Power Piping Displacement Measurement

Presentation on Sharing of Research Project Seminar TNBR QATS: Involve to Solve April 2017

Power Piping Displacement Measurement & Monitoring System at Power Plant

Mohd Hafiz Bin Abdul Ghaffar Researcher Materials Engineering Group TNB Research

Introduction • ASME B31.1 Chapter VII – Operation and Maintenance, Section 144 CPS WALKDOWNS [1] • “The Operating Company shall evaluate the effects of unexpected piping position changes, significant vibrations, and malfunctioning supports on the piping system’s integrity and safety”. • “Significant displacement variations from the expected design displacements shall be considered to assess the piping system’s integrity”

2 Copyright © 2017 TNB Research

Background

Suspended beam is not balanced, slanted to the other side

Fig.1. Damaged Pipe Hanger

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Power piping system is one of the critical components that need attention as it operates at elevated temperature and high pressure

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Weight, thermal expansion of the pipe generates enormous force and stress in the system

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Pipe hangers/supports are to minimize & maintain the system stresses to be within the allowable limit & allow sufficient movement [1].

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Sudden change in operation load, upset & transient event, causes dramatic pipe displacement can lead performance degradation & malfunction, further induce high stress on piping system [2].

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One way to prevent pipe hanger malfunction is to have continuous monitoring of pipe displacement.

Fig. 2. Pipe crack near elbow.


Background (2) •

The addition of mandatory Chapter VII to ASME B31.1 communicated to the industry the need to perform pipe support walkdown at hot and cold condition [3], read and record piping system displacements as part of the piping and pipe support maintenance program.

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Periodic monitoring and walk down has limitation in capturing pipe position:  visual inspections are only spot check- pipe position is recorded only at the time of inspection.  horizontal movement of the pipe remains unknown  Reading data from distance due to inaccessible pipe hanger cause inaccurate hanger reading & lead to incorrect pipe movement

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Gaining access to the hard-to-reach hangers, reading data from a distance, necessitate other technique of pipe displacement survey/monitoring to be used

Fig.4. Pipe hanger reading during hanger walk down

Fig.5. Inaccessible pipe hanger during walk down


Overview of the Pipe Displacement Monitoring System Piping Site

Plant

PLUMBER Server

Transducers

Engineers’ Room

Clamp at fixed structure: beam

Clamp at pipe hanger clamp

Fig. 6. 3DDMS transducer

Turbine Hall

Monitoring

Fig. 7. Schematic diagram of 3DDMS and PLUMBER system

• Transducers installed on piping system (at site). • PLUMBER (system server) placed near turbine hall. 5 Copyright © 2017 TNB Research

Benefit The benefit is aspired from the continuous pipe movement capture and monitoring, early issues identifying Capture Pipe Movement: Magnitude & Direction

3DDMS on Power Piping System

Continuous Pipe Movement Monitoring

Benefits •

• •

Detection of Abnormality

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Sudden, fluctuated abnormal movement due to transient/upset event can be captured, aids in identifying issues early Significant displacement variations from the expected design displacement can be detected As a means to support identification of critical locations for inspection & assessment Can be part of the pipe support program development


Case Study: Power Piping Displacement Monitoring 5&6

2 T6 T8

T5 1

T1

T3

T2

T7

T4

3&4

7

• Transducer locations on Main Steam pipe Copyright © 2017 TNB Research

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7

Case Study: Power Piping Displacement Monitoring

Displacement trending

Temperature trending PLUMBER Piping 3D Visual

• Trend View exhibits pipe movement trending for specified period of time including history trending • Pipe design movement & pipe movement limits can be integrated in the trending for reference & monitoring purpose 8 Copyright © 2017 TNB Research

Case Study: Power Piping Displacement Monitoring 6

8

5 15

5

37

37

7

y

z August 2016 to December 2016

x

22 52

Pipe displacement in x- (blue), y- (red) and z-axis (green)

• 3DDMS (Transducer) data showed unsynchronized pipe movement in y- and z-axis of 3DDMS Location 7 & 8. • Pipe actual movement difference has exceeded the design movement difference. • Unsynchronized movement in y- and z-axis of north & south pipe could create high stress on weldment of H-joint. 9

Copyright © 2017 TNB Research

Visual Inspection

MSP (Left)

CRH

• MSP cladding is in contact with beam structure • Figure shows beam structure is penetrated into MSP cladding (near to 3DDMS location 8), this could probably disturb pipe movement 10 Copyright © 2017 TNB Research

Conclusion • Hanger survey & piping inspection are key to monitoring power piping system as pipe support/hanger malfunction is the first sign of trouble, cause elevated stress, the displacement measurement system can greatly contribute to the piping system safety and reliability

• The displacement measurement system is able to continuously capture and monitor pipe displacement during normal operation and transient, aids in identifying issue • Significant displacement variations from the expected design displacement can be detected and considered in assessment of piping system integrity as recommended in ASME B31.1 • As a means to support identification of critical locations for piping inspection & assessment 11 Copyright © 2017 TNB Research

THANK YOU Prepared by : [Mohd Hafiz Bin Abdul Ghaffar]

Office address: TNB Research Sdn. Bhd. No. 1, Lorong Air Hitam Kawasan Institusi Penyelidikan 43000 Kajang, Selangor Darul Ehsan MALAYSIA Tel: +603-8922 5000 Fax: +603-8926 8828/9 Email: [email protected] / Website: www.tnbr.com.my


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