How to Handle Centrifugal Pump Seal Leakage

Centrifugal pump seal leakage is a common issue during pump operation. Proper handling depends on the type of seal and the cause of the leakage. This guide explains how to identify, troubleshoot, and prevent seal leakage effectively.

1. Identify the Type of Leakage

Pump seal leakage is generally classified into two types:

• Mechanical Seal Leakage: Occurs between the pump shaft and the pump casing, where fluid leaks from the seal end.

• Packing Seal Leakage: Occurs at the pump shaft packing, where fluid seeps through the gland area.

2. Handling Mechanical Seal Leakage

1. Check for Wear or Damage

   • Inspect the seal faces for wear, cracks, or chipping. Replace the mechanical seal if it is damaged.

2. Verify Proper Installation

   • Ensure the seal is installed in the correct orientation and the faces are aligned without tilt.

3. Inspect Shaft and Sleeve

   • Check the pump shaft for scratches or corrosion. Repair or replace the shaft sleeve if necessary.

4. Check Operating Conditions

   • Make sure the pump is running within the seal’s pressure and temperature limits. Adjust operating conditions if needed.

5. Adjust Seal Flush or Cooling System

   • For mechanical seals requiring a flush or cooling liquid, ensure proper flow and temperature.

3. Handling Packing Seal Leakage

1. Adjust Gland Packing Pressure

   • Avoid over-tightening, which can cause overheating and damage, or under-tightening, which can lead to severe leakage.

2. Check Packing Condition

   • Replace packing if it is worn, hardened, or damaged.

3. Use Proper Lubrication

   • Some media require lubrication or cooling water to reduce friction and prolong packing life.

4. Regular Maintenance

   • Periodically adjust packing tightness to maintain a proper seal.

4. Preventive Measures

• Regularly inspect shaft alignment and pump vibration to avoid uneven wear.

• Use seals compatible with the pumped fluid and operating conditions.

• Conduct routine maintenance and replace old or worn seals in time.

• Operate the pump within design parameters to avoid overpressure or dry running.