Automatic system UIS-48S for impulse fire extingui

 

 

 CONTENTS:

1. Purpose of the system.

1.1. Kind of activity for automation of which the system is destined.

1.2. List of automation objects where the system is used.

1.3. List of functions realized by the system.

2.1. The system’s structure and purpose of its parts.

2.2. Information on UIS-48S as a whole and on its parts necessary to secure the system’s operation.

2.3. Description of the system’s functioning.

2.4. The main advantages of UIS-48S.

Impulse technologies for supplying fire extinguishing substances are one of the new directions in the field of fire extinguishing. The main distinctions of impulse technology are: supply of fire extinguishing substances at a high (up to 100 m/sec) speed; creation in a very short period of time of a zone with high concentration of a fire extinguishing substance. High effectiveness of impulse fire extinguishing technologies is achieved owing to a powerful dynamic influence on the fire center, quick cooling of the fire center to the temperatures securing stopping of burning, inhibiting of the burning process when applying powder fire extinguishing compositions. The use of powder fire extinguishing compositions in installations of impulse fire extinguishing allows to apply them in various conditions: at the temperature of environment from +50 to -60⁰С; for extinguishing of fires of А, В, С, and E classes, when using powders of special purpose extinguishing of class D fire is possible; for extinguishing fires of technological equipment on open sites and in three-dimensional premises with not high impermeability.

The automatic system for impulse fire extinguishing is destined for active fire protection of objects on open sites, as well as in premises with high level of non-impermeability.

 

1.2 List of automation objects where the system is used.

The protected objects are as follows:

- transmission sea platform;

- stationary pump station

- pipe collector

- oil-refining factory

- any other object with increased fire danger

 

The fire extinguishing system secures:

·        Control of thermal background of the object’s protected zone;

·        Detection of burning on its early stage; of emergency situations, such as dangerous overheating of technological equipment, short circuit in electric installations etc;

·        Control of weather conditions (wind speed etc.) when calculating the coordinate of the fire center;

·        Exactness and reliability of determining the place of origin of the emergency situation;

·        Automatic testing of sensors;

·        Immediate notification of the fuel supply control dispatcher of any event (contingency) in the system’s devices;

·        Showing of a plan of the protected object in case of emergency situation or burning indicating the specific sensor and place where the situation happened;

·        Showing on the monitor of the operator’s automated work place of brief instructions for the personnel on duty;

·        Creating of a non-editable report of events happening during a shift;

·        Automatic aiming and launching of executive devices for supplying fire extinguishing substance to the set point when exceeding the established thermal stream level value;

             The system envisages the presence of:

·        Transfer by the system’s operator from the automatic regime to the remote one with the description of the reason for transfer;

·        Multilevel access to the system with the aim of differentiation of functional possibilities of the serving personnel;

·        Control of good working order of the object’s microcontrollers, notifies, sensors and other apparatus included in the structure of the object’s active fire prevention system, as well as of signaling and communication lines;

·        Control of technological trains;

·        Possibility of joint work with a video observation system;

·        Control of access to controllers’ boxes;

·        Uninterrupted work of the system during the set period of time in the absence of main power supply.

 

The system represents a distributed independent system consisting of software and hardware and is destined for detecting fire, for collecting and processing of information from detecting devices, for taking decisions on extinguishing fires and for controlling executive devices (e.g. automatic fire extinguishing installations).

The system consists of:

·     Technical means for early detection of burning, self-ignition centers, smoldering – thermal stream sensors in infrared spectrum;

·     Fire informers;

·     Technological signaling means;

·     Notifying means;

·     Executive devices controlling means;

·     Energy independent power sources;

·     Data processing, transmitting and reproducing means;

·     Special software;

·     Means for connecting the operator’s station with controllers.

 

The system consists of N modules responsible for N background of the object’s protection zones.

 

 

The system for the object’s fire protection can be represented by an aggregate of two mutually connected subsystems: by a subsystem for fire information detection and processing (UIS-48S); and by a fire extinguishing subsystem.

The subsystem for fire information detection and processing consists of detecting devices, information transmitting devices and an operator’s automated working place (AWP).  

