A screw conveyor in a grain facility is a continuous rotating material path with several interfaces that require different inspection methods. The trough, cover, flight, shaft, intermediate hanger, end bearing, seal, drive, inlet, outlet, transition, gate, downstream route, and dust boundary can each affect conveying, product condition, leakage, and maintainability.

Grain silo screw conveyor hanger bearing and trough seal maintenance creates a traceable link between the conveyor identity, product route, flight and shaft condition, hanger bearing, trough clearance, end seal, drive, lubrication, dust path, isolation, corrective work, test result, and service record. This guide explains how to organize a project-specific review. It does not promise universal conveying capacity, bearing life, sealing efficiency, flight life, maintenance interval, cost reduction, safety, or regulatory compliance.

Define the screw-conveyor boundary

Start with a screw-conveyor register. Identify screw conveyor, auger, trough, cover, liner, flight, shaft, hanger bearing, hanger bracket, end bearing, tail bearing, head bearing, shaft seal, end seal, trough seal, flange, inlet, outlet, transition, chute, gate, valve, downstream conveyor, motor, gearbox, reducer, coupling, chain, sprocket, belt, pulley, guard, VFD, starter, sensors, overload, alarm, interlock, access route, and isolation point.

Record conveyor direction, product, batch, lot, moisture, fines, dust condition, temperature, expected flow, duty cycle, incline, fill condition, hanger arrangement, bearing type, seal type, drive type, downstream readiness, cleaning method, product-changeover requirement, maintenance history, spare parts, and acceptance criteria.

Keep screw-conveyor maintenance separate from general feeder maintenance, rotary-valve maintenance, blockage response, transfer-point wear, dust-collector maintenance, and product-changeover planning while documenting their interfaces.

Inspect flights, shafts, and trough clearance

Inspect screw flight, ribbon or paddle section, flight edge, center shaft, shaft pipe, coupling, end plate, welds, trough, trough liner, cover, inspection opening, hanger opening, inlet, outlet, transition, and discharge gate.

Look for worn flight edges, bent flights, cracked welds, shaft deformation, runout, misalignment, damaged couplings, trough wear, liner loss, contact marks, rubbing, buildup, caking, bridging, plugging, wet grain, fines, foreign material, corrosion, abrasion, and a clearance that changes along the conveyor.

Measure flight-to-trough, hanger-to-shaft, end, and cover clearances only with the approved equipment method, safe access, instruments, and project limits. Record measurement point, shaft position, instrument, value, condition, reference, deviation, repair decision, and retest. A screw that turns manually is not automatically fit for loaded operation.

Inspect intermediate hanger bearings

Inspect hanger bearing, bushing, bearing insert, hanger bracket, support rod, shaft collar, fasteners, lubrication point, bearing surface, dust shield, clearance, alignment, and nearby flight section.

Look for wear, loss of material, cracking, heat, discoloration, dry running, grease contamination, product ingress, shaft scoring, looseness, bracket deformation, bent support rods, loose fasteners, misalignment, vibration, abnormal noise, and a hanger that touches the shaft or restricts the flight.

Review whether the bearing material, lubrication method, temperature, product, moisture, fines, and operating condition match the approved equipment information. Record hanger location, bearing identity, measured condition, shaft condition, support condition, lubrication, temperature, vibration, noise, replacement reason, approved spare part, and retest.

Inspect end seals, trough seals, and dust paths

Inspect head and tail seals, shaft seals, packing, lip seals, labyrinth seals, mechanical seals, trough cover gaskets, flange gaskets, flexible seals, end plates, inspection covers, inlet transitions, outlet transitions, and nearby dust-collection connections.

Look for dust leakage, air leakage, product leakage, worn packing, damaged lips, hardening, displacement, gaps, uneven compression, oil contamination, moisture, corrosion, loose covers, failed gaskets, pressure imbalance, and dust trails at the head, tail, cover, hanger access, or transition.

Record seal type, contact surface, compression, joint, lubricant or packing condition, surface preparation, fasteners, pressure or suction condition, leakage observation, repair, replacement part, installation method, and post-maintenance check. More sealant does not automatically correct shaft runout, a worn surface, a distorted flange, or incorrect pressure conditions.

Check drive, bearings, and lubrication

Inspect motor, gearbox, reducer, coupling, chain, sprocket, belt, pulley, drive base, guard, head bearing, tail bearing, shaft, fasteners, grease points, oil, oil seals, temperature, vibration, noise, motor current, torque, overload, and VFD or starter.

Look for overheating, dry or contaminated lubricant, excessive grease, oil leakage, bearing looseness, gearbox noise, coupling misalignment, belt slip, chain slack, sprocket wear, loose base bolts, damaged guards, current increase, torque increase, overload trips, and rotation in the wrong direction.

Record drive condition, lubrication state, oil or grease condition, temperature, vibration, motor current, operating mode, rotation direction, overload state, repair, approved replacement part, and retest. Lubricant quantity and product must follow the actual equipment and approved procedure.

Review material flow, buildup, and product status

Trace material from inlet through the trough, over hangers, past the flights, through the outlet, gate, valve, chute, and downstream equipment. Identify low points, dead zones, underfilled sections, overfilled sections, areas of flight buildup, and locations where material can remain after the conveyor stops.

