| In any type of production facility, fire | | | | Important functions and all alarms are |
| control encompasses a wide range of equipment | | | | displayed clearly. The buttons on the keypad |
| or systems from building sprinklers to plant | | | | light up and provide visual |
| site fire departments. A spark detection | | | | information.Integrated MemoryThousands of |
| extinguishing system must be thought of as | | | | events are stored so that important |
| part of a plant's overall security and safety | | | | information is not lost. This enables |
| network. Just as a residential alarm system | | | | analysis of alarms at any time: |
| provides protection to a homeowner, a spark | | | | |
| detection system provides preventive | | | | |
| protection against potential loss of human | | | | |
| life, production facilities, equipment and | | | | When exactly did the spark stream happen? |
| costly downtime.Where do Spark Streams | | | | |
| appear?Spark streams in dust collection | | | | How heavy was the spark stream? |
| systems are a very common danger. They are | | | | |
| not easily detected and this means that they | | | | How long did the extinguishment action last? |
| may exist but are not known! Consequently, | | | | |
| attention is paid to a spark stream only when | | | | |
| it is too late, namely when there has been an | | | | Where exactly did the spark stream appear? |
| explosion or a fire.When working with | | | | |
| industrial machinery, sparks are created very | | | | When was the system out of action? |
| quickly. A blunt tool, a damaged bearing in | | | | |
| the fan, an overheated motor or foreign body | | | | When and where did troubles appear? |
| within the material can be the cause.Sparks | | | | |
| are a constant danger in those factories | | | | |
| where combustible materials are being worked, | | | | |
| exhausted, transported, filtered or dried.The | | | | The answers to these questions can be found |
| damage statistics provided by the insurance | | | | in the memory of the control console and the |
| companies point out that filters, dust | | | | danger spots can be identified very quickly. |
| collection bins, silos and even complete | | | | The display field not only shows the alarm |
| production lines are the areas of a plant at | | | | itself, but also informs about the measures |
| greatest risk. Foreign bodies in the | | | | that have been taken. The memory content can |
| conveyed material, defective parts of the | | | | be printed out at any time to an external or |
| production machinery, friction processes as | | | | internal printer.Automatic Function Checks To |
| well as electrical sparks are all identified | | | | ensure cables are functioning correctly, they |
| as fire generating. Here are the main danger | | | | are constantly checked for open and short |
| areas known: | | | | circuit conditions. In addition, spark |
| | | | sensor function tests are performed regularly |
| | | | and automatically. Extinguishing device |
| | | | function tests can be performed manually from |
| Fiber and Particle Board Industry: The fiber | | | | the control console.The Spark DetectorThe |
| and particle board processing as well as the | | | | most important component of a spark detection |
| further processing of the panels by sawing | | | | and extinguishment system is the spark |
| and sanding | | | | detector. To suit the different and often |
| | | | very severe applications, three different |
| Wood-Working Factories: Working of materials | | | | types of sensors are used. All three sensor |
| by means of saws, planers, mortisers, | | | | types have highly sensitive electronics which |
| hoggers, sanders and other wood working | | | | detect even the smallest of glowing |
| machines | | | | particles.Spark Detector FM 1/8The FM 1/8 |
| | | | detector features reliable function even in |
| Chemical Industry: Pneumatic conveyors of | | | | very dense material flow or when a dust layer |
| dusts and powders | | | | covers the optical element. It can be used |
| | | | at material temperatures up to 149°F |
| Foodstuff Industry: e.g. Coffee roasting, | | | | (65°C), which corresponds to a temperature |
| tobacco processing and pneumatic conveying of | | | | range of extraction systems for woodworking |
| powders | | | | machines like saws, planers, sanding |
| | | | machines, etc.Spark Detector FM 3/8The FM 3/8 |
| | | | detector is used in applications with |
| | | | operating temperatures above 149°F |
| Why is it so Dangerous?The spark itself is | | | | (65°C) as can appear in drying processes, |
| not dangerous. Here's why: For the creation | | | | for example. Spark radiation is carried |
| of fires or explosions there must be three | | | | through fiber optic cables to the |
| elements that are combined simultaneously: a | | | | detector.Daylight Spark Detector DLD 1/8For |
| combustible material, oxygen and an ignition | | | | the most reliable detection of glowing or hot |
| source. Removal of one of the elements will | | | | particles, no ambient light can be present at |
| prevent a fire or explosion.In today's | | | | the sensor location. However, where an |
| production plants, we have to cope with all | | | | absolute dark surrounding cannot be |
| elements that can lead to fire damage or | | | | guaranteed, sensors that aren't sensitive to |
| cause an explosion. Extraction systems and | | | | daylight or ambient light are used. These |
| pneumatic conveyors increase the danger of | | | | sensors operate only in the infrared spectrum |
| fire. Once sparks and glowing embers are | | | | of light so they can be installed at open |
| created, the pneumatic extraction system | | | | transfer points or on conveyor belts.Thermo |
