Mechanical seals are precision engineered components. In order to get better seal performance and expected seal life, it must be installed properly and fitted in good conditions.
Proper Seal Installation Procedures for most Centrifugal Pumps
-Handle the seal with extreme care at all times. Hands should be clean and soft paper towel or cloth should be used if the seal faces are to be pushed or touched.
-Seal faces are very brittle and will crack or chip if mistreated. If you drop a seal, do not install it before checking to make sure that the seal is free of chips, cracks, or other damage that would cause the seal to leak during operation
-Ensure there is free of sharp corners or burrs on shafts or housings.
- Ensure the squareness of stuffing box face to shaft centerline to within 0.05mm(0.002”)
-Ensure the shaft radial movement to within 0.05mm(0.002”), and axial movement to within 0.10mm(0.004”)
- Ensure the shaft is concentric with the bore of the adaptor(seal chamber) to within 0.5mm (0.020”).
- Lubricate shaft/sleeve and O-rings with a suitable lubricant and lightly slide the seal onto the shaft
- Do not use excessive force to install a mechanical seal. If it is difficult to install, something is wrong.
- Do not hammer on the seal or shaft/sleeve
- Ensure the seal is fitted to its correct working length.
- Evenly tighten gland bolts
-Be sure all set screws are tightened to the shaft.
-If it’s a cartridge seal, ensure loosen the setting clip locking screws and remove the setting clips or move the setting clips to the correct position and then tighten the locking screws to set the clips in this position.
-Before start up equipment, turn shaft by hand to check for free rotation.
- The pump must be fully filled with liquid before start up the equipment.
-Cooling system should be considered if the process temperature over 80¡æ(176¨H).
-Ensure keep cooling piping valve opened before start up the equipment.
-Prevent cavitations as this will shorten the seal’s life.
-Never allow pumps to run dry - this will result in premature seal failure