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CHDF Horizontal Multistage Stainless Steel Pump

Preventive Maintenance Schedule & Best Practices

1. Daily Inspection Checklist

Item	Check Method	Normal Condition	Action if Abnormal
Noise Level	Listen	Smooth, quiet operation	Investigate source
Vibration	Touch/Measure	Minimal vibration	Check alignment
Bearing Temp	Infrared thermometer	<70°C	Check lubrication
Seal Leakage	Visual	<3 drops/min	Tighten or replace
Motor Current	Ammeter	≤ Rated current	Check load
Pressure	Gauge reading	Within design range	Check system

2. Weekly Maintenance Tasks

2.1 Visual Inspection

• ✓ Check for external leaks at seals and gaskets
• ✓ Inspect foundation bolts for tightness
• ✓ Verify pipe supports are secure
• ✓ Check coupling guard is in place
• ✓ Clean motor cooling fins of dust/debris

2.2 Operational Checks

• Record suction and discharge pressure
• Record motor amperage on all three phases
• Check for unusual noises during start/stop
• Verify control panel indicators are normal

3. Monthly Maintenance

3.1 Bearing Lubrication

3.2 Mechanical Seal Inspection

• Check for visible leakage
• Inspect seal flush line (if equipped)
• Verify seal chamber temperature
• Check for shaft scoring

4. Quarterly Maintenance (Every 3 Months)

4.1 Performance Testing

Test	Procedure	Acceptable Range
Flow Rate	Measure with flow meter	±5% of design
Total Head	Discharge – Suction pressure	±5% of curve
Power Consumption	Power analyzer	≤ Nameplate kW
Efficiency	Calculate from above	≥ 70% of BEP

4.2 Vibration Analysis

Measure vibration at bearing housings in three directions:

• Horizontal (radial)
• Vertical (radial)
• Axial (thrust)

4.3 Electrical Testing

• Insulation resistance test (megger) – Min 1 MΩ
• Phase balance check – Max 5% imbalance
• Ground continuity test – Max 0.1 Ω

5. Semi-Annual Maintenance (Every 6 Months)

5.1 Alignment Check

5.2 Seal Replacement Planning

Plan mechanical seal replacement if:

• Operating hours > 8,000
• Leakage exceeds 10 drops/min
• Visible scoring on seal faces

6. Annual Maintenance (Major Overhaul)

6.1 Complete Disassembly Inspection

1. Impeller Inspection:
   • Check for erosion/corrosion
   • Measure wear ring clearance
   • Replace if clearance > 2x original
2. Shaft Inspection:
   • Check for straightness (max 0.05mm TIR)
   • Inspect seal sleeve for scoring
   • Check keyway for wear
3. Bearing Replacement:
   • Replace all bearings annually
   • Use proper puller tools
   • Heat new bearings to 110°C for installation
4. Casing Inspection:
   • Check for erosion or corrosion
   • Inspect gasket surfaces
   • Pressure test if cracks suspected

6.2 Reassembly Specifications

Component	Torque (Nm)	Notes
Base bolts	Per bolt size chart	Use thread locker
Casing bolts	Even torque sequence	Cross pattern
Coupling bolts	Per coupling manual	Check shear pins

7. Long-Term Storage

7.1 Storage Preparation

1. Drain all liquid from pump
2. Clean internal components
3. Apply rust preventive coating
4. Fill bearings with fresh grease
5. Seal all openings with tape/caps
6. Store in dry location (humidity <60%)

7.2 Storage Maintenance

• Rotate shaft monthly (10 revolutions)
• Inspect quarterly for corrosion
• Reapply rust preventive annually

8. Maintenance Record Template

Date	Hours	Task	Parts Used	Technician	Next Due
____	____	____	____	____	____

9. Spare Parts Recommendation

Critical Spares to Keep On-Hand:

• ✓ Mechanical seal kit (1 set)
• ✓ Bearings (1 set)
• ✓ Gasket kit (1 set)
• ✓ O-rings (assorted)
• ✓ Grease (1 cartridge)

10. Safety During Maintenance

11. Contact Support

Shanghai Chaodun Machinery Manufacturing Group Co., Ltd.

Website: https://cd-pump.com