| conveys this danger very quickly to other | | | | Detector TM 1/8The thermo sensor TM 1/8 is |
| subsequent areas of the plant. The danger is | | | | used for the additional inspection of large |
| when two of the three elements necessary for | | | | areas, like filter and silo systems. Its |
| the creation of fires and explosions are | | | | task is to monitor these areas for |
| transported, namely: air and ignition sources | | | | self-ignition of the material being conveyed |
| (sparks).When this conveyed danger meets | | | | or stored.The Extinguishing DeviceWater is |
| combustible materials (filter cloth, | | | | the best extinguishing agent. Its excellent |
| deposited and combustible dust in a separator | | | | extinguishing efficiency mainly results from |
| or silo) it becomes more and more likely that | | | | the high ability of heat absorption. For |
| a reaction will happen.Environmental | | | | this reason it has a strong cooling effect |
| protection measures regarding dust emissions | | | | that prevents re-ignition of the combustible |
| and tightened regulations for air pollution | | | | materials.To obtain an optimal extinguishing |
| led to an increased use of filter systems, | | | | efficiency, the area covered by the water |
| but the danger of dust explosions has not | | | | must be kept as big as possible. This is |
| been reduced. In the process of drying, the | | | | accomplished by a fine atomization of the |
| dryer capacities have been steadily increased | | | | water. Atomization is achieved through a |
| so that prevention of fires in these systems | | | | special nozzle and sufficient operating water |
| has become more important than ever.What | | | | pressure. With high atomization, the amount |
| happens after a filter fire? Environmental | | | | of extinguishing water can be minimized so |
| regulations prohibit plant operation without | | | | that filter elements are not damaged by an |
| the filter system. The plant will not only | | | | excessive amount of water. This allows |
| have the cost of repairing the damaged filter | | | | production to continue while extinguishing |
| system caused by fire but also absorb the | | | | takes place.The operating pressure of the |
| extremely high loss of a production | | | | extinguishing device should be at least 60 |
| shutdown.According to individual reports, | | | | PSI at a flow rate of 24 GPM per nozzle. If |
| these production losses can exceed the damage | | | | this pressure is not available, a |
| costs many times over.The risk of fire can be | | | | pressure-increasing unit must be used. |
| efficiently reduced or eliminated by means of | | | | Because extinguishing nozzles are spring |
| modern spark detection and extinguishment | | | | loaded and flush-mounted, they are |
| systems.Returned air to the plant also | | | | contamination-free and do not obstruct the |
| requires spark detection and extinguishment | | | | material flow.Not all extraction ducts of the |
| systems. Due to the high amount of material | | | | plant are located inside the production |
| now collected in the dust filter systems, in | | | | building. Sometimes the extinguishing |
| certain circumstances clean air is allowed to | | | | devices are required to be installed outside. |
| be returned to the production buildings. | | | | Heat tape and insulating material is used to |
| Enormous savings in heating energy are | | | | protect water pipes and extinguishing devices |
| achieved in this way. A filter fire, | | | | from freezing in areas exposed to frost. |
| however, could quickly be transferred to the | | | | Special insulating bags are available for the |
| production area with devastating | | | | extinguishing devices.Alternatives to |
| consequences.To protect such a system, all | | | | Extinguishing MeansIn some production and |
| extraction ducts as well as the conveying | | | | processing systems, water cannot be used as |
| duct to the material storage should be | | | | an extinguishing means because it would have |
| equipped with spark detection and | | | | too much influence on the subsequent process. |
| extinguishment systems.How can you take | | | | This is particularly true for the food |
| Preventive Measures?Protection can be | | | | industry where extremely high accuracy in |
| achieved by installing a modern spark | | | | respect to the material's moisture must be |
| detection and extinguishment system. The | | | | observed. There are also other industries |
| sensors detect sparks and glowing embers | | | | where water is not allowed as an |
| immediately after their creation. Upon | | | | extinguishing agent. There are alternatives: |
| detection and evaluation, countermeasures are | | | | Diversion gates, shut-off gates, fire traps |
| induced immediately in order to eliminate the | | | | and even the actuation of a C02 or other |
| causes of a fire or an explosion.Let's | | | | inert gas system.Diversion Gates, Shut-off |
| compare fire extinguishment systems with | | | | Gates, Fire Traps.In these industries, |
| spark detection and extinguishment systems. | | | | diversion gates to abort the material flow or |
| Fire extinguishing systems combat fire after | | | | shut-off gates and fire traps to stop the |
| it has come to life, consuming material and | | | | material flow are used. When the spark |
| air thus producing smoke and damage. A spark | | | | sensor detects a spark, or when the preset |
| detection and extinguishment system | | | | spark threshold is exceeded, the installed |
| eliminates one of the three elements (the | | | | device is activated from the control |
| ignition source) before it becomes a fire. | | | | console.CO2 ExtinguishmentIf parts of the |
