Calculation and installation of fire-prevention, industrial, domestic water supply systems

Internal water supply systems receive water from the city-wide water supply network and supply it directly to every apartment, workshop, office. The quality of water supply to consumers depends on the competent design and installation of internal water supply systems.

Types of internal water supply

In accordance with the method of using water, internal water supply systems are:

• fire-fighting;
• household;
• watering;
• production.

Household systems supply water for washing, washing, cooking. Therefore, the water must meet the requirements of state standards.

Fire protection internal system water supply is used for fire extinguishing, stopping the spread of fire inside the building.

Production internal system water supply provides water to factory and factory workshops.

Watering internal water supply serves for watering flower beds, washing sidewalks near the house, cleaning corridors and halls.

To reduce the cost of equipping internal water supply systems, various types are combined: watering with household, watering with production.

The internal water supply system is selected taking into account the purpose and architecture of the building. So, at high-rise facilities, one water supply system is equipped that performs all functions.

Components of internal water supply systems

The internal water supply network is equipped with the following components:

• input;
• metering device;
• pump (not always required);
• shut-off valves;
• water pipes;
• water taps.

Input - this is a pipe located between external water distribution networks and a metering device.

Knot accounting can be located in a serviced building or in a specially equipped room.

Pump needed when the pressure in the external water supply is not enough to deliver water to the upper floors.

Plumbing network distributes the resource to end users. Water-folding fittings internal network - these are taps and mixers through which the consumer receives the resource.

Pipeline accessories the internal water supply system controls the movement of the resource.

Internal water supply schemes

The internal water supply network diagram is divided into the following categories:

• Simple. Consists of input, water meter and water supply. It is used when the pressure in external networks is higher than necessary to provide the upper, most distant consumer of this structure;
• With a regulating capacity. It is used if the pressure in the pipes is insufficient daily for a short period of time;
• With a pump. It is used when the head in the external network is constantly low.

Calculation of the internal plumbing system

The calculation of the internal water supply should be carried out according to the following algorithm:

1. Creation of an axonometric diagram.
2. Determination of the direction of the liquid from the point of connection to the external water supply to the dictating device.
3. Dividing the network into sections for calculation.
4. Determination of resource costs for each site.
5. Determination of the total pressure loss taking into account the local resistances of the sections.
6. Choosing a water meter and calculating the pressure loss in it.
7. Calculation of inlet pressure loss.
8. Calculation of the height of the rise of the water column.
9. Calculation of the pressure at the point of insertion into the external water supply system and reconciling it with the indicator of the guaranteed pressure.
10. Calculation of the pump for internal water supply.
11. The choice of the dictating plumbing fixture - the most distant in height and length from the input.

The calculation of the level of the laying of the water supply inlet depends on the depth of soil freezing:

h=Hpr + 0,5

here Hpr - the level of soil freezing, in meters.

The calculation of the pressure drop in the water meter is calculated as follows:

hv = s * Q2

here s - tabular value of the resistance of the meter,Q2- water consumption per second squared.

Calculation of the pressure of the internal water supply provided by the pump:

Hp=Hgeo + Hr + Hs + Hg

here: Hgeo - the height from the pump to the dictating plumbing equipment, Hr - pressure losses in the considered section of the water supply system, Hs - free head of plumbing equipment, tabular value, Hg - the minimum guaranteed pressure in the external line.

Installation of internal water supply

Regulated procedure for the installation of internal water supply systems:

1. Before plastering, marking and installation of fasteners for highways is carried out.
2. Installation of resource metering devices.
3. Installation of highways with outlets for plumbing equipment.
4. Checking pipelines for strength and tightness (pneumatic or hydraulic).
5. Installation of water fittings in the internal water supply system.
6. Installation of fire hydrants.
7. Cleaning and disinfection of pipes (if necessary).
8. Checking the work and launching the internal water supply network.

Pipe installation

Internal fire-fighting water supply is equipped from non-galvanized metal, industrial - from plastic, steel, ceramic pipes.

If the building is equipped with several inputs, they are connected to different points of the external water supply. If a common pump is used, the inputs are combined. It is necessary to install check valves at the inputs when water tanks are used or the chain of inputs is united by a single pipeline inside the building.

There should be a distance of 1.5 - 3 meters from the inlet of the domestic water supply to the outlet of the sewage system, depending on the diameter of the water pipe. Internal water supply connections for various purposes can be equipped together.

At the point of connection of the input of the internal water supply network to the external water supply, a well is installed, where the stop valves are located. The turns of the highway are reinforced with stops.

Installation of fire protection networks

Vertical highways of internal fire-fighting water supply in houses with a height of more than 17 floors are made double, from below and from above connected by jumpers. Internal water supply networks are equipped with 2 exits to the street, fire hoses are connected to them.

Taps, plugs and other fittings of the internal water supply system are installed in dry, heated places.

During the installation of internal water supply systems, fire hydrants are placed in public places: stairwells, lobbies at a height of 1.35 m. Double hydrants are placed one above the other, not lower than one meter from the floor.

Video on how to check the fire water supply system: