Cast iron pipes are used today for laying external and internal sewage systems. Products can be channelless and channel. Their service life can reach 100 years. Connecting elements and assortment of sewer pipes are determined by GOST 6942-98. After reviewing the documentation, you can understand what parameters the pipes should have.
Dimensions and Diameters
When considering the dimensions of cast-iron sewer pipes, you should find out that today there are three units of sizes. They differ in cross section. The main types are SMU and SME. The first have smooth ends, the second one has a smooth end, and the second has a bell. Tubular products are marked with a nominal cross section.
Looking at the inscription, in the first part you will see the brand of material. The nominal section is indicated below. For example, if the marking is as follows: Dn 100, while the inner diameter is 100 mm, and the outer is 110 mm. Considering the dimensions of cast-iron sewer pipes, you should pay attention to products with a bell, which are divided into three classes. Each of them has its own wall thickness and is indicated by the letters A, B or LA.
From the table of sizes of cast-iron sewer pipes, you can find out that the products have an outer diameter ranging from 81 to 429 mm. And one of the main indicators - the conditional passage varies from 65 to 400 mm. As for the wall thickness, it cannot be different, and depending on this, the pipe belongs to class A, if the thickness varies from 7, 4 to 13, 8. When the pipe belongs to class B, the wall thickness varies from 8 to 15 mm but for an LA class pipe, the wall thickness is between 6.7 and 12.5 mm.
The weight of the pipe depends on the size. For example, if you have a Du50 pipe in front of you, then its mass will be 11 kg. The pipe DN 1000 will weigh 620 kg. Intermediate values of 40 and 25 kg are valid for pipes DN150 and DN100, respectively. But this mass is alleged. It may differ from the real one. Due to the impressive weight, cast iron products are sold in segments, the length of which varies from 0, 75 to 7 m.
When considering the dimensions of cast-iron sewer pipes, you should consider that you should not buy a product with a thick wall if the pressure in the system is low. This will reduce the cost of the purchase, as well as the cost of installation and transportation.
About the bells and their sizes
The sizes of the sockets of cast-iron sewer pipes are determined by the type of these parts of the products, which can be I, II, III and IV. The size and design of the type 1 bell differ from the rest. If the conditional passage is 50 mm, then the diameter of the bell is 55 mm. When the conditional passage increases to 150 mm, the inner diameter of the bell becomes 155 mm. The external diameters of the sockets will be equal to 90 and 202 mm, respectively.
In this section, you can also consider the dimensions of a cast-iron sewer pipe per 100 mm. The inner diameter of the bell will be 123 mm. With an increase in nominal bore to 150 mm, the inner diameter of the bell increases to 176 mm.
The main types and their features
The described products can be bell-shaped, socketless, pressure and pressureless. In many industries, pipes have been widely used, which are indicated by the abbreviation of SHCHG. As part of such a pipe, spherical graphite, it makes the product more elastic and viscous. Such pipes replace the analogue of gray cast iron. By properties, they can be equated to cast and forged steel. By mechanical characteristics, these pipes can compete with steel products due to the high coefficient of resistance to corrosion. Their service life is 8 times higher than their analogues. Pressure products can be used to work with aggressive substances. They perform well in winter. They are not afraid of frost.
Pipes are highly durable, which means that they can be laid under highways, the installation depth can be quite impressive. Such a cast-iron sewer pipe, the dimensions and GOST of which were mentioned above, may be a bell-shaped or have rubber seals.
Pressureless pipes and their properties
The composition of the material has plate graphite, so the products do not have the proper strength. For their manufacture, gray cast iron is used. Such pipes are installed in those systems where high loads are excluded. They can be mounted together with plastic pipes.
To obtain a reliable connection, you can use rubber cuffs. The main advantages of these cast-iron sewer pipes, the dimensions of which were mentioned above, include the possibility of use for the second time after the dismantling.
Socketless pipes and their properties
The material contains graphite. For greater strength, the inner walls of the pipe are coated with epoxy. This allows you to get rid of the formation of layering and siltation. Epoxy resin performs well in an aggressive environment and saves the material from corrosion and destruction. The table of diameters of cast-iron sewer pipes will allow you to understand what parameters the described products have. As for SML, which is also called socketless, it does not need to create additional noise protection.
The products meet the fire safety requirements, are able to withstand heat and have high strength. Clamps are used to connect system elements. This is due to the absence of sockets at the ends. Such pipelines first became known in the early 60s. In those days, engineers worked on the creation of new technologies and materials. Today, socketless constructions remain reliable and are considered a high-quality method of manufacturing systems whose butt joints are highly tight without the use of sealing materials. This is due to the absence of sockets.
The inner coating of products is very smooth, so they differ from their analogues in increased throughput. The absence of corrosion explains the high wear resistance. These products can function at any temperature, they show resistance to the effects of impressive differences. The pipe is easy to process, in addition, it contains graphite. Thanks to him, the strength of the material becomes quite impressive. The wall thickness does not change over the entire length.
Properties of bell products
These pipes remain popular today, despite the flood of the market with new materials. They are used in various industries, and their main advantage is an extended service life, which is especially true if we compare with other analogues. This is due to the fact that over time, steel begins to rust. The disadvantage is the fragility of cast iron. The complexity of installation is more complicated compared to other pipes. In order to eliminate the effects of corrosion, the products inside and outside are coated with bitumen.
Cost of pipes
The sizes and prices of sewer cast-iron pipes from the catalog can be found. For example, a pipe with a length of 2 m and a conditional passage of 50 mm costs 1091 rubles. A pipe with a nominal bore of 100 mm and a length of 2 m will cost 1765 rubles. If the conditional pass increases to 150 mm, and the length remains the same, then the price of such a product will be 3222 rubles. You can buy a meter-long cast-iron pipe with a nominal diameter of 50 mm for 978 rubles.
Features of installation and docking
During installation, special attention is paid to the docking of products. In order to achieve the perfect result, putty should be prepared without wood waste and impurities. Before filling the bell with a mixture of asbestos cement, it is necessary to fill it with a tarred hemp lock. Then it is rolled up with a tourniquet and caulked into the slot of the bell. Care must be taken.
The thickness of the tow should be greater than the width of the gap, the length should be such that the strand entered the bell 30 mm from the edge. To obtain a mixture of cement and asbestos, 400 Portland cement and asbestos fiber should be mixed. These ingredients are mixed in a ratio of 70 to 30.
Before use, the mixture is moistened by adding water in a volume of 12% by weight. Docking of molded parts with cast-iron pipes is carried out by the method of sealing cracks arising between the inner surface of the socket and the molded part or the end of the pipe. When installing the pipe, the direction of the socket must be provided in the opposite direction from the movement of the liquid.
Finally
At the peak of popularity today, plastic pipes. The scope of their use is wide, but when installing sewer systems, the leading positions are occupied by steel and cast iron products. They are wear-resistant, have good soundproofing characteristics, are durable and have an optimal tensile index, which is important for long-term operation.