Page 252 - Intro Predictive Maintenance

Process Parameters 243

Table 10–12 Common Failure Modes of Baghouses

THE PROBLEM
Continuous Release of Dust-Laden Air Intermittent Release of Dust-Laden Air Loss of Plant Air Pressure Blow-Down Ineffective Excessive Differential Pressure Fan/Blower Motor Trips Fan Has High Vibration Premature Bag Failures Differential Pressure Too Low Chronic Plugging of Bags

THE CAUSES Insufficient Capacity
Bag Material Incompatible for Application
Bag Plugged
Bag Torn or Improperly Installed
Baghouse Undersized
Blow-Down Cycle Interval Too Long
Blow-Down Cycle Time Failed or Damaged
Blow-Down Nozzles Plugged
Blow-Down Pilot Valve Failed to Open (Solenoid Failure)
Dust Load Exceeds Capacity
Excessive Demand
Fan/Blower Not Operating Properly
Improper or Inadequate Lubrication
Leaks in Ductwork or Baghouse
Misalignment of Fan and Motor
Moisture Content Too High
Not Enough Blow-Down Air (Pressure and Volume)
Not Enough Dust Layer on Filter Bags
Piping/Valve Leaks
Plate-Out (Dust Build-up on Fan’s Rotor)
Plenum Cracked or Seal Defective
Rotor Imbalanced
Ruptured Blow-Down Diaphrams
Suction Ductwork Blocked or Plugged
Source: Integrated Systems, Inc.

ation in one direction only. Failure is often caused by inappropriate bidirectional
operation of the gearbox or backward installation of the gear set. Unless specifically
manufactured for bidirectional operation, the “nonpower” side of the gear’s teeth is
not finished. Therefore, this side is rougher and does not provide the same tolerance
as the finished “power” side.