WORN VENT

ALTERED SET POINT

VENT MALFUNCTION

HIGH WATER LEVEL

TUBE LEAKES

IMPROPER SETTING

HEADER PARTITION LEAKS

NONCONDENSIBLE GASES IN SHELL SIDE

EXCESSIVE TUBE BUNDLE PRESSURE DROP

EXCESSIVE NUMBER OF TUBES PLUGGED

TUBES FOULED INTERNALLY

HIGH DRAIN COOLER APPROACH TEMPERATURE (DCA)

DRAIN COOLER INLET NOT SUBMERGED

LOW WATER LEVEL

IMPROPER SETTING

EXCESSIVE FW HEATER DRAIN BYPASS

IMPROPER SETTING

BYPASS VALVE LEFT OPEN

BYPASS VALVE MALFUNCTION

BYPASS VALVE LEAKS

EXCESSIVE TUBE BUNDLE PRESSURE DROP

EXCESSIVE NUMBER OF TUBES PLUGGED

TUBES FOULED INTERNALLY

FEEDWATER HEATER BYPASSED

FW HEATER BYPASS VALVE LEAKS

CONTENTS

1.0Introduction

2.0Objective and Scope

3.0Reference

4.0Design Data

5.0Test Instrumentation

6.0Instrument Installation

7.0Test Instructions

8.0Test Frequency and Duration

9.0Personnel Needed

10.0Test Setup

11.0Duration of Test Run and Frequency of Readings

12.0Definitions

13.0Calculation

14.0Report

1.0 Introduction

A boiler feed pump is a component designed to feed water to the boiler at the rated conditions of pressure, temperature and flow. By plotting efficiency, capacity, total head, balance drum leak off and pump input power on control charts, showing historical and expected data, the current condition of the pump can be assessed. The maintenance requirements can be planned based on the gaps, adverse trends and sudden changes.

2.0 Objective and Scope

The scope is limited to boiler feed pumps.

The objectives of the boiler feed pump test is to establish rules for conducting tests on pumps to determine under specified conditions one or more of the following parameters:

2.1Total Head Produced by the Pump.

2.2The Capacity or Rate of Flow.

2.3Power Input to the Pump.

2.4Train Efficiency.

2.5Balancing Drum Leakoff Flow

3.0Reference

Based on ASME performance test code PTC 8.2 ,1990 on Centrifugal Pumps.

4.0Design Data

BFP design data as per Anneuxre – I

5.0Test Instrumentation

The parameters required to be monitored to conduct the boiler feed pump performance test consists of temperature, pressure and differential pressure.

5.1Test Instruments and Measurement Required

The No. of instruments required per BFP is as follows:

In addition to the above power measurement is to be carried out with high accuracy power meter, and motor and pump speed with high accuracy tachometer or stroboscope.

5.2Instrument Accuracy Requirement

The instrumentation selected for the test shall be capable of achieving the following measurement accuracies:

5.3Instrument Calibration

The instruments used for the test will be calibrated once in two years. The calibration records of these instruments will be maintained as permanent records and reference to current calibration will be made in the report.

5.4The performance test data from test instruments will be recorded using sample format as given in Annexure - II.

5.5Measurement required from station instruments are given in Annexure - III This format will be used for collecting station measurement during the performance test.

5.6Data required from DAS are given in Annexure - IV. These data will be used for comparison of DAS data with test instrument data.

6.0Instrument Installation

6.1Pressure Measurement

Pressure instruments which operate above atmospheric pressure require all pressure sensing lines to be blown down prior to installing the instrument, and the instrument vented after it is pressurized, if possible. The pressure sensing lines should be plumbed with a continuous downward slope from the pressure tap to the sensor to prevent pockets of steam or air. The appropriate waterleg measurements for each pressure instrument should be made and entered as part of the data for each instrument.

6.2Temperature Measurement

All thermowells should be cleaned and the bottoms polished prior to installing the temperature sensors. All temperature sensors should be installed in a manner to ensure they make good contact with the bottom of the well and secured to ensure they are held firmly against the bottom during use. All temperature sensors whose shafts extend past the thermowells should be insulated.

6.3Speed Measurement

The speed shall be measured by any reliable revolution counter, accurately calibrated tachometer or a portable stroboscope.

