New central generation BM6 and faster automatic extinguishing system guarantee maximum safety.

Fires or a dust explosion are possible wherever small particles are transported mechanically and pneumatically. VdS-approved spark extinguishing systems from T&B serve as preventative fire protection.

Alongside the preparation of comprehensive protection concepts and the pure servicing of systems, T&B electronic as an installer approved by VdS also offers further services such as winter check (check on the system before the frost period) or existing installation check (check on the pipe network for corrosion). “We thus relieve our customers from their extensive operator tasks. The objective is to offer customers an all-round carefree package for fire protection by providing an optimum range of services. This requires extremely flexible work in the service department, which is where our strength as a comparably small company lies,” managing director Thomas Warnecke explains.

In pneumatic conveyor systems, spark detection and spark extinguishing devices should be installed downstream from the fan if possible. Thanks to the newly developed automatic extinguishing system, T&B is able to achieve minimum distances between spark detection and spark extinguishing. The time required to develop the atomised mist has been reduced down to 175 ms by the new T&B development. Thus the distances between spark detection and spark extinguishing is reduced by almost 50 % compared to competitors’ systems. In addition, a low flow pressure of 5 bar is sufficient for spark extinguishing systems from T&B. This allows the capacity of the pressure booster system to be reduced in any case. In many cases, it is also possible to use an existing service water network or the sprinkler system for water supply.

The extinguishing nozzles are fitted with a cap to prevent soiling. Extinguishing is maintained until the last detected spark has passed the extinguishing section, then the automatic extinguishing system closes automatically. The spark extinguishing system remains in stand-by so that any new sparks can be dealt with immediately. An adjustable spark threshold can be used for machine shut-down. The number of sparks detected is indicated at the spark alarm unit. The new generation of spark alarm units BM6 has an automatic detector test facility. The spark alarm units can save up to 2500 fire alarms or malfunctions and display these as plain text. Connection to a network provided by the customer is possible via an OPC interface. Remote maintenance via an internet interface is a further option.

The most important prerequisite for safe plant-related fire protection is the VdS-conform installation of spark extinguishing systems.

“The fact that there has not been a fire in an industrial plant for decades does not prove there is no fire hazard, it only shows that the operators have been lucky – and this luck may run out at any time.”

This is cited from a court ruling by the OVG Lüneburg dated 23 September 1976.

Amazingly, risk analyses which are done e.g. in the context of company evaluation according to Basel II by financial institutes consider many operational risks but do not take any account of preventative fire protection. This is all the less comprehensible since fires can result in high subsequent costs on account of operational downtime and may even threaten the economic existence of a production company. In addition, non-life insurers will usually grant large discounts if preventative fire protection systems are installed.

Preventative fire protection can have a payback time of just a few moments, but this is only the case if the protection concept that the installed system is based on corresponds to the technical standard and fulfils the demanding requirements of VdS Schadenverhütung (damage prevention). It is also imperative that a complete protection concept is prepared. According to Murphy’s Law (“Whatever can go wrong, will go wrong”), fragmented concepts that only protect parts of a production plant will always lead to a fire starting where there are no fire protection devices installed.

In relation to the investment volume of an entire pellet factory, the costs for the spark extinguishing system make up approx. 1%. For customers, fire protection is most cost-efficient if the installer of the spark extinguishing system is involved right from the planning phase, so that customer-specific protection concepts can be implemented.

Together with VdS Schadenverhütung and several leading insurance companies, T&B electronic has developed a basic protection concept for the pellet industry. Knowledge gained from known occurrences of damage as well as the latest technical standard were taken into account during development.

This concept is based on the VdS-approved spark extinguishing system from T&B electronic. The components of this spark extinguishing system reliably protect the risk areas in production against sparks, fire and explosion.

What exactly does “VdS-approved spark extinguishing system” mean?

Within the context of system recognition, VdS Schadenverhütung examines all the components of a spark extinguishing system in its own laboratories and guarantees through regular product audits at the spark extinguishing system’s manufacturer’s that the fire protection systems are always manufactured and tested in accordance with consistently high requirements. In other words, only VdS-approved systems guarantee that the latest technical standard is installed at a consistently high quality standard.

In addition, the installer of the spark extinguishing system must prove that he has planned and installed a specific number of spark extinguishing systems per year in accordance with the VdS directives without any problems. T&B electronic fulfils all the above-mentioned criteria and is thus an approved manufacturer and installer for recognised spark extinguishing systems.

In addition to the installation of a spark extinguishing system, it must be noted that further protective measures are designed to round off the concept. Thus, for example, pneumatic conveyor systems which are routed through fire walls or complex separation walls must be equipped with fire protection gates. These can be actuated both by the spark extinguishing system in the event of constant sparking or by conventional fire detectors if a fire breaks out in the building. A combination with T&B spark extinguishing control systems is possible.

The realisation of systematic machine shut-down is also important in the event of constant flying sparks. This measure is an explicit VdS requirement but is often “forgotten” on site. Shut-down is the only way to guarantee that fires do not spread to other parts of the plant.

The regular tests by VdS Schadenverhütung on the premises of the system’s operator in conjunction with the necessary inspections and maintenance by the approved installer guarantee that the spark extinguishing systems installed are always ready for use, even after months on “quiet” standby duty.

The plant sections monitored are always equipped with at least two detectors and one extinguisher. In addition to machine shut-down during constant flying sparks, each alarm is visualised at a manned control centre.

Spark detection is achieved using at least two spark detectors which monitor the entire pipeline cross-section. The spark extinguishing system is consists of a quick-opening solenoid valve and at least one extinguishing nozzle. The extinguishing nozzles are fitted with a cap to prevent soiling. The extinguishing process is continued until the last detected spark has passed the extinguishing section, then the automatic extinguishing system closes automatically. The spark extinguishing system remains in stand-by so that any new sparks can be dealt with immediately. The minimum extinguishing time is five seconds and is automatically extended if flying sparks persist; an adjustable spark threshold can be used to trigger machine shut-down. The number of sparks detected and the trigger threshold are indicated at the spark alarm unit. The spark detectors are equipped with built-in testing devices. The spark alarm units BM 6 have an automatic detector test facility. The spark alarm units can save up to 2500 fire alarms or malfunctions and display these as plain text. Connection to a network provided by the customer is possible via an OPC interface. In addition, the system permits remote maintenance via an internet interface. This way, the operating company receives fast online support in the event of a malfunction and cost-intensive service assignments may be able to be avoided completely.

In this context, the importance of system maintenance and inspections must be emphasised. The operating company only fulfils its legal obligations when the inspection and maintenance intervals specified in DIN VDE 0833 are kept. DIN VDE 0833 explicitly requires the regular inspection and maintenance of fire protection systems by the recognised installer. Forgoing inspections and maintenance can have a negative impact on insurance protection.

In addition to pure system inspections and maintenance, T&B electronic offers further services such as winter check (check before the frost period for sufficient insulation, trace heating etc.) or an existing installation check (check on the pipework for extinguishing water for signs of corrosion and deposits etc.). A check on the electric system parts in accordance with the Arbeitsstättenverordnung (German Workplace Ordinance) is also part of the scope of supply. This way, T&B electronic relieves the operating company of some of its extensive legal operator duties.