The detecting device represents a set of thermal stream sensors (hereinafter - sensor) for early detection of an ignition center and performs detection of a fire on an early stage of its development. The use of sensors for early detection in the fire protection system (FP) of objects allows to increase the efficiency of organizing fire protection, what essentially decreases the damage from fire.

The sensor is an optical and electronic analog and digital device securing measuring of the electromagnetic infrared radiation stream and transfer of this information in digitized form through a RS-485 interface. The sensor’s sensitiveness is adjusted in a programmed manner.

The sensor is a technological one. A signal of change of thermal background level in conditional units (c.u.) is transmitted in a digital form to a microcontroller. The sensor’s body is protected from dust and moisture. The sensor’s arrangement allows to test its sensitivity and the fact of the inspection window’s becoming dusty periodically.

The sensor’s angle of vision is 90 degrees, the working regime is uninterrupted, the address for each sensor and speed for data transmission are set in a programmed manner.

The sensor takes into account:  the change of environment’s temperature by means of displacement of the temperature gradient, the presence of natural and artificial lighting sources (provided the rules for the sensor’s installation relatively to the lighting sources are observed).

The sensor’s construction corresponds to general safety requirements.

 

ASIFE secures forming of 4 levels of signals. Possible adjustments of a microcontroller’s software are given in Table 1.

 

                                                                                                       Table 1

Levels of sensors’ adjustments

 

         In the process of operation and technical servicing (according to the schedule of conducting the established works) correction of each sensor’s adjustments is performed. A sensors adjustment correction report should be approved by technical managers of the enterprise and by the servicing organization.

         Based on experimental and industrial exploitation of many years it has been determined that the main devices for processing information are industrial microcontrollers of the ADAM 5510 series (hereinafter – microcontroller) produced by Advantech.

A microcontroller is a functionally finished autonomous communication microcontroller destined for implementing the distributed systems for data collection and control. The microcontroller contains a built-in ROM-DOS, MS-DOS compatible operational system, excluding the support of the BIOS system standard service. Application of this microcontroller provides the user with a possibility of creating software on top level languages with the use of IBM PC compatible computers.

         In fact, microcontrollers represent programmed computers, which can be programmed for control of any devices according to any algorithm.

         One microcontroller is installed for several zones of fire extinguishing, performing collection of information from thermal stream sensors, manual launching buttons, control of executive devices of fire extinguishing installations, as well as securing control of the system for light and sound notifying and of electromagnetic valves of control units.

         All microcontrollers installed in the fire extinguishing zones are connected between each other by wire of a “twisted pair” type or through optical and fiber cable, and data exchange is performed through a RS-485 interface.

         A microcontroller passes all information to the operator’s automated working place located with the personnel on duty. In case of failure of the operator’s automated working place a microcontroller continues its work in autonomous regime.

The fire extinguishing subsystem includes a set of impulse installations of powder fire extinguishing located around the protected object. The installation includes the basic plate with a cassette mounted on it having sprayers and a support and turning device securing change of the cassette’s position in horizontal and vertical planes. The control is performed from the operator’s AWP through the controlling control and address module both in automated and manual regimes.

The software part of the operator’s AWP is developed with the use of a Borland Delphi vision design means and a component of work with the data base under control of MySQL server.

The executive devices are impulse sprayers blocked in cassettes.

  The software performs:

·  Receipt, processing of signals from sensors, control of manual launching means and devices for measuring other parameters;

·  control of devices for data transmission, notifying and execution;

·  showing on the operator’s monitor in case of emergency situation or burning of a plan of the protected premises indicating the specific sensor and place where the situation arose;

·  visualization of the system’s current condition;

·  storing and reporting all events happening in the system (report files are encoded and concealed from users);

·  in case of pre-emergency and emergency situations a window with instructions for the operator appears.

·  Administering and differentiation of access levels by means of a password system.

 

All protected objects are divided into fire extinguishing zones and are represented schematically on the operator’s AWP monitor.

Thermal stream sensors are located in each fire extinguishing zone so as to enable organizing of a coordinate net of the protected zone for subsequent determination of a fire center coordinate. The place of location and each sensor’s thermal stream level are shown on a detailed plan of each zone of the operator’s AWP. The programmed microcontroller performs control of integrity of communication lines from the thermal stream sensor, of executive devices launching circuits, of sound and light notification systems, and of the main power voltage.

