Connection of sewer pipes. What are the types of sewer pipe connections depending on the material used for the pipeline? It is better to connect sewer pipes

Sewer adapters are special parts for pipeline installation that make it possible to vary the direction, diameter and materials of the communication system. The presence of sewer adapters greatly simplifies the partial replacement, installation and repair of sewer systems.

Modern sewer lines are in the vast majority of cases installed from polymer pipes. Depending on the layout, the sewerage system has a distribution throughout the building, which is connected to a common drain and discharged outside.

The pipeline configuration has many straight sections that are interconnected into complex systems with turns, bends, tees, crosses, plugs and revisions.

When assembling the pipeline, sewer adapters made of polymer materials are used. They can be either removable or soldered.

Old buildings are equipped with sewer pipelines made of cast iron, less often made of steel. To repair, partially replace or insert a separate apartment with a plastic sewer system, it is necessary to combine pipes made of metal alloys with pipes or fittings made of polymer materials into one system.

Here adapters also come to the rescue, which are made with special different ends and allow you to reliably connect dissimilar communications. Plumbing sewer adapters are designed for:

connections of straight sections of pipeline with different diameters;
connecting pipeline sections made of different materials (the diameter can be either the same or different from each other);
creating the necessary configuration of the sewer section (turns, bypass, routing).

Note! Before purchasing sewer adapters, you should know not only the required material and diameter, but also the type of thread - external or internal.

Basic properties and types of adapters for pipes made of different materials

To select the necessary adapters, you should know what the plumbing market offers and how they can be used. There are two groups of sewer adapters:

concentric – intended for installation on vertical sections of communications;
eccentric - installed on a horizontal pipeline.

Old and bulky cast iron pipelines can still be found in many apartments. But no matter how reliable they may seem, sooner or later their service life comes to an end. An excellent solution would be to completely replace cast iron with plastic, but, unfortunately, this is not always possible.

Some are stopped by the financial side of the issue, others are unable to come to an agreement with their neighbors. It is in such situations that the need arises to connect plastic and cast iron sewer sections. There are several methods that allow you to carry out such work quickly, efficiently, and without the involvement of professional help.

The entire complex of work can be divided into four stages:

Preparing the work site and the necessary tools.
Dismantling of the old pipeline.
Installation of plastic pipes.
Connection of elements.

To make the connection between a plastic pipeline and a cast iron pipeline reliable and durable, you should prepare all the necessary tools and materials in advance:

A special hammer with a rubber or wooden head. An ordinary iron hammer will not work here, since it can easily damage cast iron, which is so durable in appearance but very sensitive to impacts.
Cutting tool. This could be a grinder or a hacksaw.
Adjustable wrenches.
Depending on the chosen connection method, you may need a hand press, thread cutter or welding machine.
Plastic pipes of suitable size. To connect the toilet to the riser, you will need elements with a diameter of 110 mm; for laying pipes to the bathtub and sink, plastic with a diameter of 50 mm is best suited.
Necessary adapters, gaskets, couplings, seals, sealing agents.

Note! Installation of a plastic pipeline must include inspection hatches. Neglecting this rule will significantly complicate repair work if the need arises.

Dismantling an old pipe

The cast iron pipeline must be dismantled very carefully to prevent chips or cracks.

If you are faced with the need to lay a sewer system and you don’t know how to connect sewer pipes, don’t worry: remember your childhood and play... with a construction set.

The fact is that modern pipes for these purposes are made of PVC (plastic, in other words). And for ease of installation, they are produced in strictly defined diameters and lengths. Well, since pipes are not always laid strictly straight, you can find swivel fittings for them in any store selling such goods. All this is very reminiscent of a children's construction set, since the elements of the sewer system, if you don’t delve too deeply into the process itself, are simply inserted into each other. As a result, you get a strong and reliable connection that does not leak, does not transmit unpleasant odors and can serve you for a long time without replacement or repair.

Fitting

But let's get back to the fittings. Fittings are additional elements to pipes that help connect them into a single structure. It is customary to distinguish fittings depending on:

structures - turn signals (angles), tees, couplings, extensions, plugs, etc.;
purposes – connecting and intermediate;
shapes - L-shaped, T-shaped, straight.

