Cast iron sewer: installation methods, pipe size, service life

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Cast iron sewer: installation methods, pipe size, service life
Cast iron sewer: installation methods, pipe size, service life

The appearance of the cast-iron sewer is not very attractive. As a rule, such structures were installed in the bathrooms of typical houses from the times of the Soviet Union. Many associations are with such houses. But do not underestimate the sewers of this type. Yes, it is not very attractive, but it is very reliable. And this is not the only plus. Of course, it also has disadvantages, and sometimes they turn out to be significant. Let's try to understand in as much detail as possible with all the nuances of sewage from cast-iron pipes.

Key Features

Sewerage is a system of pipes that are made of cast iron or any other material. Moreover, it can be both an external and an internal network. It also happens that certain types are used only for the manufacture of a small part of the system, for example, a riser. In a cast-iron sewer, pipes are made of gray metal. In its manufacture, the centrifugal casting technique is used. In order to protect these pipes from corrosion, they are covered with bituminous mastic on both sides.

Pros of cast iron pipes

Of course, these pipes are very much inferior to plastic ones. But they havethere are positive characteristics, among which:

  1. Compared to other metals, cast iron pipes are less prone to corrosion.
  2. The material is not combustible, heat resistant.
  3. Resource of products for over 50 years. With gentle maintenance, pipes can last 80 years or more.
  4. Very high noise isolation.
  5. Withstand any temperature without problems.
cast iron sewer

And the disadvantages?

But there are also disadvantages that affect the popularity of this type of sewage:

  1. Quite high cost.
  2. Due to the large weight, the process of installing sewer pipes is complicated.
  3. Cast iron is a fairly fragile material, so it is extremely important to follow all precautions when working with it. One careless move and the pipe will become unusable.

Types of cast iron pipes

In total, two types of cast iron pipes can be distinguished, which differ from each other in the method of connection. Firstly, these are socket-type pipes, the most familiar to us. At one end they have a bell, that is, a slight expansion. There are no protrusions on the second end. Due to this design, it turns out that the smooth edge of one pipe can be easily installed into the socket of the second. This connection looks nice, but it is much more difficult to maintain.

Secondly, these are socketless pipes that are connected using special clamps. If an internal cast-iron sewerage is performed using them, then it is necessary to mask the joints. But most importantly, service andrepairing such a system is much easier to do, even with your own hands.

cast iron fittings

It is necessary to pay attention to the fact that regardless of the type of connection of sewer pipes, the junction is the most dangerous, as blockages and other problems usually appear in it. For this reason, inspection hatches must be made next to such sections on the pipeline. In the case of external sewer networks, the functions of the inspection hole are transferred to manholes.

Connection types

Besides the fact that there are differences in the way the pipes are connected, they also differ in diameter. For use in residential buildings, 3 sizes are usually used:

  1. Diameter 150mm, wall thickness 5mm. These are used when they are under high load.
  2. Cast iron pipe 100mm, wall thickness 4mm. These are usually used to make risers that come from the toilet.
  3. Diameter 50mm, wall thickness 4mm. Usually installed to divert drains from sinks and washbasins, as well as other sources.

It is extremely important when selecting pipes to take into account both the standard size and the method of connection. Check product quality. Be sure to pay attention to these points:

  1. There must be no sinks, holes, or other defects on the inner and outer surfaces.
  2. Look at the section of the pipeline, you can understand from it what kind of granularity the material has. It should be even and shallow.
  3. The wall thickness should be even - this is one of the most important indicators, according towhich can identify a quality pipe.

How pipes are installed

In fact, pipes made of cast iron are currently extremely rarely installed in country houses, as they have many shortcomings. We talked about them above. In particular, if you decide to install the sewer system yourself, it is simply unreasonable to use cast iron pipes. First, you need rich work experience. Secondly, it is much more difficult to lift and mount pipes on your own, you will have to look for help.

cast iron sewer tee

Installation of cast-iron pipes is not much different from the installation of plastic or asbestos. It is necessary to make markings in places where pipes are planned to be installed. If you are doing a floor screed, leave a place under the tee extending from the riser. This must be done in order to subsequently avoid violating the integrity of this very tee during upsetting. You also need to decide how the pipe will be fixed on the wall.

The easiest option is clamps that need to be installed on the pipeline below the pipe junction. In this case, it is necessary to remove adjacent fasteners from each other by 1-2 m, if the riser is vertical. If the pipes are horizontal, then the distance should correspond to ten times the diameter.

Using clamps, you can make both rigid and non-rigid connections. In the first case, metal clamps must be tightened as tightly as possible. Between it and the pipe you need to install a rubber gasket. In the second case, the gasket is not used, and the clampdoesn't tighten all the way. In both cases, you will avoid creating excessive stress in the pipes.

It is extremely important to maintain the distance from the riser to the wall - it should be about 40 cm. But there is another method of fixing the pipe, while they are hidden inside the walls. It is necessary to make strobes in the walls according to the marking. These are channels whose width is slightly larger than the diameter of the pipe. In this case, you can avoid the appearance of excessive stress in the walls of the pipes. Immediately before laying in this groove, it is necessary to wrap the entire surface with soft material.

If necessary, the pipes are wrapped with a heat insulator. Now it is allowed to apply plaster on the wall to mask the strobe. In this case, you hide the sewer from prying eyes. After choosing the method of fastening, you can proceed with the installation. At the first step, you need to prepare the entire system, fix the clamps or make strobes. In the second step, you need to collect the entire pipeline. The connection method directly depends on whether pipes are used with or without sockets.

cast iron sewer connection

How to connect pipes? Basic Options

In order to perform a socket connection, you need to follow this sequence:

  1. Twist 80mm resin tape into a bundle. Use it to wrap the smooth edge of the pipe.
  2. Then, with the previously wrapped end, you need to install the pipe into the socket of the other.
  3. Using a narrow wooden spatula and a hammer, you need to drive the tourniquet into the socket so that this seal occupies at least 2/3 of the connection.
  4. Make sure the gap is the same between the socket and the pipe installed in it.
  5. It is necessary to fill in the sealant from above - it can be either sulfur or cement, asbestos cement.

