BRANCH SOLUTION

Minifog PressProtectFire protection solutions for industrial presses

During the production of OSB, PB, MDF andHDF boards with continuous or multi-openingpresses, combustible materials for examplewood chips, fibers, paraffins and adhesivesincluding flammable liquids such as hydraulicand thermal transfer oils are used.

Should these inflammable materials ignite, e.g.by overheating or friction, serious fires canvery easily develop, which in severe cases maylead to extensive property damage followed by long undesirable and expensive downtime.Fires also put human life at risk.

Continuous Presses

Fire hazards generally exist on the whole pro-duction line. Metallic friction, condensation ofvolatile substances, oil leaks and fiber depositsparticularly in close proximity to the pneumaticexhaust systems, may all assist in starting a fire.

From experience the highest risk of fire comesfrom the press inlet and the press outlet, whereamongst others units, such as cleaning, lubri-cation and extraction systems exist. In the pressinlet the entering pre-compressed material matand the deposits are exposed to strong physicalinfluences, by extreme heat supply and highpressure, and thus may easy ignite. A particu-larly high number of fires start at the pressoutlet, where volatile substances leave theextremely hot board and ignite upon contactwith oxygen in the air.

Multi-Opening Presses

In a multiple-opening press the material is heated intensely during the extended period oftime spent within the press cycle. As the pressis opened, the compressed boards are exposedto oxygen. Should a glowing ember be producedduring the pressing sequence, this rapid supplyof oxygen may lead to a fire. Deposits on theframe construction will further assist the fireto spread rapidly in the vertical direction(chimney effect). For this reason, it is recom-mended to include both the press loader andunloader into the extinguishing concept.

Flexible hoses supplying the press with thou-sand litres of hydraulic and thermal transfer oilcreate an additional fire risk. As they are sub-ject to mechanical stress during the openingand closing cycle of the press, cracks that maydevelop causing leakage of pressurized oil canresult in a severe fire. As the thermal oil ages,its ignition point sinks, thus considerably in -creasing the risk of self ignition on hot surfacesas a result of leakage.

A distinct fire risk can also be identified in thepit below the press – e.g. from hydraulic orthermal transfer oil equipment and accumulatedfibers and grease. This particular risk shouldbe protected as a separate extinguishing zonewith the addition of a special foaming agent.

RISKSdetect

The complex design of the press prevents thewater spray from the ceiling sprinklers fromreaching and wetting the fire in it’s interior.Protection with a Minifog PressProtect systemwill help to protect your production systemsfrom fire damage and expensive downtimes.

Minifog PressProtect – optimised for you!

The Minifog nozzles only require a supplypressure of 4 bar. As the extinguishingsystem operates under low pressure, connection to a sprinkler system is usuallypossible, eliminating the requirement for anadditional water supply, with a considerablesaving on both space and costs and makesalso retro-fitting easy.

The relatively large orifice of the nozzlesand the integrated fine sieve prevent blockages and even enable the use of gal-vanized piping. This means that expensivestainless steel pipes or specially treatedextinguishing water can be avoided. A capwith retaining chain protects the nozzlefrom outside contamination.

As well as being activated by hand at thedeluge valve stations, the Minifog systemcan be activated by manual release unitslocated in close proximity to the press andin the control room.

The approved Minimax deluge valve stationscan be opened and closed by remote con-trol: This enables the use of water to bereduced to an absolute minimum. Once activated, they remain in an open position,even if the electricity supply fails or is damaged as a result of fire.

The manifold for the deluge valve stationsincluding the corresponding release solenoidvalves should be positioned in a close butsafe distance away from the press to alwaysensure the safe release of extin guishingwater, even in the case of a sudden possibleexplosion.

Rapid fire detection is also of upmost im -portance in areas with high temperatures:fast infrared flame detectors are used inthe inlet, the outlet and both the upper and

EFFECTIVEminimum effort, maximum benefit

CONCEPTeffective and fast

lower heat tunnels of continuous presses.Flexible and temperature resistant fiber op -tic cables are used for thermally separatingthe electronic components of the flamedetector from these hot areas. The costintensive provision of permanently necessarycooling air can be avoided.

The open areas of the press are monitoredusing nuisance alarm-proof infra-red detec-tors, which are equipped with a monitoringsystem to both function and against con -tamination of the optical window.