Do not think that all the fittings listed above in the classification are different elements. In fact, the same fitting appears in each line of the classification under a different name. Take, for example, a coupling that is used to connect two sewer pipes. By design this fitting will be simply a “coupling”, by purpose it will be intermediate, by shape it will be straight.

Based on this classification of fittings, it is much easier to imagine what exactly you need to connect the pipes into one structure.

We assemble a sewerage system for a house or apartment

Before you figure out how to connect sewer pipes, you should understand the principle of assembling the entire sewer system.

So, all work should begin with creating a drawing on which you should depict your future system. Take a piece of paper and draw on it schematically all the plumbing fixtures that need to be connected to the sewer (sink, toilet, shower or bathtub, etc.).

Then connect them with lines to the main sewer riser. Each line is a pipe. The pipes will be connected to each other using fittings.
Please note that sewer pipes in a house usually have only two types: with a diameter of 50 and 110 mm. Fifty millimeter ones are designed to drain waste from sinks, sinks, bathtubs and showers, as well as from washing machines and dishwashers. If there are too many plumbing fixtures on one line, then it is better to increase its diameter to 110 mm, otherwise you will often have problems with blockages.
But the toilet is connected only through a pipe with a diameter of 110 mm, while the connection itself to the plumbing fixture is usually made using a flexible corrugation, which is inserted into the sewer pipe.

Having figured out what elements your sewer system consists of, you can go to the store. Since it is almost impossible to damage sewer pipes when working with them, you should not purchase components in excess. The main thing is not to forget that each pipe at one end has an extension into which another pipe will be inserted. If you cut a long pipe with a hacksaw (the cut must be strictly perpendicular) into two parts, then the second element will not have such an expansion, and to connect it to another pipe or fitting you will first need to install a coupling. In this case, the cost of different sets of pipes (one with a coupling or two short ones) will be approximately the same.

The first in the sewerage system will be a turning fitting, to which you will connect a flexible hose of a plumbing fixture (siphon) on one side, and a pipe on the other. You can, of course, do without this fitting by connecting the siphon directly to the pipe, but in this case, if the joint is not airtight, there is a possibility of the joint leaking.
When inserting a pipe into a fitting (or vice versa), be sure to observe two conditions:

a rubber gasket must be placed at the joint (it is sold as a set);
the pipe must fit into the fitting (or into another pipe) to its full possible depth.

Next, in places where other plumbing fixtures are connected to this pipe, tee fittings are installed. If you need to connect pipes of different diameters, use a special adapter fitting.
When assembling the sewer, do not forget about creating the necessary slope of the pipes, otherwise your system will not provide liquid drainage.
Assembling the system must move from the plumbing fixtures to the main riser so that the flow of water is not interfered with by the joints.

External sewerage

Unlike intra-house or intra-apartment sewerage, external sewerage (laid along the local area) is assembled without rotary fittings. It is recommended to install wells instead - they will make cleaning easier. After all, all the pipes will be hidden in the ground and digging them out every time they become clogged is quite difficult, and cleaning them through fittings that go to the surface of the earth is not always possible.

Of course, pipes for external sewerage have a larger diameter than pipes in the house.

Each of them cutting into the outer pipe increases its diameter by one size.

If the outer pipe is common to two others with a diameter of 110 mm, then its diameter should not be less than 160 mm; for three pipes of 110 mm each - with a diameter of at least 200 mm. This rule applies to small buildings, provided that the distance to the nearest sewer does not exceed 30-40 meters. In other cases, the outer pipe must have a larger diameter in order to work “with a reserve”.

Video

Most often, during the installation of sewerage, it is necessary to connect pipes of different diameters. Therefore, we invite you to watch a useful video covering this issue:

Drainage systems in private houses and apartments are increasingly made from various polymers. The low price and light weight, combined with the ease of installation of plastic pipes, provide them with well-deserved popularity. If you can connect plastic pipeline elements to each other in many ways, then if it is necessary to replace part of the network, when plastic pipes are connected to old cast iron ones, only a socket connection is suitable.

Plastic is one of the cheapest materials used to make consumables for sewerage equipment. When laying communications in a private house or apartment, price can become the determining parameter in the choice of pipes.

