
Appendix A 233
Q4.
Pump draws higher amps than specified
A4.
• Speed too high
• Process liquid of higher viscosity / specific gravity than originally quoted
being pumped
• Oversized impeller installed
• Total head of system either higher or lower than anticipated
• Misalignment between pump and driver
• Rotating parts in contact with stationary parts
• Worn or damaged bearings
• Packing improperly installed
• Incorrect type of packing
• Mechanical seal exerts excessive pressure on seat
• Gland too tight
• Improper lubrication of bearings
• Too much lubricant in bearings
• Bent shaft
• Uneven thermal expansion