Look for bridging, caking, compacted grain, wet material, fines, foreign material, sudden release, carryback, spillage, dust, product retention around a hanger, seal contamination, cross-contact, and a discharge condition that does not match the approved route.

Define vacuuming, brushing, controlled disassembly, compressed-air restrictions, washdown restrictions, residue disposal, sanitation, pest prevention, product changeover, quality hold, quarantine, release, traceability, and cleaning verification.

Record previous product, current product, batch, lot, moisture, residue, foreign material, dust, cleaning method, quality status, and material requiring disposition.

Review controls, overloads, and interlocks

Review local control, remote control, manual mode, automatic mode, PLC, HMI, SCADA, motor starter, VFD, overload, current signal, torque signal, zero-speed switch, level switch, gate, valve, downstream conveyor, permissive, interlock, alarm, trip, emergency stop, reset, restart inhibit, and remote-start behavior.

Confirm that the screw conveyor cannot start against a blocked or unprepared downstream route, that the drive overload produces the intended response, that a zero-speed or current fault is visible, that an emergency stop prevents unintended restart, and that bypasses are controlled and recorded.

Look for a motor that runs while the screw is blocked, a zero-speed signal that remains healthy while the shaft is not moving, a high-current alarm that is ignored, a downstream conveyor that is stopped, a gate that is closed, or a reset that allows material movement before the trough and hanger are inspected.

Plan safe isolation before screw-conveyor work

Before opening a cover, removing a hanger, replacing a seal, adjusting a flight, or testing a conveyor, identify electrical energy, rotating equipment, stored grain, gravity, residual material, downstream movement, gates, valves, pneumatic or hydraulic devices, dust, fire, explosion, fall, pinch, entanglement, crush, and confined-space hazards.

Define lockout, tagout, upstream isolation, downstream isolation, drive isolation, electrical isolation, VFD discharge verification, pneumatic or hydraulic isolation, zero-energy verification, stored-material control, rotor or shaft restraint, guard control, access platform, fall protection, communication, standby, rescue, tool control, and release authority.

A stopped motor, open disconnect, closed gate, or empty-looking trough is not automatically proof that the shaft, flight, hanger bearing, stored grain, downstream route, or connected equipment is safe to work on.

Perform post-maintenance conveying tests

After corrective work, inspect trough, cover, flights, shaft, hangers, bearings, seals, end plates, drive, guards, inlet, outlet, chute, gates, valves, downstream route, sensors, controls, alarms, interlocks, access, tools, debris, and isolation restoration.

Where permitted, perform a controlled no-load rotation test followed by a controlled loaded conveying test. Observe rotation direction, noise, vibration, bearing temperature, motor current, torque, overload, flight movement, hanger behavior, seal leakage, dust, buildup, discharge, downstream readiness, alarm, emergency stop, and controlled restart.

Record product, batch, lot, fill condition, test boundary, method, instrument, baseline, clearance reference, bearing state, seal state, material movement, discharge condition, deviation, corrective action, retest, witness, and acceptance. A no-load rotation test alone does not represent every product, moisture condition, fill level, buildup state, or downstream operating condition.

Screw conveyor hanger and seal maintenance checklist

• The screw conveyor, route, trough, cover, flights, shaft, hangers, bearings, seals, drive, inlet, outlet, gates, valves, downstream equipment, controls, access, and isolation points are identified.
• Flights, edges, welds, shaft, couplings, trough, liners, cover, inspection openings, inlet, outlet, transitions, gates, and discharge are inspected for wear, damage, buildup, contact, misalignment, and obstruction.
• Hanger bearings, bushings, brackets, support rods, collars, fasteners, lubrication points, dust shields, clearances, alignment, temperature, vibration, noise, scoring, looseness, and deformation are checked.
• Head and tail seals, packing, lip seals, labyrinth seals, mechanical seals, trough-cover gaskets, flange gaskets, flexible seals, end plates, covers, pressure, suction, dust trails, and leakage are reviewed.
• Motor, gearbox, reducer, coupling, chain, sprocket, belt, pulley, drive base, guard, bearings, grease, oil, temperature, vibration, noise, current, torque, overload, and rotation direction are assessed.
• Product, batch, lot, moisture, fines, caking, bridging, plugging, residue, foreign material, dust, carryback, spillage, product retention, quality hold, release, cleaning, and traceability are controlled.
• Electrical, rotating, stored-grain, gravity, downstream-motion, gate, valve, pneumatic, hydraulic, dust, fire, explosion, fall, pinch, entanglement, crush, and confined-space controls are documented.
• No-load rotation and loaded conveying tests record product, fill, method, instrument, baseline, flight, hanger, seal, drive, discharge, downstream route, current, torque, alarms, deviation, retest, and acceptance.
• Bearing replacement, bushing replacement, seal replacement, flight repair, shaft repair, trough repair, hanger adjustment, lubrication service, sensor repair, spare parts, work orders, cleaning, training, and handover are recorded.
• No universal conveying capacity, bearing life, sealing efficiency, flight life, maintenance interval, cost, safety, or compliance claim is made without project evidence.