Information on thermal disturbances is fixed by thermal stream sensors and transmitted to the programmed microcontroller, which, depending on the signal’s level, determines the fire center’s coordinate and forms a command impulse for aiming and launching of the corresponding executive devices.

“NORM”

The sensors’ thermal background level does not exceed alarm signals. Light and sound informers are turned off. All sensors, communication and control lines are in working order. Signals of this are transmitted to the operator’s AWP.

“ATTENTION”

In case of detecting by the sensor of an increase of the thermal background level above the “ATTENTION” set level, the data received from the sensor is analyzed on the microcontroller and the zone is transferred to the state of “ATTENTION”. No turning on of the extinguishing system happens. Signals of this arrive to the operator’s AWP.

“DANGER”

In case of detecting by the sensor of an increase of the thermal background level above the “DANGER” set level, the data received from the sensor is analyzed on the microcontroller and the zone is transferred to the state of “DANGER”. At the same time, sound and light notification “FIRE” is turned on in a pulsing regime with a frequency of 1 Hz. No turning on of the extinguishing system happens. Signals of this arrive to the operator’s AWP.

“FIRE”

In case of detecting by the sensor of an ignition center (the level “FIRE” was exceeded), the data received from the sensor is analyzed on the microcontroller. This and the following zones are transferred into the state of “FIRE”. At the same time, sound and light notification “FIRE” is turned on, the fire center’s coordinate is determined, the impulse installation is aimed according to the set coordinates. Signals of this arrive to the operator’s AWP.

“FAILURE”

In case of failure in a zone microcontroller transfers this zone into the state of “FAILURE”. At the same time, sound and light notification “AUTOMATICS” is turned on in a pulsing regime with a frequency of 1 Hz, and a possibility for automatic launching of extinguishing is turned off for this zone. The zone is transferred into the regime of “AUTOMATICS OFF”. Signals of this arrive to the operator’s AWP. After eliminating of the failure the zone is transferred into the state of “NORM” and “AUTOMATICS ON”.

In case of exceeding the levels of “Attention”, “Danger” or “Fire” the zone is transferred to the corresponding regime, since these regimes have priority over the “Failure” regime.

The LIST of possible failures when the microcontroller transfers the zone into the “Failure” regime is as follows:

1.                            Short circuit or rupture of executive devices lines.

2.                            Absence or failure of an impulse fire extinguishing installation.

3.                            A microcontroller’s failure.

 

“LAUNCHING OF EXTINGUISHING BY THE OPERATOR”

Remote launching from the operator’s AWP of the fire extinguishing system is possible separately in each zone irrespective of the automatics regime. In this case, a sound and light notification “FIRE” is turned on. The system of extinguishing is turned on (a valve opens for the set program interval). Signals of this arrive to the operator’s AWP.

 

“LAUNCHING OF EXTINGUISHING IN REMOTE REGIME”

Manual launching of the fire extinguishing system in each zone is performed from the operator’s AWP. In this case, a sound and light notification “FIRE” is turned on. The impulse fire extinguishing installation is aimed to the set sector and launching of the fire extinguishing system executive devices is effected. Signals of this arrive to the operator’s AWP.

 

2.4. The main advantages of UIS-48S.

The main advantages of the developed FP system as compared to the traditional ones are as follows:

- a possibility of detecting fire on an early stage of its development both on the equipment itself and in case of fire on the adjacent territory;

- essential shortening of time for taking by the servicing personnel of a decision on organizing extinguishing of fire both in automated and manual regimes;

- effective control of automatic fire extinguishing means, issue of recommendations on organizing a fire extinguishing process;

- long term of operation of fire extinguishing systems executive elements, in a number of cases 25 years and over;

- possibility for operation and work in the temperatures of the surrounding air from +50 to -50⁰С and lower;

- simplicity of servicing, repair applicability, high reliability;

- substantial economy of financial means on implementation and servicing as compared to traditional systems for fire detection and extinguishing;

- recording of work of the object’s FP system with a possibility of immediate transmission of objective information.