer: (B)

The statement that most pumps are self-priming is not correct. Priming fills the suction line with liquid and removes air so the pump can develop suction; while some pumps are designed to be self-priming, the majority used in typical water treatment systems are not. They require manual priming or a priming device. That’s why this choice is false. For context, bearing lubrication isn’t a simple “more is better” situation—over-lubricating can cause excessive heat, churning, and potential seal or bearing problems. The fire point described in basic terms is the temperature at which a lubricant will continue to burn after ignition, which is the standard classroom distinction you’d rely on. And choosing oil for high-speed, high-RPM operation while reserving grease for low-speed, heavy-load conditions reflects common practice: oil handles rapid motion well, while grease stays in place longer under heavy loads and slower movement.

The statement that most pumps are self-priming is not correct. Priming fills the suction line with liquid and removes air so the pump can develop suction; while some pumps are designed to be self-priming, the majority used in typical water treatment systems are not. They require manual priming or a priming device. That’s why this choice is false.

For context, bearing lubrication isn’t a simple “more is better” situation—over-lubricating can cause excessive heat, churning, and potential seal or bearing problems. The fire point described in basic terms is the temperature at which a lubricant will continue to burn after ignition, which is the standard classroom distinction you’d rely on. And choosing oil for high-speed, high-RPM operation while reserving grease for low-speed, heavy-load conditions reflects common practice: oil handles rapid motion well, while grease stays in place longer under heavy loads and slower movement.