Power Plant Boiler feed pump

BEST PRACTICES FOR CONDITION MONITORING AND MAINTENANCE OF

BOILER FEED PUMP

V.GauthamBE Power NPTI

MBA SIMSREE(2014-16)

INTRODUCTION

Function of BFP – transport water from feed storage tank to boiler drum through H.P heater, F.R.S and economizer

Types of BFP – KHI and FK series

Need for maintenance

AIMS AND OBJECTIVES OF MAINTENANCE OF BFP

To maintain BFP at its maximum operating efficiency

To safeguard investment To help management in taking

decisions Make best use of resources. Maintain plant parameters

TECHNICAL DETAILS OF BFP

Pump type: FK 6D30 Flow rate: 398 cum/hr Speed: 5075 rpm Input Power: 2558 kw Efficiency: 81 % Min. RC flow: 100 tonnes/hr No. of stages: 6

BFP EXTERNALS

BFP INTERNALS

Maintenance

The BFP is a critical auxiliary which has to work continuously.

Maintenance types : Breakdown maintenance Preventive Reliability centered maintenance Condition monitoring Computer management maintenance

system(CMMS)

BREAKDOWN MAINTENANCE

Breakdown maintenance involves the repair or replacement of equipment and components after they have failed.

Activities which are undertaken when the BFP stops working come under breakdown maintenance

s.n Clearance between Clearance(in mm)

01.

0203.04.05.

06.

Impeller wearing-Casing wear ring/Diffuser wear ring.Balance drum-Restriction bush.Total axial float.Thrust/Axial bearing clearanceJournal bearing clearance (Top clearance)Interference of thrust collar & shaft

0.4

0.248.00.25 to 0.400.15 to 0.18

0.09

Preventive maintenance

It includes cleaning, inspection, oiling and retightening

It is the work done primarily to rectify the effects of normal wear in pump.

The usual intervals of preventive maintenance are:

Daily Monthly Quarterly Half yearly Annually

Predictive maintenance

It includes the following - Visual and sound monitoring Contaminant or debris monitoring Performance and behaviour monitoring thermograph monitoring Shock pulse monitoring. Vibration monitoring.

 Vibration monitoring

COMPUTERIZED MAINTAINANCE MANAGEMENT SYSTEM

It is a type of management software that performs functions in support of management and tracking of operation and maintenance activities.

Historical tracking of all work orders generated which become sortable by equipment, date ,person responding etc.

Tracking of scheduled and unscheduled maintenance activities.

Storing of maintenance procedures as well as all warranty information by component.

Storing of all technical documentation or procedures by component.

CMMS BENEFITS

Detection of impending problems before a failure occurs resulting in fewer failures.

Achieving a higher level of plant maintenance activities that enables a more efficient use of staff resources.

Maintaining optimal equipment performance that reduces downtime and results in longer equipment life.

Shaft alignment

Shaft Alignment – Shaft alignment is the process of matching the centerline of two shafts. There is a one driving and another one is driven shaft.

Misalignment -It is the deviation in the centerline and plane of two shafts.

Radial misalignment Axial misalignment Combined misalignment

MotorPump

MotorPump

Axial or angular misalignment

Radial misalignment

Motor

Pump

Combined misalignment

Procedure for cartridge replacement

BFP PERMISSIVES

1. Deaerator level normal(2375mm).

2. BFP suction valve open.

3. Auxiliary oil pump on lube oil pressure more than 2.5 kg/cm2.

4. Discharge valve closed, recirculation valve open.

5. Working oil temperature less than 130˚C.

6. Differential temperature across feed pump suction and discharge less than 12˚C.

Boiler feed pump Log Book

TroubleshootingSr. no

Symptom Possible cause Action

1. Pump does not deliver rated quantity

•Pump not upto rated speed

•Restriction in delivery pipe work or incorrect

•Blockage in impeller or casing

•High fluid viscosity

• Increase speed

• Clear obstruction or rectify error in pipe work

• Remove half casing and clear obstruction

• Check the recommended viscosity

2. Bearing overheating

•Defect in lubricating oil system

•Bearing warn out of misaligned

•Misaligned of pump

•Check lubricating oil system (pr.>2.5kg/cm)

•Examine bearings

•Check the alignment

Thank You