Besides being cheap plastic has other advantages:

light weight, which simplifies the delivery of pipes and fittings and installation of the pipeline;
the ability to choose the type of plastic and connection method suitable for a particular case;
the smoothness of the walls and the chemical inertness of the polymers, due to which no build-up is formed on the inner surface and the throughput of the pipeline does not decrease during operation of the sewage system;
compatibility with other materials - you can not only assemble a sewer entirely from plastic, but also replace part of the old pipeline with polymers, since there are special connecting elements for combining plastic with pipes made of metal alloys;

However, the installation of a sewer pipeline made of polymer products has its own characteristics:

plastic is afraid of ultraviolet radiation, so plastic sewers must be hidden from direct sunlight;
despite the elasticity characteristic of polymers, most pipes cannot be bent; to change the direction it is necessary to use bend fittings;
sewerage consumables are made from polymers that have different limits of high-temperature exposure: polypropylene (80º), polyethylene (50º) and polyvinyl chloride (40º), the pipe material should be selected based on the maximum temperature of the wastewater;
for internal and external sewerage, pipes are made with different strength indicators, which for convenience are painted in different colors: gray for internal or apartment pipelines, orange for external ones;
when laying a deeply buried pipeline in regions with a deep level of soil freezing (more than 2 m), pipes with a corrugated outer surface are used;
indoors, thin-walled corrugated pipes are used to connect household and plumbing appliances;
Since the operation of the sewerage network requires a slope of 1-3%, allowing wastewater to move by gravity, sewerage in an apartment is assembled from the riser to the devices, in a private house - from the outlet pipe to the devices, and on the street from the outlet pipe to the collection or discharge point drains;
network elements are fixed to the walls with fastening increments of 8-10 pipe diameters to prevent sagging and deformation of the pipeline;
Even entire units made of polymer products are lightweight, so it is convenient to assemble large parts of the drainage network and connect them to each other once assembled.

Sewage is an integral part of the communication systems of houses and apartments. The design of the outlet pipeline is not complicated, but its reliability and durability are directly related to the quality of the connections of the elements into a single frame.

In order to correctly connect sewer pipes, operating principles for various types of elements are studied, and simple rules of work technology are followed.

Main types of joints of pipeline elements

Types of pipe connections depend on the material of the elements, but can be divided into two large classes:

Detachable types include:

Threaded method;

Socket connection of pipes.

One-piece joint options are used in structures that operate under pressure. In this case, the pipeline must be a single structure with a strong connection of all elements. The main methods of permanent connection include:

Use of special glue.

The first type is used to make a frame made of steel and cast iron, less often for polymer elements. The second option was created specifically for PVC pipes.

The socket connection is the simplest and most convenient for most types of pipes. This fastening is suitable for plastic, cast iron and ceramic elements. Making a socket connection does not require extensive experience and skills.

To connect elements with different cross-sections, special adapters for sewer pipes of different diameters are used. Such devices help to transition branches from plumbing fixtures and small-diameter devices to the main sewer pipe with a cross-section of 100 - 150 mm. When working with pipes made of different materials, special adapters are used to ensure reliable fastening of elements of different weight, strength, hardness and flexibility.

Making a pipeline from plastic pipes

Connecting sewer plastic pipes can be done in several ways, the most common of which is the use of a socket and special adhesives. Heat treatment and threading are sometimes used when assembling a PVC frame, but the material of the elements itself does not involve working under excess pressure, so such technologies are used much less frequently.

Plastic sewer rings can be used to create storage tanks and wells. Their connection to the pipeline is carried out by adapters or corrugated pipes.

Using a bell

The installation of the pipeline is simple and involves joining with a socket and rubber seals. The method is suitable for any type of pipe, but is most common when assembling a structure from plastic elements.

The socket is a section of increased diameter at the end of the sewer pipes being connected. The elements of such fastening are rubber sealing cuffs and rubber O-rings. Seals allow you to hermetically connect the structure and ensure its operation without leaks at slight excess pressure.

Connecting sewer pipes with your own hands using a socket does not require special experience or skills.