The last two solutions are used if you need to make the most rigid connection. It is worth noting that it is highly desirable that the winding does not get inside the pipe. This will immediately lead to clogging.

As for the socketless pipe, the differences are only in the type of connection, it is carried out using a strong steel clamp. A cuff is inserted on its inner surface. The pipes must be joined to each other, and the joint must be fixed with this clamp. To date, plastic pipes are more often used for the manufacture of systems in houses, they are much easier to mount. But in old houses, cast-iron sewers are still used. Therefore, if you decide to install plastic, you must first dismantle.

How to cut cast iron pipes

Sometimes you have to cut cast iron pipes. To do this during repair or installation, you will need to follow a certain algorithm. To do all the work as accurately as possible, you need to get goggles, a marker, a hacksaw and blades, or a saw with a chain clamp. The cutting procedure is as follows:

  1. First, let's look at how cutting is done with a chain clamp saw. First, mark the cut line with a marker or chalk. It is imperative that all lines are straight.
  2. Wrap the pipe with a chain. trydo it right too. It is necessary that the maximum number of discs be located on the surface of the pipe.
  3. Now you need to press the handles so that the saw wheels cut into the surface of the pipe. Please note that you will most likely have to do this more than once in order to completely cut the pipe. It may also need to be rotated a bit.
  4. Similarly, cut in all places that were previously marked.
service life of cast iron

You can use a hacksaw. To do this:

  1. Place the blade (long) in the unit and fix it. Typically, blades have carbide or diamond inclusions that allow easy cutting of hard metals.
  2. Designate the places where you need to cut the pipe. Keep the lines straight and fix the pipe firmly in place. Ask someone to support her while cutting.
  3. Cut with a hacksaw. If this is a 100 mm cast-iron pipe, then it will not be difficult to cut it. After all, it has a wall thickness of only 4 mm (the 150th has 1 mm more, so it will take a lot of effort).

What nuances to consider when connecting cast-iron socket pipes

internal cast-iron sewerage

Very often, when installing sewers, pipes are used that have a socket at one end. If you decide to use them, then you will need to do the following manipulations:

  1. First, clean the flare and the edge of the second smooth pipe so that there is no contamination.Pay attention to whether there are defects or other foreign objects on the pipe.
  2. Install the (smooth) end of one pipe into the socket of the second.
  3. Now you need to increase the tightness of the connection. To do this, you will need to hammer the tow inside the bell. Take care not to get material inside the pipe. But the procedure for connecting the cast-iron sewer is not over.
  4. Next, you need to fill the rest of the space with cement mortar. It is recommended to use only the M300 or M400 brands. Cement is diluted in water in a ratio of 9 to 1.
  5. The solution is poured into the socket, after which the joint is covered with matter (preferably wet). Please note that silicone-based sealant can be used instead of cement, and bituminous mastics can also be used.

The nuances of connecting smooth pipes

As we noted earlier, they are connected using special couplings, crosses, bends. Such cast iron fittings can be found on sale. The connection method depends on many parameters, including the diameter. But still, the most popular option is the clutch, which can be of several types:

  1. Cylindrical. This is used if the pipes are of the same diameter. There is a thread inside the coupling.
  2. Futorka is used for heating systems, in fact, it is the same cylinder, but it also has an external thread.
  3. Two cylinders - this type of connection is used if it is necessary to join pipes of different diameters. The cylinders also have internal threads.

If there isnecessary, then a cast-iron tee is installed for the sewer. It allows you to connect several sources of waste to the riser.

cast iron pipe 100

The process of docking is not very complicated, first you have to outline how far the pipes will enter the coupling. Please note that the joints must be clearly in the middle of the coupling. After that, you can install pipes. Silicone or bituminous compounds can be used to improve tightness. There are also other devices for connection - these are saddles, tees, crosses, various cast-iron fittings. So, it is not difficult to choose the right option.

How to connect plastic and cast iron pipes

Very often during repairs there is a need to join a plastic pipe and cast iron. Of course, you can simply insert one into the other, and fill the connection with cement. But the plastic will begin to deform. This will cause a leak to appear. It is extremely important that the docking site is sealed very carefully. After all, different materials are used, they expand differently with increasing temperature. Consequently, depressurization will appear, followed by a leak. Because of this, the service life of the cast-iron sewer is reduced. In some cases, systems even have to be completely redesigned.

In total, there are two ways to join cast-iron and plastic pipes. The choice depends on whether there is a bell or not. Let's say you have a socket in your sewer system, so it's enough to purchase a special adapter. It is you who can easily install it in the socket. Atadapters have a diameter similar to that of standard pipes of the sewer system. If necessary, you can even buy non-standard adapters. It is installed in a pre-cleaned socket, it is advisable to coat it with silicone sealant. And then this adapter needs to be put in a plastic sewer pipe.

cast iron sewer line

If there is no socket in the sewer system, you will have to use two adapters of different diameters. A rubber adapter is put on a cast-iron pipe. The surface of the pipe must be thoroughly cleaned and contaminated. A plastic one is put on top of the rubber adapter. The sewer pipe must be installed just in it. But do not forget that all connections must be treated with a sealant. This will prevent not only leakage, but also an unpleasant odor.

That's it, pipe joining is complete. By the way, such a connection is very easy to disassemble if necessary. As you can see, the installation of cast iron sewer pipes is quite simple, but you will have to do the work in a team.

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