ACOUSTEAM HPT HPC. System for Leakage Detection on Boiler in Power Plant AV107 SI270 ELECTRONIC NEWS

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1 System for Leakage Detection on Boiler in Power Plant ACOUSTEAM HPC HPT AV107 SI270

2 The Company History ELECTRONIC NEWS is an Italian medium-size company founded in 1978 near Como lake in the north of Italy. In the first 10 years of activities Electronic News was focused in engineering and production of Heating Control System, Thermal Control System and Electronic Instruments customized for customer s needs. In the 1990 ELECTRONIC NEWS started to provide turnkey solutions for heating-control / fire-prevention in Oil & Gas and Power Generation markets. In the 2008 ELECTRONIC NEWS founds Fibersens company in collaboration with Sant Anna Photonic Institute. Fibersens is a spin-off company for developments of fiber optic sensing. Electronic News today is a System Integrator able to provide many different turnkey solutions as well to engineer and realize customized electronic instruments and sensors. ELECTRONIC NEWS is certified by UNI EN ISO 9001:2000 and guarantee high quality in all internal processes, as certified by CSICERT. All our electronic instruments are certified as ATEX products.

3 Acoustic System for Leakage Detection on Boiler in Power Plant The heating process of water that feeds the boiler of a big power plant has a strategic importance because its e!ciency is directly related to the general performance of the plant. For this reason it s very important to maintain under control and monitoring 24/24 a day all the components, like steam-pipes, that are involved in this heating-process. A potential break of these steam-pipes will generate big losses of the performance of the boiler and consequent of the entire power plant. Breaks are generally due to erosion/corrosion processing, wear over time, creep, oxidation, over-heating processes, etc that usually take place on the external surface of the pipes up to create an holes and breaks. Violent loss of hot-water as well as hot-saturated-steam from one pipe, could generate a chain-e"ect, breaking other pipes placed around the first one. Moreover this ripple-e"ect could involve in breaking other bigger structure such as manifolds and heat-exchangers, creating a dangerous situation for workers. For these reasons it s really important to be able to detect pipes-breaking process as soon as it happens at the first pipe. Our experience has shown us that a micro-cracking on a pipe containing hotsteam, saturated steam or other hot elements, generate a specific sound that is absolutely di"erent by other sounds generated by other processes such as: combustion chamber sound, water flow sound, blowers. So we developed a system able to detect di"erent sounds emission and so able to understand which elements are involved in breaks. The sound detected is converted into analogical signals by an electronic equipment we developed having di"erent alarms threshold.

4 PHISICAL PRINCIPLE OF ACOUSTIC EMISSION When a pressured fluid or steam go through a break into a place having a lowest level of pressure, generates turbulence and transform part of its energy in acoustic energy. We can explain this process with the following formula: ACOUSTIC ENERGY = K p 0 U 8 A 0-5 d 2 P o = Flow Density U = Speed A = Sound Speed in the Fluid d = Diameter of the Break K = Costant Losses from pipes in power plants are usually constituted by hot-steam or hotwater and they happen with a critical flow, for this reason we can use the formula: ACOUSTIC ENERGY = K p 0 A 0 3 d 2 = costant x d 2 The Acoustic Energy generated is directly proportional only to the size of the break, so, we are able to understand the evolution of breaks (become bigger and bigger) listening to the evolution of sound emission. Acoustic Energy propagates all around going inside other iron structure and generating a wide range of frequencies. Gustav Kirchhoff s law of thermal radiation refers to wavelength-specific radial emission and absorptionby a material body. The signal associated by a break is almost stationary signal having a wide frequencies range, for this reason, to be easily detected we can use a specific value, RMS: RMS = [1/T T 0! S 2 (t) dt ] 1/2 Moreover a loss cannot be expressed only by a flow-rate or a delta-pressure!p but also (and better) in leakage rate Qv x!p expressed in BAR x 1/4 hr. It follows the following relationship: : RMS (db) = m log Ø + b dove Ø = "p x Q v - b is a coefficient related to frequencies range and can be assumed as detection-coefficient - m is a dependent parameter by geometry of the break.

5 Acoustic System for Leakage Detection of a Single Component Model Rap-C Working Prnciple Piezoelectric transducer detects the value of acoustic energy transmitted through metal, in the frequencies range between 0.1 MHz and 1 MHz. It must be installed on the external surface of the object to be monitored through a specific waveguide welded to the same object. The terminal part of waveguide is fixed to the transducer s case to create an appropriate link between waveguide and transducer. Transducer s case dampens vibrations, protects the transducer and makes it possible to install the sensor on any type of surface. The standard sound-level available during standard process increases immediately when a break happens and this variation is evident in the range MHz. To detect the heat-exchangers one single transducer is enough and must be installed on the flange near tube-sheet; on collectors of boiler that are usually very long it s better to install two lines of transducers; for piping detection every time must be selected a customized installation having different lay-out and number of transducers, to do it you need experience and we can assist you in this customer-service. AV107 for System HPC Transducer e Waveguide Wall manifold

6 Acoustic System for Leakage Detection of Area Model Rap-V Working Prnciple The Working Principle is almost similar to RAP-C and is based on detection of the sound-level-emission due to flow of an hot-steam or hot-water through a break on pipes or other elements compared with background-noise. Unlike RAP-C System the Transducers of RAP-V System detects sounds emission from combustion gas expansion. For this reason they have a higher sensitivity. SI270 for System HPT

7 A Standard Lay-out of Installation is: Two-wire cable MAS128AS Serial Cable - under the last line of burners - above last line of burners; - above combustion chamber - area of super-heaters of high temperature; - area of super-heaters of the recirculation; - manifolds area (phenthouse) with this lay-out it s possible to detect a break of pipes under 10 meters range. For a correct installation of the Transducers it s necessary to fix them at the final part of waveguide folded at 90 with an air-inlet system for cooling and for periodical cleaning activities. It s also possible to change the transducers while the boiler is working. Both sensors can be connected to our electronic device (one instrument can collect signal from maximum 4 sensors) or can be collected by a bigger acquisition and processing system, able to generate different alarms and having an selfdiagnostic elaboration. We provide different software solution, able to show in the field as well as in a work-station located in a remote control room, all the data collected from the fields into graphics view showing real-time trends; in the while time the software storage all the data in its historical database for future studies and analysis.

