What does ductile iron pipe k mean for water transportation

Ductile iron pipes.

In the grade, K8, K9, etc., represent the grade of the ductile tube, K refers to the wall thickness coefficient, the higher the grade, the greater the pressure, and the lower the grade, the smaller the pressure.

Abstract: There are many pipe materials, so what is ductile iron pipe? Ductile iron pipe is a kind of cast iron pipe, the main components of ductile iron pipe are carbon, silicon, manganese, sulfur, phosphorus and magnesium.

1. What does ductile iron pipe mean?

The essence of cast iron steel pipe is ductile iron pipe, because ductile iron pipe has the essence of iron and the performance of steel, so it is called. Graphite in ductile iron pipes exists in a spherical form, and the size of graphite is generally 6-7 grades. In terms of quality, the spheroidization grade of the cast iron pipe is controlled to be 1-3 grades, and the nodularization rate is 80%, so the mechanical properties of the material itself have been well improved, and it has the properties of iron and steel.

The characteristics of ductile iron pipe, after annealing, the metallographic structure of the nodular cast iron pipe is ferrite plus a small amount of pearlite, and the mechanical properties are good, so it is also called cast iron steel pipe. There is a certain amount of spherical graphite distributed on the ferrite and pearlite matrix, according to the nominal diameter and the requirements for elongation, the proportion of ferrite and pearlite in the matrix structure is different, the proportion of pearlite in small diameter is generally not more than 20%, and the proportion of large diameter is generally controlled at about 25%.

2. What is the use of ductile iron pipes?

Due to the good mechanical properties of ductile iron pipes, excellent anti-corrosion performance, good ductility performance, good sealing effect, easy installation, mainly used for water supply, gas transportation, oil transportation and so on in municipal, industrial and mining enterprises.

Ductile iron pipe for oil is mainly used for drilling oil and gas wells and oil and gas transportation. It includes oil drill pipes, oil casings, and pumping pipes. Oil drill pipe is mainly used to connect drill collars and drill bits and transmit drilling power.

Oil casing is mainly used to support the well wall during and after drilling to ensure the normal operation of the drilling process and the whole oil well after completion. The pumping pipe mainly transports the oil and gas from the bottom of the well to the surface.

Ductile iron pipes are the lifeblood that keeps oil wells running. Due to the different geological conditions, the downhole stress state is complex, and the comprehensive action of tensile, compressive, bending and torsional stress acts on the pipe body, which puts forward higher requirements for the quality of the casing itself. Once the casing itself is damaged for some reason, it may lead to the reduction of production of the entire well disturber, or even scrapping.

Summary. The value represents the wall thickness grade, and the algorithm of wall thickness is e=k( where wall thickness is an important parameter for calculating weight; The wall thickness parameter of ductile iron pipe is k9, and the wall thickness parameter of ductile iron pipe fittings is generally k12

ductile iron pipes, is k-several.

The value represents the wall thickness grade, and the algorithm of wall thickness removal is e=k( where the wall thickness is an important parameter for calculating the weight; the wall thickness parameter of the spring imperial pin of the ductile iron pipe is k9, and the wall thickness parameter of the ductile iron pipe fitting is generally k12

Thank you for the wall thickness and pressure tolerance table?

There is no complete comparison between the nominal diameter and the outer diameter of the pipeline, and the conversion of the outer diameter to the nominal diameter basically depends on experience. The nominal diameter is approximately equal to the inner diameter. For example, the outer diameter of 108*7 is 108, and its nominal diameter is 100; Another example is 32*, the outer diameter is 32, and the nominal straight imitation clear missing diameter should be 25.

