The purpose of this article is to show typical errors during installation and when receiving erroneous recommendations from sellers of plumbing products. The information below will be useful for people striving on their own to develop a sewer project with its subsequent installation.
Also, this material will not be superfluous for homeowners who are not familiar with the installation technology of the sewer system (CS), when accepting work performed from plumbers and other third-party organizations.
What bias sewer pipes should be, what are the requirements for the maximum occupancy of the drainage system and for the installation of open and closed systems - will be discussed in this article.
Read also: What should be the wiring in a private house, do-it-yourself installation, instructions for beginners
Internal sewerage and requirements for it
External K
Internal sewerage (VK) - this is an engineering system of pipelines and means for collecting water, fecal matter and other household waste from specific consumers and for taking them out of households, industrial complexes and other structures.
VC is divided into the following types:
- Storm drains (K) or drains. Produces drainage of melt and rain water
- United K. - produces the drainage of domestic, industrial, as well as storm and melt water
- Household K. - all household plumbing and sanitary appliances are connected to it (dishwashers and washing machines, sinks, toilet bowls, etc.)
- Industrial K. - designed to drain unsuitable for technical use of water
Elements of V.K. systems
- Water receivers - toilet, bathtub, sink, washing machine, etc.
- Siphons or hydraulic closures - are barriers to the passage of sewer gases into residential and industrial premises. Almost all receivers are equipped with this element.
- Dirty water outlets - horizontal pipelines with a slight slope, to which all water receivers are connected.
- Risers - vertical pipeline
- Collectors - pipelines with a large horizontal slope compared to bends. Designed to collect all the water from the risers and bring them to an external sewer
- Fan pipes - ventilation connected to the CS is necessary to stabilize the internal pressure of the latter and remove malodorous gases
Internal circuit K
We will not consider in detail the work of the entire CS and its individual elements, we only note that from the water receiver, the effluents through the hydraulic locks through the outlets enter the horizontal outlets, then the dirty water through the risers, collects in the collectors and is discharged into the external sewer (septic tanks, wells).
The fan system regulates the pressure in the CS and is a branch for harmful gases. Cleanings and revisions are sealed technical hatches on bolted or threaded connections through which revision work is carried out.
House connection diagram
The main element of the internal CS is non-pressure pipes: cast iron, asbestos-cement and plastic. The advent of plasticelements is a "breakthrough" in plumbing - high tightness and durability are widely used in solving many architectural and design solutions.
Efficiency of K. system
Internal sewerage
Despite the simplicity of the VC device, it is subject to few, but strict requirements, non-compliance with which entails a number of unpleasant consequences, the main of which relate to taps:
- constant slope towards the drain along the entire length of the pipeline
- tightness of joints and resistance to internal pressure up to 0.5 atmospheres
- the diameter of the waste pipes must not decrease
- style and sockets should be installed towards the movement of water
- when wiring the system, it is not recommended to use sharp and right angles
- connection to the compressor station must be through hydraulic seals
- the diameter of the fan pipe must be equal to the diameter of the riser, and its end must be brought out to the roof
Permanent slope of sewer pipes
How to
If it is relatively clear in terms of tightness, the diameter of the materials used and their wiring, then many justified questions arise about the slope of the K. bends. Let's consider them in more detail.
- The principle of sewerage sewage flow. It is applied everywhere, regardless of the purpose of the buildings, their number of storeys and their relation to the right of ownership. And for this you need a slope of the pipeline - it's hard to argue with that.
- CT tilt angle - this is the difference in the height of the sewer outlet from the water receiver in relation to further internal outlets throughout the K. system. This is true up to the entry of wastewater into risers, collectors and highways.
- Angles are measured in degrees however, due to small values, the latter is determined by the ratio of the difference in the location of the ends of the pipe segment along the horizontal level to its length (cm / linear meter).
Permanent slope of sewer pipes
As practice has shown, for the efficient operation of the COP, it is necessary to form a strictly defined angle. This is due to the need that for the withdrawal of various kinds of waste, the speed of the mud flow is needed, at which fecal masses, fatty substances would be best removed into the external sewer network. The wastewater velocity in the system should be about 0.7-1.0 m / s - only at this value will the fecal matter be discharged into the riser along with water.
At first glance, it seems that the more the angle of inclination is formed, the better. However, this is not the case, since the speed of passage through the branches and other effluents of different wastes varies. Water will drain quickly, and more viscous substances will not have time, and eventually stick to the inner walls of the pipe, which will cause blockage.
In addition, violation of the recommendations-requirements can lead to an increase in noise, as well as knocking out hydraulic seals, preventing the release of harmful sewer gases into residential and industrial premises.
Tabular data and calculation examples
The correct slope of the sewer
For horizontal pipelines, as well as for specialized facilities, the slope is calculated separately, specific for each object according to a special formula. However, for apartment and private houses, it is allowed to use ready-made recommendations, which are indicated in the SNiP in the paragraph on the values \u200b\u200bof the slope of sewer pipes.
| Pipe diameter, mm | slopes | m/r.m |
|---|---|---|
| maximum | minimal | |
| 50 | 0,035 | 0,025 |
110 | 0,02 | 0,012 |
150 | 0,01 | 0,007 |
200 | 0,008 | 0,005 |
As can be seen from the table, each diameter has its own recommendations. For clarity, consider one diameter in more detail.