8 Standard Lay-out RAP-C and RAP-V Systems are composed by : Two-wire cable MAS128AS Serial Cable - Special sensor for acoustic detection with impedance adapter to connect it directly to the remote electronic device; - Low noise shielded line, meters long, depending on the value of the signal and depending to the background noise, that transport our signal to the next electronic device for signal treatment. - Multi-channel on site device, able to collect max 4 sensors, able to elaborate signals detected and to generate alarms. It can be fixed in a standard rack 19 (prepared for 8 devices max); - Multi-channel-system for acquisition and elaboration, MAS128, to connect max 128 different sensors; - Electric Cabinet containing MAS 128, available with different IP levels. Able to be installed in proximity of the monitored area, in hazardous area and in any case directly on the field. - Serial communication line for data transferring from MAS128 to super-visionsystem, located in a remote control room; - Dedicated PC located in the remote control room for data elaborating and storage and for operational activities.

9 Tipica Applicazione del Sistema di Rilevazione Acustica MAS128AS ACOUSTEAM HPC SCAMBIATORI DI CALORE dove normalmente viene installato un solo Trasduttore in corrispondenza della Piastra Tubiera COLLETTORE DI CALDAIA che essendo caratterizzati dal notevole sviluppo in lunghezza di norma vengono installati 3 Trasduttori posizionati sulla parte superiore e posizionati all inizio nella parte mediana e alla fine del collettore PIPING dove in base alla lunghezza e alla conformazione delle linee viene stabilito di volta in volta il numero e la posizione dei Trasduttori da installare Scatola di Protezione del Trasduttore Sensore AV107 per Sistema HPC Guida Sonda Componente monitorato

10 Tipiche Applicazioni del Sistema di Rilevazione Acustica ACOUSTEAM HPT Rilevamento della rottura dei tubi costituenti Fasci Tubieri che compongono la parete di Caldaia. Di norma, per una corretta sorveglianza di una Caldaia di un impianto di produzione energia, la disposizione tipica dei trasduttori generalmente è la seguente: Sotto la prima fila dei Bruciatori Sopra l ultima fila dei Bruciatori Nella parte superiore della Camera di Combustione Area dei Surriscaldatori di alta Temperatura Area dei Surriscaldatori del Ricircolo Area dei Collettori Con questa disposizione si ha la possibilità di tenere sotto controllo tutti i Fasci Tubieri della Caldaia. La corretta installazione dei Trasduttori prevede il loro fissaggio all estremità di una guida d onda piegata a 90 dotata di un Sistema per l immissione di aria utilizzata per il raffreddamento del Trasduttore e di sbarramento per consentire le operazioni periodiche di pulizia e l eventuale sostituzione dei Sensori con l Impianto in servizio. LEGENDA - Sensore Sibilo Sensore RAF Lato sinistro Fronte Lato destro Retro 8 Piano 7 Piano 6 Piano 5 Piano 4 Piano 3 Piano 2 Piano Quota 6

11 Sistema di Supervisione ed Elaborazione a Controllo Distribuito realizzato su piattaforma Personal Computer, espandibile nel tempo e capace di generare informazioni dal processo in tempo reale. Il Sistema utilizza la comunicazione RS485 con protocollo MOD-BUS-RTU che garantisce alta velocità di trasmissione e immunità ai disturbi. VANTAGGI L impiego dei Sistemi di Rilevazione Acustica consente di individuare le perdite al loro insorgere e quindi permettere di pianificare l intervento di r i p a r a z i o n e o s o s t i t u z i o n e d e l componente interessato dalla rottura, in modo tale da evitare l e-voluzione del danno che potrebbe causare la fermata dell Impianto per lunghi periodi. In questi impieghi il Sistema di Rilevazione Acustica segnala il mancato funzionamento di una o più trombe evitando così l accumulo di cenere che potrebbe causare problemi alla funzionalità dell Impianto e di emissione in atmosfera di particelle nocive per l ambiente. I Sistemi di Rilevazione Acustica trovano applicazione anche sugli Impianti (esempio Denitrificatori/Desolforatori) laddove per evitare l accumulo di cenere vengono utilizzati apparati ad emissione acustica trombe.

12 Markets Oil & Gas Power Generation Tunnels Smart Grid Worldwide Europe Middle East South America IRAN DUBAI BRASILE ARGENTINA COLOMBIA DANIMARCA Main Products Thermal Control System Fire Prevention System Fiber Optic Sensors Continuous Thermocouple Linear Sensor Acoustic Sensor Customized Electronic Instruments Industrial Automation for Temperatures Monitoring in Industrial Processes Special Thermocouple Instruments Division Lenno (CO) - Italy Turnkey Solutions Division Cernobbio (CO) - Italy Installation and Service Division Vado Ligure (SV) - Italy FIBERSENS R&D in Fiber Optic Sensing Pisa - Italy ELECTRONIC NEWS s.r.l. Via Regina, Lenno (Como) Italy) tel Fax División de Sistemas Viale Matteotti, Cernobbio (Como) Italy) tel Fax info.system@elenews.it