Here are some common signs to look for that could indicate an offset butterfly valve is sticking, wearing out, or damaged:
Difficulty operating/high torque requirements
The valve shouldn’t require excessive force to open/close.
Leakage when closed
Look for fluid seeping past the disc edge or shaft seal, indicating worn seals or damage.
Noise/vibration
Grinding, clacking sounds could mean worn bearings or internal parts are loose.
Fluid residue/buildup
Excess debris inside could cause corrosion or jamming over time.
Visual wear/corrosion
Pitting, scratches or material loss on disc, seat or shaft surfaces decrease lifespan.
Cracks in body/disc material
Especially in older cast valves, cracks allow leakage.
Bent or damaged shaft
May occur from over-torqueing or shock during service.
Scored or rough disc/seat surfaces
Interference prevents tight shutoff.
Periodic routine exercising, inspection and lubrication/maintenance helps ensure offset butterfly valves continue functioning properly.