When is it necessary to install an internal fire water supply and how to install it correctly? What do you need to know to get it right? The article will answer these questions.
When ERW is required in a building
The list of requirements for the joint venture internal fire water supply is indicated in a number of regulatory documents of the EaP 10.13.130 2009.
Mandatory installation of pipeline:
- In residential and public buildings.
- In administrative and domestic buildings.
- Industrial plants.
- In production warehouses.
When determining the flow rate, knowledge of the number of storeys and volume of the structure is required. In residential premises, the length of the corridor is taken into account.
In industrial buildings and warehouses, the level of fire resistance of the building, the degree of fire safety and the volume of a particular room are taken into account.
In industrial buildings and warehouses, if the height is more than 50 m, and the indicators are indicated with a volume of up to 50 thousand m33 , it is recommended to use four-jet pumps with a head of 5l/s If the volume of the room is higher, the use of eight-jet models is recommended.
To determine the amount of water used for fire fighting, it is necessary to take into account the height of the compact jet and the diameter of the spray. With the free pressure of the fire cock, it is necessary to achieve a compact jet, the height of which will allow the fire to be extinguished at the highest point of the building.
Characteristics of the fire water pipeline B2
Fire-fighting water supply B2 is necessary in order to extinguish fires with water. In accordance with the requirements of regulatory documentation, such a system must be installed:
- In residential buildings with 12 floors and above.
- In buildings of administrative structures with a number of storeys of 6 or more levels.
- In club and theater premises where there is a stage, cinemas, on the territory of the assembly and conference halls, which are equipped with appropriate samples of cinema equipment.
- In dormitory buildings, at public facilities, the volume of which is more than 5 thousand m33;
- In administrative and amenity buildings at industrial enterprises, with volumes from 5 thousand m33.
Features of the scope of application of the SV B2, equipped with a set of fire hydrants
According to regulatory documents, the method of installing the B2 system is subordinate to the B1 and B3 systems. It follows from this that if there are B1 or B3 networks at the facility, it is necessary to connect the B2 fire water supply to the B1 or B3 network riser.
Indicators of the diameter of the B2 risers must be at least 50 mm. The zone of their placement is the territory of the staircase and the corridor. The location of fire hydrants with a diameter of 50 mm requires a level of 1.35 m above the floor surface.
They are placed in lockers. The presence of a rolled hemp fire hose, the length of which is from 10 to 20 m, is important here. One end of the hose is equipped with a half nut to quickly attach it to the fire hydrant device. The other end is fitted with a conical fire nozzle to produce a compact water jet that is 10 to 20 meters long.
How to determine the amount of water needed for ERW
It is important to take into account the nature of the individual features of the object. If this is an industrial warehouse building, where all fire-fighting water supply devices with a diameter of 100 and a unit weight of kg are installed, it is recommended to increase the minimum flow rates in accordance with the requirements of regulatory documentation. For this, steel frame structures can be used.
Pipeline freeze protection
If a well or a plastic pipe of an external fire-fighting water supply system freezes in winter, you can connect an electric cable to the pipes in severe frosts. When installing the system, it is allowed to use additional insulation with special materials. Need to provide frost protection for fire-fighting plumbing.
outdoorpipes and plumbing can be insulated with foil tape and a voltage cable, which consists of three cores. The foil serves as a heat sink and prevents overheating. Wrap the pipe with insulation. So that there are no loads in the trench where the pipeline is located, it is concreted.
All fittings are clean, it is recommended to additionally coat them with an anti-corrosion compound or paint. Before gluing the tape, the pipe must be cleaned of dust and dirt.
There is a faster, but not as convenient way. Cut strips of foil isol or isospan, glue them with tape.
You can wind several layers of mesh on the pipe, coat with glue and wrap it with insulation. This is the most reliable way to protect the fire pipeline from freezing, designed for long-term operation.
Where fire hydrants are used
This system has been known for fighting fires for over 200 years. The fire brigade always has the nearest hydrant at its disposal. Its presence is mandatory in every region. Their accessibility, ease of use and visibility on the territory are important.
Hydrants that are located in a residential area must supply a jet of water at 5700 l / min. It is necessary to locate the SG along the length of the road, 2.5 m from its edge and up to 5 m from the wall of the nearby premises.
It is forbidden to install it on the territory that is intended for the movement of cars and on branches from pipeline lines. Install a fire hydrant so that you can put out a fire at any time.on the object that is assigned to this network. It is important that at least two hydrant hoses are available with water flow rates for outdoor fire extinguishing from 15 l / s.
About the internal plumbing
Standards SN and P regarding the internal water supply and sewerage system of the facility are provided in order to design systems that are just under construction and to reconstruct existing ones:
- domestic water supply;
- sewer;
- drains.
Mounting Features
Fixation of pipelines can be carried out by supporting the wall and partition in the area of the mounting hole. It can be supported on the basement floor through the places of concrete or brick columns, brackets along the entire length of the wall and partition. The pipeline is also supported on suspensions to the surface of the floors.
During the installation of a fire water pipeline, if the pressure of the fire hydrant is over 40 m, a diaphragm is provided between it and parts of the connecting head. This will be required to reduce excess pressure. You can install diaphragms that have the same hole diameter on buildings with three or four floors.
There must be a distance between the floor and the highest point of the floors not less than what is indicated in the table:
| Building height | Type of building | Fire jet length |
| Up to 50 mm | Residential,public, industrial and auxiliary buildings of industrial enterprises | 6 m |
| More than 50 mm | Residential buildings | 8 m |
| More than 50 mm | Public, industrial and auxiliary buildings of industrial enterprises | 16 m |
How to make a calculation for ERW in the HydroVPT program
If there is an ordinary internal fire water supply, which consists of taps and pipes, you can calculate how to mount it using the Internet program. Calculation results - flow and pressure indicators.
Consider the scheme of SP 10 13130 internal fire water supply. To calculate the required parameters, we will enter the number of cranes that are needed according to the standards.
Switch to the program and indicate that there are, for example, 2 jets of 2.5 liters each. The height of the room is 3 m, the crane marks are 1.35 m, there is no control unit. Let's draw a ring with a diameter of 50 mm and a dead end. Pipeline diameter - 65-80 mm.
Enter all the data, do not change anything in the "Regular section" section, since these indicators suit us. Let's enter the number 0.000005 and simulate a formal sprint sprinkler - the red dot at the top of the screen. It will not be taken into account in the program, but this item is required.
Introduce the geometric height of the dictating sprinkler 3 m, the height of the control unit and the coefficient - 0.2 taps of 2.5 liters each. Let us choose the minimum values of the diameter for determining the branch pressure - 0.001. The calculations take into account local pressure losses. We opensection "Fire hydrant. Pipeline". We select and substitute automatically the value of the fire hydrant. 2.6 l/s, 0.1 MPa, 50 mm tap are standard values that can be used in our calculations. We confirm the entered indicators and proceed to the choice of the diameter of fire hydrants. We enter an indicator of 50 mm. For supply pipelines - 67 mm.
Finish by defining the length of the segments. The first is the distance to the fire hydrant. We introduce indicators of 2 m at a height of 1.65, since this fire water pipeline has a downward direction. The length of the ring pipeline is 3 m. Enter the same indicators for the second tap.
The whole system is entered, click "Finish", and the program will automatically calculate the necessary indicators.
Summarize
Fire-fighting water supply is a mandatory device to ensure the fire safety of buildings and other areas. The installation of such a system implies compliance with the requirements specified in the regulatory documentation for the ERW system.