Find out the angle of inclination for a diameter of 50 mm. The table shows the following values: 0.035 and 0.025, which means that on a segment of 1 meter, the height difference along the horizon between its ends is 35 and 12 mm, where the first value is the maximum allowable, and the second is the minimum.
Knowing these values, it is easy to calculate numerical values for a pipeline of any length. For example, the length of the horizontal outlet between the extreme receiver to the kitchen (sinks) and the socket of the riser is 4.5 running meters.We multiply the value of the length by the difference in the horizontal difference for 1 meter, we get: 4.5 (lin.m) * 0.035 (m / rm) = 0.1575 (m) - max, 4.5 (lin.m) * 0.025 (m/rm)=0.1125 (m) – min.
Thus, the interval was from 11.25 cm to 15.75 cm. This means that for laying a K. branch with a diameter of 50 mm with a length of 4.5 m, a slope of 11.25 to 15.75 cm is acceptable. A more suitable value is selected, marking is made and the required branch is mounted.
Slope check and control
Expose correctly
It should be repeated and noted the importance of observing the parameters of the slope of the sewer pipes, since this is the main circumstance, which will avoid both blockages and stagnation of wastewater inside the compressor station.
To facilitate the installation of CT, as well as to check the work performed, there are special devices: building levels (laser, bubble). It is convenient to use the laser level to mark and control the installation of internal wiring, but it is impossible to use it for work with external sewage.
For the construction of an external CS, the bubble building level is more suitable - it only needs to be slightly modified, i.e. give it the right angle. This is done using a thin board, which, to give the desired slope, is attached to one side of the tool with adhesive tape. Now nothing will prevent you from setting the CT with the desired slope, as well as checking the correct installation by the contractor and being sure of the proper operation of the sewer for a long time.
Selection of pipe diameter and its conductivity
The correct operation of household K. is also achieved by observing the requirement for the pipe to be filled with drains. According to technical standards, the K-pipeline should not be completely filled - empty space must be left for the removal of K-gases, as well as to stabilize the pressure inside the system.
Filling formula
The thinner the pipe the more space for the removal of harmful gases must be left in the CS.
In addition to venting, empty space allows you to increase the bandwidth of the t-wire.
The table below shows the recommended values for the maximum filling of the t-wire with sewage. As you can see, this indicator is directly related to the diameter - the larger it is, the more the pipe can be filled.
These figures are valid for both internal and external sewers.
| Diameter, mm | Max. filling, % |
|---|---|
| 50-150 | 0.5 |
150-250 | 0,6 |
250-450 | 0,7 |
450-900 | 0,75 |
from 900 | 0,8 |
It should be mentioned that these recommendations are used only for domestic systems. In industrial wastewater disposal and at specific facilities, their own standards apply, and the values \u200b\u200bare calculated for each case separately.
Optimum speed of "mud" masses
Optimum sewage discharge rate
The hydraulic slope of the CT, calculated and tested over the years, contributes to the efficient passage of waste. If the correct angle of inclination is observed in the channel system, an optimal flow rate is created for this. In the technical literature, it is called "self-cleaning speed".
The closer it is to the recommended indicators, the better for the K.-system as a whole. It is calculated according to a special formula, and directly depends on the diameter of the pipe and its slope. However, for apartment buildings, private households and country cottages, these calculations are optional. For these cases, in SNiP, values of an informative nature are given. The table below shows the approximate ratio of the diameter of the pipe installed at the recommended slope and speed.
| Pipeline diameter, mm | Self-cleaning speed |
|---|---|
| up to 150 | 0.65 |
150-250 | 07 |
300-400 | 0,8 |
450-500 | 0,8 |
600-800 | 1 |
Installation of K.pipeline 110 mm external sewage
It was previously considered that, according to the technical regulations, each pipe diameter has its own slope value. For a 11 Ohm pipe, this value is from 0.012 to 0.02 m per 1 linear meter.
Installation of external sewerage
The external sewerage system of a private house is non-pressure, the flow movement occurs by gravity at a self-cleaning speed of about 0.65 km / h, with a maximum filling level of a plastic pipe by 50-55%.
At the beginning of the installation, the upper reference point is determined - the exit from the house of the sewer riser. An external K. branch should be laid below the freezing point of the soil - it must be completely below this mark.
Entrance to the sewerseptic tank) is calculated according to the zero point (connection to the riser) and the height difference, calculated taking into account the requirements of the technical regulation, - the length of the external outlet, multiplied by the tabular value of the slopes of the sewer pipelines.
Throughout the external sewerage, technical channels (revisions) should be equipped, closed with covers on threaded connections, - at the rate of: one revision per 10 meters. With a complex construction of the highway, with multiple changes in direction, revisions are mounted at each turn.
Read also: Projects of country houses for 6-10 acres: 120 photos, description and requirements | The most interesting ideas Conclusion
Internal sewerage, pipeline laying
Summing up, it should be repeated about the need to follow the recommendations formulated in the SNiP, otherwise in the future you may encounter undesirable consequences - frequent sewer blockages, leaks, fetid smell in the house.
To get acquainted with the theoretical part related to the arrangement of internal sewage, its elements, it is recommended to watch the following video material.
Video: Laying sewer pipes - Slopes, connections, diameter and more
Sewer pipe laying - Slopes, connections, diameter and more
What slope of the sewer pipe should be in a private house or apartment? | Description for pipes with a diameter of 50, 110, 160 and 200 mm [Instruction]