6.4Data Acquisition System (DAS) and Processor and Analyzer System

It is preferable to use a portable DAS and processor and analyzer for performance testing. This will ease the testing process and provide on line monitoring of test data and results. It will also help in tracking the process stability and thereby reduce the uncertainty level of results.

6.4.1Portable Data Collection Unit

One/two portable units may be used to cover the inputs at the test location. Each DAS unit should have a minimum of 16 universal inputs as given below:

a)PT 100, 4 Wire RTD

b)4-20 mA, 2 Wire Transmitter output with a built-in facility to power the Transmitter.

6.4.2Portable Processor and Analyzer Unit

•IBM compatible portable machine with a Pentium processor.

•Graphic display compatibility.

•32 megabytes of RAM

•Windows 95 with Microsoft Excel version 7.0

•IDAAS and DALITE Software as analyzer.

6.4.3Installation

The following precautions should be taken during installation of the data collection unit with the portable processor.

•Identify the location of power supply

•List out the inputs with respect to Channel No.

•Review the status of fuses.

•Tag input leads at both ends by masking tape, etc.

•Connect the inputs as per channel listing. Cascade the output from one data collection unit to other, connect network cable from data collection to the interface unit/portable processor unit.

•The network cable should be laid away from movement areas, without obstructing the plant equipment and 2-3 meters above the floor level.

•Ensure the tightness of all connections.

•Charge the power supply and check for the channel’s functionality.

•Verify the system is networking.

•Carry out a test run to scan and ensure proper system functioning.

7.0Test Instructions

7.1Unit should be in operation at normal full load in steady state condition.

7.2Ensure that the recirculation valve is closed.

7.3Feed water flow to be maintained constant at the required level for the duration of the test run. Variations in feedwater flow shall not exceed

+/- 2%.

7.4First test run is conducted at normal feed flow. Subsequently other test runs are conducted by varying the feed flow at levels above and below normal flow.

7.6Speed measurement is carried out during the duration of the test run using tachometer or portable stroboscope.

8.0Test Frequency and Duration

8.1Routine testing every 12 months

8.2Special requests for various reasons.

8.3Each run shall continue for a period sufficiently long to ensure accurate and consistent results. With the online computational software described in Section 6.4 each run duration should be of 20 minutes after attaining steady state condition.

9.0 Personnel Needed

The test requires two persons, for test set-up and for taking data at site and at control room.

10.0Test Setup

10.1First notify the Shift Incharge and Unit Controller about the program for conducting the test and inform about test equipment/instrument being installed.

10.2Install the Pressure transmitters and RTDs (as per Section 6.1 & 6.2) at the locations described as per Section 5.1

10.3The output of transmitters and RTDs to be connected to data collection unit and this in turn to be connected to data processing unit as indicated in Section No. 6.4

11.0Duration of Test Run and Frequency of Readings

11.1 CASE I - Testing by Using DAS and Processor & Analyzer System

11.1.1Test duration: Each test run should be conducted for a period of 15-20 minutes, after achieving minimum uncertainty.

11.1.2Frequency of test data: After achieving the point of minimum uncertainty as shown by the data processor, the test may be commenced and the readings taken at a frequency as given below:

•test instrument readings by data processor as per normal scan rate.

•manual readings from control room at an interval of 5 minutes.

11.2CASE II - Testing by manual data collection

11.2.1Test Duration: Each test run should be conducted for a period of 30-45 minutes after achieving stable parameters.

11.2.2Frequency of Test Data: All readings should be taken at 5 minute intervals.

11.3Data Verification

During the course of testing compare the historical performance data showing expected value of the critical measurements as appropriate. This will help in assessing the error, if any, in data being collected.

12.0Definitions

Refer to Annexure - V

13.0Calculation

Refer to Annexure - VI

14.0Report

The report should include a narrative describing any unusual findings as well as the following:

14.1Executive Summary

14.2Objective

14.3Scope

14.4Background

14.5Test Methodology

14.6Results

14.7Discussions

14.8Conclusions

14.9Recommendations

14.10Acknowledgment

14.11References

14.12Complete set of Appendices

14.12.1Analysis and Results

14.12.2Test Data