To connect sewer plastic pipes, the smooth end of the element and the socket are cleaned of dust and dirt. Next, the socket is inspected for the presence of a rubber seal, which ensures reliable fastening and tightness of the joint. If there is no ring, a sealing collar for sewerage or rubber O-ring seals are selected for the smooth part of a smaller diameter according to the size. The cuff ensures a tight connection of the pipes and withstands the flow of wastewater under excess pressure.

The seal is placed in the socket. The smooth end of the second pipe is lubricated with silicone grease or liquid glass and inserted into the socket until it stops. A mark is placed on the surface, and the element is pulled back by 1 cm. This technology involves a tight cuff around a pipe of a smaller diameter.

Using polymer glue

Depending on the difference in the diameter of the joined elements, as well as their operating conditions, various adhesive compositions are selected. The simplest method involves the use of glue when using a socket joint. Fixing with glue performs the functions of fastening, sealing and sealing, so installing an additional rubber ring is not required. PVC sewer pipes should be connected according to a specific pattern.

Before applying the glue, the edges are thoroughly cleaned of dirt and degreased. Next, the adhesive composition is applied, and the pipes are securely fixed within 10 - 15 minutes. The joint is additionally sealed with one or two more layers of glue.

Connecting sewer plastic pipes of the same diameter requires the selection of a special glue and a different method of fixation. In this case, adapters are used to make a reliable connection. The adapter serves as the bell. The technology is complicated by the need to repeat all manipulations for both pipes, as well as additional sealing of both joints.

Thread and welding

You can connect plastic sewer pipes using other methods. There are special welding techniques, as well as the possibility of using threaded fasteners.

Special equipment is used for welding. The device heats the polymer at the ends of the elements to a mobile state. Next, the pipes are pressed against each other so that the molten plastic creates a single mass at the junction, and are fixed until the material cools. After cooling and re-polymerization, a layer of polymer is formed at the junction, combining the two elements into a single structure.

When using threaded fasteners for plastic, American technology is used. This connection involves the use of a nut or fitting and two threaded pipes. A fitting or nut securely connects the elements; an O-ring is used to seal the joint. The structure is dismantled by unscrewing the fastening fitting or nut without additional rotation of the frame.

Making a pipeline from steel elements

Steel is susceptible to the negative influence of wastewater. Its corrosion resistance is low, so its use is limited to sections of highways under highways and roads. Steel elements can withstand significant loads, so they are used in places where the pressure on communications is maximum.

The connection of steel sewer pipes is carried out by welding or threading. The first option requires the use of expensive equipment, because stainless steel is difficult to heat treat. Welding is used in the construction of communication highways. Pipelines for houses and apartments made of steel pipes require quick-release pipe connections.

The thread reduces corrosion of the material due to the absence of defects in the structure formed during thermal welding. Quick-release pipeline connections facilitate the repair and replacement of individual structural elements, provide reliable fastening and tightness.

Threaded fastening can be performed by directly joining two pipes with external and internal threads, or by the “American” method using a nut. The first option ensures that the pipeline operates under pressure, but requires additional sealing and good sealing. The American threaded connection is easier to perform and further work. Disassembling the fastener involves removing the fitting or nut without unscrewing the frame. The nut cover has an external thread, which increases the corrosion resistance of the structure.

Connection of cast iron pipes

Cast iron pipes are traditional elements of communications; they are highly durable and resistant to corrosion. For joining cast iron pipes, a socket or an American quick-release coupling is used.

The socket connection for cast iron elements becomes more complicated. The rubber seal is not suitable for cast iron, so the gap between the socket and the inserted pipe is sealed by hammering in flax tow. The fibers are compacted with a special wooden spatula, hammering and compacting the tow with a hammer. The material is laid and compacted until the compactor occupies about 65% of the volume of the socket.

Next, the remaining volume of the socket is filled with cement mortar to securely fix and seal the joint. When hardening, the solution requires additional moisture and protection from moisture loss, otherwise its layer will begin to crack and lose its tightness. Cement mortar can be replaced with special bitumen mastics, silicone sealants or asbestos-cement mixture. After completion of the work, the pipeline is fixed for several days to harden the sealant layer.

Threaded connection is used for small diameter pipes. This method makes it easier to work with cast iron elements and ensures reliable fastening of the structure.