Spark Detection and Extinguishing System

Spark Detection – markets Initiative from Finnish insurance companies  Need for technically competitive and cost efficient Spark Detection System ATEX (94/9/EY, 1992/92/EY) directives  Regarding potentially explosive atmospheres and machines and devices used in them.  State council statute obligates employers to evaluate possible risks regarding dust explosions and in case of risk move to corrective actions

Spark Detection – Dust explosion Dust explosion is a fast burning reaction. Dust explosion moves forward from the ignition point spherically lifting pressure and thus causing damage to constructions Dust explosion is possible, when there is enough fine material mixed with air and a spark or high enough temperature Material can be almost anything as long as it is fine enough.

Spark Detection – What it does The purpose of the system is to extinguish the detected sparks before they cause a dust fire or a dust explosion. Following systems can be protected with the system:  Saw dust outlet systems  Dust outlet systems  Grinders and pellet burners Spark detection and extinguishing system is not used for protecting rooms

Spark Detection – markets Applications in mechanical wood processing industry and more accurately:  sawdust outlet pipes, conveyors etc Potential customers:  carpenters, sawmills, planing mills, furniture factories, schools, paper mills…

Spark Detection – Principle Extinguishing unit Spark detectors Saw dust outlet pipe Air flow 1. Spark detectors and extinguishing unit  Basic system includes only two detectors and an extinguishing unit  Extinguishing unit is a part of the Spark detection system

Spark Detection – Principle Extinguishing unit Spark detectors Saw dust outlet pipe Air flow Panel 2. Detectors, extinguishing unit and panel  By adding a panel to the system, it is possible to –get info of the possible alarms (siren and beacon) –shut down machines in the production process –test the system

Spark Detection – Principle Extinguishing unit Spark detectors Saw dust outlet pipe Air flow Panel FX 3NET 3. Detectors, extinguishing unit, panel and FX 3NET  Spark detection system panel can be connected to a control computer via ModBus-fieldbus. This enables for example the monitoring of alarm log

Spark Detection – connection to fire alarm panel The system is usually used as an individual system The system can be connected to a fire alarm panel, if:  the alarm needs to be transmitted to the fire brigade  the alarm information needs to be tranferred to the fire alarm panel locally

Spark Detection - System The system consists of three different main blocks: Detection  Detectors  Test lamp Control  Control Panel  Alarm devices (sounder and beacon)  Signal router Extinguishing  Extinguishing unit  Pressure boost unit

Spark Detection – System Components The System consists of three main blocks  Spark detector - Detects the sparks and controls the extinguishing unit - Transmits the info about the extinguishing events to the panel - Measure area UV - IR  Fulfils the requirements of: EN50081, EN50082, EN , EN54- 1, IEC /2

Spark Detection – System Components  Spark detection panel - Works as a human interface - Shuts down machines in alarm state - Measures device temperatures - Communicates with control computer via ModBus (option) - System can be connected to Esmi FX Fire panel Integration

Spark Detection – System Components  Extinguishing unit –Extinguishes sparks with a fine water screen. Extinguishing unit is fault monitored by a flow switch and also by the panel. –Extinguishing unit is used in saw dust outlets under 450mm diameter –The self cleaning unit is designed so that the particles flying in the pipe will not damage it Extinguishing unit

Spark Detection – System Components  Extinguishing unit –Extinguishes sparks with a fine water screen. Extinguishing unit is fault monitored by a flow switch and also by the panel. –Extinguishing unit is used in saw dust outlets over 450mm diameter –The self cleaning unit is designed so that the particles flying in the pipe will not damage it Extinguishing unit

Spark Detection – System Components  Pressure booster (part of the extinguishing unit) –Requirements for the water and electric suplies: Water pipe min. DN28 and flow 100l/min/nozzle Motor voltage 3*400V and current 5A Pressure booster consists of a water pump and diaphragm pressure tank

Spark Detection – Installation requirements Pressure booster  Electrical connections has to be done by an electrician  Pipework has to be done by a plumber Planning or installing of Spark detection systems in Finland does not require same kind of qualifications as in case of sprinkler systems. Spark detection systems are not EN standardised. Planning and installations should done according to European Insurance Committee: CEA Specifications for spark detection, spark extinguishing and spark diversion systems – Planning and Installation

Spark Detection – System Components

120 Spark detectors and AN6400 Panel

Spark Detection – System Components Extinguishing unit

Spark Detection – System Components Pressure booster

Spark Detection – System Components Alarm devices, siren and beacon

Spark Detection – System Components Temperature monitoring

Spark Detection – System Components Expansion options

Spark Detection – System planning System response time from detection to extinguishing is <100ms Extinguisher units are installed in direction of air flow after the detectors Detector Extinguishing unit

Spark Detection – System planning The distance between extinguishing unit and detector is calculated with the following formula d= F x 2D, where d = min. installation distance F = air flow speed (typ m/s) D = System delay (<100ms) Calculated with 25 m/s air flow d = 5m Manufacturers ”thumb rule” d = 7m d

Spark Detection – System planning The bigger the diameter of the pipe is, the more water has to be injected into it. The needed water amount can be calculated with the following formula: Q = F x A x B, where Q = water amount needed l/s F = air flow speed (typ m/s) A = pipe cross area π x r² B = constant 0,2l/m³ (0.2 litres water / 1m³ air)

Spark Detection – extinguishing unit / nozzle Nozzle in the pipe on the left In this picture there is a nozzle designed for 400 mm pipe in a 700 mm pipe

Spark Detection – Installation pictures Detectors and a test lamp Detectors are installed facing each other on the sides of the saw dust outlet pipe. This way maximum visibility of the detectors is achieved. Detectors must not be installed in the bottom of the pipe. Danger of coverage. Detectors must not be installed just after a corner. Danger of breakage. Signal router

Spark Detection – Installation pictures Detectors and Signal router Detectors Panel Pressure Booster Signal router Extinguishing unit Sounder and Beacon

Smallest detector in the market  Very fast response time (1ms) Fastest System response time on the market Detector and extinguisher can be installed near to each other thanks to fast System response time  - > less extinguishers outdoors -> less separate extinguisher warmers  Minimized extinguishing water -> less problems with filters User friendly, easy user interface Cost effective compared to earlier systems on the market Spark Detection – Advantages