The fire detection control panel monitorsall flame detectors, including their functionand visual monitoring systems, pressureswitch, blocking equipment and extinguish -ing valves. The time of every alarm, in addi-tion to the start and finish of extinguishingprocesses, is logged to the milli second in a storage memory for more than 50,000 en tries. All lines are monitored separatelyfor wire breaks and short circuits. The FMZ 5000 meets the requirements of bothEN 54 Part 2 and 4 for fire detection con-trol panels and EN 12094 Part 1 for thecontrol of gas extinguishing systems. It hasbeen approved by VdS and FM for simulta-neous use as a flame detector, fire detectorand control panel for all types of extinguish-ing systems. As a result of this, all fire pro-tection tasks can be carried out with justone control panel.

All automatic detectors are equipped withan electronic self-monitoring of optical in -tegrity, sending a signal to the control panelin event of contamination: If residues col-lect on the optical window of the detector,a fault message is displayed on both thedetector in question and the fire detectioncontrol panel, before the detector “loses itssight“.

The Minifog PressProtect system is alsoavailable for use in Ex Zone 22, in accord -ance with ATEX 94/9.

For optimal operating comfort, in additionto alarm transmission and alarm storage,the fire detection control panel can be con-nected to the WinGuard visualisation andalarm management system, which offersthe possibility of operating the control panel,display messages optically or graphically ona monitor and forward selected alarms viashort text message, email or fax by using aspecial message module.

Pre-configured and fully coordinated inter-faces for the machine reactions were de -fined in close collaboration with renownedpress manufacturers. Signals can be trans-mitted to the press PLC via potential-freecontacts or a bus system.

BRANCH SOLUTIONMINIFOGPressProtect – convinces

Minifog PressProtect systems create fine droplets thus increasing the contact area forheat transfer thereby optimizing the coolingeffect of the water. In addition – due to rapidvaporization of the small water droplets withinthe location of the flame – a large amount ofsteam is produced, which prevents the oxygenfrom reaching the fire. An effective combina-tion for rapid control and extinguishment of a fire.

Impulse nozzles with their unique spray patternare an integral part of the Minifog protectionconcept. They are positioned in two levels onboth sides of the press, as well as in the inletand outlet, to securely protect the risk areasand minimise water use.

The low volume of water, the special spraypattern and the targeted nozzle arrangementminimize the danger of distortion of hot ma -chine parts – proven under to-scale fire testsand metallurgical investigations. Damage isavoided and the press remains in an operablecondition.

Such efficient fire fighting has also convincedvarious approval entities. Minifog PressProtecthas achieved the first VdS approval for pressprotection with fine spray technology. In addi-tion to this, the large international insurer andapproval institution, FM Global, has witnessedsuccessful testing of the Minifog concept con-firming its reliability and performance.

Please see Minimax product sheets for detailed information.

OPTIMALMinifog PressProtect – the solution

Minimax customers trust our solutions:Minifog fine water spray systems have proventheir functionality and reliability countless timesunder the severe operating conditions in thewood processing industry and are successfullyoperated worldwide on almost 200 presses.

Systems for the protection of other high-riskareas, such as pneumatic conveying systems,thermal oil or hydraulic oil rooms and channels,press fume extraction ducts and switch rooms,complete the protection concept.

Minifog PressProtect forthe protection of presses

F

F

F

FF

F

F

F

FF

F F

F

F

HAT

FMZ

F

F

FF F F

HAT 3000

HAT 3000 HAT 3000

HAT 4100

HAT 3000

FM

PLC

WinGuard

Z

Control room

Deluge valve set

Strainer with fine sieve

Impulse nozzle

Gate valve

Extinguishing zone

Connection to sprinkler systemor independent water supply

Manual release operating panel

Fire detection and extinguishing control panel

Alarm horn

Strobe light

Manual push button

Infrared flame detector with fibre optic

EZ

EZ 1

EZ 1

EZ 4

EZ 2 EZ 3

EZ 5

EZ 2 EZ 5 EZ 4 EZ 3

Infrared flame detector

Transport direction

AL0

5e_

03

/05

.03

/2/0

5.0

9/H

A

P

rin

ted

in

Ger

man

y

4365 Federal DriveGreensboro, NC 27410Phone (336) 299-2933Fax (336) 299-2944www.flamexinc.com