| Mechanical Seal |
Confirm shaft diameter, stationary-seat dimensions, rotating-face arrangement, seal chamber depth, and spring direction. Check the pump model and original seal drawing. |
Material compatibility, pressure rating, temperature range, shaft speed, face combination, and elastomer type. |
Clean the shaft and seal chamber; inspect for burrs; lubricate only as permitted by the seal instructions; avoid touching polished seal faces. |
Inspect for leakage, heat discoloration, vibration, and abnormal noise. Check alignment and dry-running events that can damage the faces. |
Visible leakage, face damage, hardened elastomers, excessive wear, or repeated leakage after correct installation. |
High |
| Gasket or O-Ring |
Match groove dimensions, cross-section, inside diameter, flange profile, and compression requirements. Never select by outside diameter alone. |
Fluid compatibility, temperature rating, pressure rating, hardness, and resistance to swelling or chemical attack. |
Use the correct groove and seating surface; remove old material; avoid twisting O-rings; apply compatible lubricant where specified. |
Check for flattening, cuts, extrusion, cracking, swelling, and compression-set during scheduled inspections. |
Leakage, permanent deformation, cracking, chemical swelling, or removal of the connected joint. |
High |
| Impeller |
Verify pump series, impeller diameter, vane count, bore, keyway, balance grade, rotation direction, and required clearance. |
Flow rate, total head, rotational speed, fluid solids content, material, and closed-, open-, or semi-open design. |
Check shaft and key condition; set wear clearance according to the pump service manual; confirm correct rotation before full operation. |
Inspect for erosion, corrosion, clogging, cracks, imbalance, and vane wear. Clean passages without damaging the surfaces. |
Reduced flow or head, excessive vibration, damaged vanes, severe wear, or performance outside the duty point. |
High |
| Wear Ring |
Measure both the impeller and casing wear surfaces. Match inside diameter, outside diameter, axial width, and specified running clearance. |
Material, clearance limits, interference fit, operating temperature, and fluid abrasiveness. |
Remove the old ring without damaging the casing; verify fit and concentricity; restore the specified clearance after assembly. |
Measure clearance at planned intervals and inspect for scoring, ovality, and abrasive wear. |
Clearance exceeds the service limit, efficiency drops, internal recirculation increases, or surfaces become scored. |
High |
| Shaft or Shaft Sleeve |
Confirm overall length, diameter, keyway, threads, seal location, bearing seats, runout limit, and coupling dimensions. |
Material strength, corrosion resistance, hardness at seal contact areas, maximum speed, and allowable runout. |
Protect machined surfaces; check straightness and runout with suitable measuring equipment; verify key fit and coupling alignment. |
Inspect for grooving, corrosion, fretting, bending, and wear beneath seals or bearings. |
Excessive runout, deep seal grooves, damaged threads or keyways, corrosion loss, or inability to maintain alignment. |
High |
| Bearings |
Match bearing designation, bore, outside diameter, width, internal clearance, load rating, and mounting arrangement. |
Radial and axial loads, speed, operating temperature, lubrication method, and environmental contamination. |
Use clean tools and correct mounting force; apply force only to the ring being fitted; do not strike the bearing directly. |
Monitor temperature, vibration, noise, lubrication condition, and shaft movement. Prevent water and dirt ingress. |
Rising temperature, abnormal noise, vibration, rough rotation, discoloration, or excessive radial or axial play. |
High |
| Coupling Element |
Verify coupling size, bore, keyway, spacer length, torque capacity, speed rating, and compatibility with the coupling hubs. |
Transmitted torque, misalignment limits, service factor, temperature, electrical isolation needs, and guard clearance. |
Align shafts before installation; set the correct gap; install the guard; tighten fasteners to the specified torque. |
Inspect for cracks, hardening, tooth wear, loose fasteners, and signs of angular or parallel misalignment. |
Cracking, deformation, excessive backlash, repeated element failure, or misalignment that cannot be corrected. |
Medium |
| Bearing Housing |
Match mounting pattern, bearing seats, shaft centerline height, oil or grease arrangement, and seal locations. |
Material, bearing fit tolerances, lubrication capacity, drain and vent provisions, and operating temperature. |
Clean all mating surfaces; inspect bearing bores for fretting; verify centerline and fastener condition before final tightening. |
Check oil level or grease condition, housing temperature, contamination, cracks, and mounting-bolt tightness. |
Damaged bearing seats, cracks, persistent lubricant leakage, distortion, or inability to maintain bearing alignment. |
Medium |
| Suction or Discharge Flange Gasket |
Match flange nominal size, pressure class, bolt-hole pattern, gasket type, thickness, and facing arrangement. |
Fluid compatibility, pressure and temperature rating, flange material, bolt load, and surface finish. |
Clean flange faces; center the gasket; avoid using a gasket that blocks the flow path; tighten bolts in a cross pattern. |
Inspect for external leakage, bolt relaxation, flange distortion, and gasket extrusion during system checks. |
Leakage, damaged flange faces, disassembly of the joint, or evidence of chemical or thermal degradation. |
High |
| Check Valve |
Confirm line size, connection type, flow direction, pressure class, cracking pressure, and installation orientation. |
Flow rate, fluid viscosity, solids content, pressure, temperature, and allowable pressure loss. |
Install the arrow in the flow direction; provide adequate pipe support; keep the valve accessible for inspection and cleaning. |
Check for reverse flow, water hammer, sticking, noise, seat wear, and debris accumulation. |
Reverse flow, failure to close, excessive pressure loss, repeated water hammer, or damaged seat and disc. |
Medium |
| Pressure Gauge or Sensor |
Match connection size, thread standard, pressure range, accuracy, wetted materials, electrical output, and environmental rating. |
Normal and maximum pressure, pulsation, temperature, fluid compatibility, calibration range, and signal type. |
Install with an isolation valve or suitable snubber where needed; protect from vibration and excessive temperature; verify sealing method. |
Compare readings with a reference instrument, inspect for leakage, and check calibration at the interval required by the control system. |
Inconsistent readings, zero drift, damaged display, blocked impulse path, leakage, or failed calibration. |
Medium |
| Motor or Drive-End Fan |
Verify motor frame, power, voltage, frequency, speed, mounting arrangement, shaft dimensions, and overload protection. |
Required pump speed, torque, duty cycle, enclosure, efficiency class, ambient temperature, and hazardous-area requirements where applicable. |
Confirm electrical isolation, grounding, rotation direction, coupling alignment, ventilation, and correct overload settings. |
Keep ventilation passages clean; inspect terminals, bearings, vibration, temperature, and fan condition. |
Overheating, insulation failure, abnormal current, excessive vibration, damaged fan, or inability to reach operating speed. |
High |
| Baseplate and Mounting Fasteners |
Match bolt pattern, pump and motor footprint, shaft centerline height, anchor locations, and allowable structural load. |
Material, stiffness, anchor size, grout or isolation arrangement, vibration level, and corrosion environment. |
Level and secure the base; correct soft foot; align the pump and driver after final piping connection; tighten anchors correctly. |
Inspect anchor torque, corrosion, grout condition, cracks, vibration, and changes in alignment. |
Persistent misalignment, cracked grout, loose anchors, deformation, corrosion loss, or abnormal vibration. |
Medium |