By analogy, we can get the correspondence between the outer diameter and the nominal diameter. Generally, the steel used for the Huai grip of the steel pipe is Q235, and the allowable tensile strength is [ ]215N mm2 (detailed "Steel Structure Design Code", after conversion, it will be found that 1MPa = 1N mm2) f (tensile force) = p (pressure) * load factor (detailed building structure load code) * r (inner radius) = f d (wall thickness) = p * When the pipe of DN100 is under internal pressure, its wall thickness d should be: D p*

1. The concept is different.

Machine-made cast iron pipe is a flexible interface drainage cast iron pipe produced by centrifugal pouring process, and the interface is generally W-type clamp type or A-type flange socket type.

Ductile iron pipe refers to the pipe made by high-speed centrifugal casting of centrifugal ductile iron machine after adding nodularizing agent to cast molten iron above No. 18, referred to as ball tube, ductile iron pipe and ductile cast pipe. It is mainly used for the transportation of tap water, and is an ideal material for tap water pipelines.

2. The performance is different.

Ductile iron pipes are a type of cast iron, which is an alloy of iron, carbon, and silicon. Graphite in ductile iron is in the form of spheroids, the size of the general graphite is 6-7 grades, and the quality requires the nodularization grade of the cast pipe to be controlled as 1-3 grades, so the mechanical properties of the material itself have been well improved, with the essence of iron, the properties of steel. The annealed ductile iron pipe has a metallographic structure of ferrite and a small amount of pearlite, and the mechanical properties are good.

The service life of the machine-made cast iron pipe exceeds the life expectancy of the building, excellent seismic performance, can be applied to the seismic fortification of high-rise buildings, and the flexible connection of flange gland and rubber ring or lined rubber ring and stainless steel clamp is adopted, with good sealing, allowing swing in the range of 15 degrees without leakage.

Metal type centrifugal casting, cast iron pipe wall thickness is uniform, the structure is dense, the surface is smooth, there are no sand holes, slag inclusion and other casting defects. The rubber interface suppresses noise and is irreplaceable for the quietest pipe, creating the most comfortable living environment.

3. Different uses.

Cast iron pipes are suitable for building drainage, sewage, civil engineering, road drainage, industrial wastewater, and agricultural irrigation pipelines; Cast iron pipes can be applied to large pipeline axial expansion displacement and transverse deflection deformation; Cast iron pipes are suitable for use in areas with a intensity of less than 9 degrees.

Graphite cast iron pipe is mainly called centrifugal ductile iron pipe, which has the essence of iron, the performance of steel, excellent anti-corrosion performance, good ductility performance, good sealing effect, easy installation, mainly used in municipal, industrial and mining enterprises water supply, gas transportation, oil transportation, etc. It is the first choice for water supply pipes, and it has a high cost performance.

1. The production process is different, ductile iron pipes are mainly produced by heating and annealing in the intermediate frequency furnace and then lined with cement and anti-corrosion on the outer wall, while machine-made cast iron pipes are not lined with cement.

2.The appearance is different, the length of a single ductile iron pipe is 6 meters, and the wall thickness is large; The single length of the machine-made cast iron pipe is 3 meters, and the wall thickness is thin.

3.Different uses, ductile iron pipes are widely used in municipal water supply and drainage, rural drinking water and outdoor fire protection engineering; The main purpose of the machine-made cast iron pipe is high-rise drainage and sewerage in the city.

4.The installation method is different, and the common nodular cast iron pipe is a flexible sealing ring slide-in connection; Mechanism drain pipes are mainly W type and B type, clamp connection and mechanical connection, inner gasket sealing ring.

The main components of ductile iron pipes are carbon, silicon, manganese, sulfur, phosphorus and magnesium. Executive standard GB T13295-2003ISO2531 2003

Ductile iron pipes are defined as pipes made by high-speed centrifugal casting of ductile iron pipes after adding nodularizing agent to cast molten iron above No. 18, which is called ductile cast iron pipes, referred to as ball tubes, ductile iron pipes and ductile cast pipes.