| In this way there is no fire, no smoke, and | | | | plant, complete machines or sensitive filter |
| no damage.Spark detection and extinguishment | | | | systems are to be extinguished, a C02 system |
| systems are able to detect even the smallest | | | | can be activated by a spark detection system. |
| of sparks or hot particles in extraction | | | | For this application, spark sensors monitor |
| ducts, drop chutes or mechanical conveyors, | | | | the ducts leading to these areas. Upon |
| and to instantly trigger countermeasures. | | | | detection of sparks, an alarm message is |
| Countermeasures can be: activation of an | | | | transferred to the CO2 system through |
| extinguishing system, diverting the transport | | | | voltage-free relays of the control console. |
| path or interrupting the production. All | | | | The corresponding parts of the system are |
| these measures are taken within a split | | | | simultaneously shut-off by activating |
| second.Detection of the ignition source is | | | | shut-off gates so that the incoming CO2 can |
| made by means of spark sensors recognizing | | | | now flood the contained area.Central |
| the infrared radiation of sparks and glowing | | | | Visualization SoftwareEvents recorded by |
| particles. These sensitive spark sensors are | | | | several consoles that are installed in |
| even capable of detecting sparks through | | | | different areas of the plant are accessible |
| layers of dust or through the conveyed dense | | | | through the visualization software. Such an |
| material flow. The sensors give alarm | | | | application offers many advantages: Central |
| signals to the control console, which | | | | actuation and processing of all spark alarms |
| processes the signals and activates the | | | | on one monitor is possible. The central |
| appropriate countermeasures automatically. | | | | acquisition of all events provides the |
| Normally an extinguishing device is | | | | operator with meaningful and comparable data. |
| triggered, which is installed downstream from | | | | The remote control of the individual spark |
| the spark detectors. This device releases a | | | | extinguishing systems make it possible to |
| mist of water in the duct section where the | | | | react rapidly on each alarm event and allows |
| sparks are transported. When no additional | | | | time and cost savings and shorter production |
| sparks are detected, the extinguishment spray | | | | interruptions.Spark Detection and |
| is automatically stopped. While the | | | | Extinguishing Systems Insurance Premium |
| extinguishment takes place, the production | | | | RatesFire insurance companies have |
| process can continue unless otherwise | | | | acknowledged the minimized risk when |
| desired. Due to this special operation | | | | automatic spark detection and extinguishment |
| principle, spark detection and extinguishment | | | | systems are installed, and may grant |
| systems are classified differently than | | | | discounts on insurance premiums. |
| sprinkler systems, deluge systems, or even | | | | Precondition for achieving discounts on |
| explosion suppression systems.The Control | | | | premium rates is the use of an extinguishment |
| ConsoleThe centerpiece of a spark | | | | system that is approved by a commercial and |
| extinguishing system is the control | | | | industrial property insurance and risk |
| console.All signals given by the spark | | | | management organization. Factory Mutual is |
| sensors installed in different plant areas | | | | one such organization and the only North |
| are being accumulated and processed by a | | | | American organization to test spark detection |
| microprocessor. The extinguishing devices of | | | | and extinguishment systems. Factory Mutual |
| the affected areas are activated without any | | | | requires stringent manufacturing standards |
| delay.A practical fire protection concept | | | | and technical reliability that not only |
| also considers the demand for an almost | | | | applies to the system, but also to the |
| uninterrupted production. The use of | | | | planning, installation and after-sales |
| microprocessor technique including the | | | | service.ConclusionSpark detection and |
| corresponding software results in new | | | | extinguishing systems are among the most |
| possibilities to react on sparks. Integrated | | | | efficient fire prevention systems, which is a |
| counters and time recording systems allow an | | | | result of their highly developed technique |
| exact assessment of the spark stream. A | | | | and reliability. The use of these systems |
| graded use of the existing countermeasures is | | | | for various applications is even prescribed |
| then possible.For example, single sparks are | | | | by Factory Mutual. All these factors lead to |
| only extinguished, but for heavy flow of | | | | considerable investment reductions and |
| sparks or when single ignition sources are | | | | improved safety for your plant, people and |
| detected over a longer period, further | | | | production.Author |
| measures like machine shut down of the | | | | |
| affected plant sections have to be taken. | | | | Bob Barnum, Vice President of Sales for |
| Diversion of the material transport is also | | | | GreCon, Inc. Bob has over 30 years of |
| possible using fast-acting abort gates.The | | | | experience with pneumatic and mechanical |
| microelectronics has many other | | | | conveying. GreCon is an ISO 9001 and Factory |
| advantages.Ease of OperationWhere once little | | | | Mutual Approved manufacture of spark |
| lamps indicated a flow of sparks, the trouble | | | | detection and extinguishment systems. |
| message is now displayed in clear text. | | | | |