These steps outline the necessary procedures to ensure the safety and proper handling of the pump during maintenance work. Here is a summary of the steps:
Start by isolating the pump:
- Close the suction, discharge, recycle, casing drain, and vent line isolation valves.
- Attach "DO NOT OPERATE" isolation tags to all isolation valves.
- Disconnect the pump from local push buttons and breakers in the substation.
- Lock the motor breaker with the help of an electrician.
- Attach "DO NOT OPERATE" tags to the local push button and breaker lock.
- Completely drain the pump.
- If it's a chemical pump, flush it with water until the water runs clear.
- If it's a hydrocarbon pump, purge it with N2 to bring the Lower Explosive Limit (LEL) down to 0%.
- Blind the suction, discharge, and recycle lines.
- If the pump casing drain is connected to a closed drain system, blind the drain line.
- If the pump casing vent line is connected to the flare system, blind the vent line.
- Attach "DO NOT OPERATE" isolation tags to all blinds.
Hand over to maintenance:
- Once blinding is complete, the pump is ready to be handed over to maintenance.
- Maintenance can perform repair work such as mechanical seal replacement, impeller repair, bearing replacement, or removal of the pump to the workshop.
Optional: Cleaning the pump suction strainer:
- If cleaning the pump suction strainer is necessary, isolation, draining, and purging are sufficient.
- Blinds are not required for this task.
Please note that these steps serve as a general guideline, and it's important to consult the specific procedures and safety guidelines provided by your organization or follow any applicable industry standards.