Ductile iron pipe is a type of cast iron pipe. In terms of quality, the nodularization grade of the cast iron pipe is controlled to be 1-3 (nodularity rate of 80%), so the mechanical properties of the material itself have been well improved, with the essence of iron and the properties of steel. After annealing, the metallographic structure of the anomalous cast iron pipe is ferrite plus a small amount of pearlite, with good mechanical properties, excellent anti-corrosion performance, good ductility performance, good sealing effect, easy installation, and is mainly used for water supply, gas transportation, oil transportation and so on in municipal, industrial and mining enterprises.

Hello, ductile iron is a kind of cast iron, adding a certain amount of magnesium or magnesium alloy to the molten iron, etc., so that the flake graphite in the structure becomes spherical, thus greatly increasing the strength, toughness and ductility. It is mainly used to replace steel casting parts for heavy machinery and agricultural machinery.

Hello, I hope the above can help you, thank you! Have a great day!

In the Code for Construction and Acceptance of Water Supply and Drainage Pipeline Engineering GB50268-2008, Part II Terminology Article clearly stipulates that water supply and drainage pipelines with working pressure greater than or equal are pressure pipelines.

In the title, "feed ductile iron pipes and connected pipe fittings are uniformly classified as pressure piping components."

Figure 1 and Figure 2.

The pipes made by using cast iron above No. 18 after adding nodularizing agent and passing through the high-speed centrifugal casting of centrifugal ductile iron machine are called "ductile cast iron pipes", referred to as ball tubes, ductile iron pipes and ductile cast pipes.

China's ductile iron pipe industry started in the early 90s of the 20th century, with the strong support of the China Urban Water Supply Association, the rapid development, after nearly 20 years of practical use, its safety and practicability have been widely recognized by the water supply industry, in 2008 the domestic annual output has reached 2.2 million tons, is 1990 times 11 times. Because China is a country with a shortage of water resources, there are more than 600 cities with water shortage, and more than 200 cities with serious water shortage.

1.Product standards.

GB T 13295-2003 Ductile iron pipes, fittings and accessories for water and gas pipelines.

GB T 17457-1998 General requirements for centrifugal lining of ductile iron cast iron pipe cement mortar.

GB T 17458-1998 Centrifugal method of cement mortar for ductile iron pipe cement mortar Composition inspection of lining fresh mortar.

GB T 17459-1998 Asphalt coating of ductile iron pipes.

GB T 17456 ductile iron pipe is sprayed with zinc.

GB T 17219-1998 Safety evaluation standard for drinking water transmission and distribution equipment and protective materials.

Resources.

Ductile iron pipe is a casting alloy developed at the end of the 40s of the 20th century. It is like spheroidal graphite cast iron produced by adding nodularizing agent and inoculant to molten iron. Because graphite is spherical, its mechanical properties greatly exceed that of gray cast iron, better than castable iron, infinitely close to steel, but lower than steel, and still have many excellent properties of ordinary gray cast iron, such as good castability, shock absorption, machinability and low notch sensitivity.

Therefore, ductile iron can be used for many important mechanical parts such as crankshafts, connecting rods, gears, valve bodies, cylinder liners, etc., to save steel and reduce costs.

Both ductile iron and ordinary cast iron contain graphite monomers, which means that cast iron is a mixture of iron and graphite. The graphite in ordinary cast iron is in the form of flakes, and the strength of graphite is very low, so it is equivalent to the existence of many flake voids in cast iron, so the strength of ordinary cast iron is relatively low and brittle. Graphite in graphite cast iron is spherical, which is equivalent to the presence of many spherical voids in cast iron.

The influence of spherical voids on the strength of cast iron is much smaller than that of sheet voids, so the strength of ductile iron is much higher than that of ordinary cast iron.

The performance of ductile iron is close to that of medium carbon steel**, which is much cheaper, and vermicular graphite cast iron is the best, but the expensive gray cast iron is worse, and the white cast iron is the worst. Therefore, the quality of ductile iron pipes with relatively good quality is better than that of other cast iron pipe fittings.