Ductile iron is a type of cast iron known for its impact and fatigue resistance, elongation, and wear resistance due to the spherical round graphite structures in the metal. Production of ductile iron is influenced by a large number of metallurgical, technological, heat transfer and designing parameters. Ductile iron marketing group from rough casting to finished products. The term pig iron arose from the oldfashioned method of casting blast furnace iron into molds arranged in sand beds in such a manner that. Oluwasegun abstractductile cast irons are materials having strength, impact toughness and ductility comparable to those of many grades of steel while exceeding by far those of standard gray irons. Austempered ductile iron castings advantages, production, properties and specifications abstract ductile irons, having a spheroidal or nodular graphite structure, are wellestablished engineering materials. The use of ductile iron has grown rapidly in the past 40 years, mainly through conversions from gray and malleable iron castings, steel castings, forgings and fabrications, and also through its use in new components designed with ductile iron. Ductile iron production practices karsay, stephen i on. Pdf analysis of ductile iron production on steel scrap base.
Magnesiumsulfur relationships in ductile and compacted. Soreltracy, quebec, canada abstract the formation of an oxide slag on the liquid bath is unavoidable during the processing of ductile iron melts. Mechanical and structural properties of ductile cast iron. G cast iron is defined as a high carbon containing, iron based alloy in which the graphite is present in compact, spherical shapes rather than in the shape of flakes, the latter being typical of gray cast iron. While dipra member companies have different names and locations, they all have one thing in common.
Austempered ductileiron castings advantages, production. This is the final part of the process and the one most people associate with foundries. Thermal analysis of ductile iron casting intechopen. While most varieties of cast iron are weak in tension and brittle, ductile iron has much more impact and fatigue resistance, due to its nodular graphite inclusions. Pure metals solidify with a solidification front that is very well defined and a clearly delineated solidliquid interface. It contains spheroid graphite in the as cast condition, through the addition of nucleating agents such as cerium or magnesium to the liquid iron 2, 4.
The ductile iron societys objective is to advance the technology, art, science of ductile iron production and to disseminate all such information to the members. The first step of the production of ductile iron cast. Figure 1 ductile iron manufacturing process3 refers to the figure 1 each of process will be explained further more below. Ductile iron s ease of maching and economy of production are almost equal to gray iron. Control of surface graphite degeneration in ductile iron for. Consequently, if ductile iron flanges are desired, that option must be so stated in the specifications and on the purchase order. Its strength, toughness and ductility duplicate many grades of steel and far exceed those of standard gray irons. It will be held at the hilton garden inn chicago ohare airport in des plaines, il. While ductile iron can be produced from steel or iron scrap, pig iron is the primary source of infeed for most modern ductile iron foundries. However, dipra recommends the use of ductile iron flanges on ductile iron pipe because of their superior strength and impactresistance. Willmans ductile iron foundry produces a family of cast graphitic irons that are high strength, resistant to shock, and with high ductility greatly exceeding standard grey irons and with properties similar to many high grades of steel, plus resistant to fracture even when bent, twisted or deformed. Effect of charge materials on slag formation in ductile. Ductile cast irons are materials having strength, impact toughness and ductility comparable to those of many grades of steel while exceeding by far those of standard gray irons.
The ductile iron used to manufacture the pipe is characterized by the spheroidal or nodular nature of the graphite within the iron. Recent development of ductile cast iron production technology in. Mechanical properties of sg iron with different matrix structure article pdf available in journal of materials science 365. Us20040042925a1 method for production of ductile iron. Ductile iron societyresearch committee report literature summary.
The primary objective of this guide is to assist producers of ductile iron castings in obtaining higher levels of quality reliability. The inoculation of grey and ductile iron is realized by the addition of small amounts of materials known as inoculants. While most varieties of cast iron are weak in tension and brittle, ductile iron has much more impact and fatigue resistance, due to its. The production of ductile iron is 3035% cheaper than steel and 34% times cheaper than nonferrous alloys and only 2030% more costly than normal grey iron. Pdf the costs for energy and materials in foundries are 40% of the total cost. Mar, 2010 a ductile iron pipe is produced with centrifugal casting method. Ductile iron data for design engineers revised edition. An inoculant is a ferrosilicon based alloy added to the molten metal either just before or during the pouring of the liquid iron into the mould. Dipra is a nonprofit association supported by all of the ductile iron pressure pipe manufacturers in north america. Ductile cast iron solidification is characterised by a very thin solidified skin and appearance of different phases. Recent development of ductile cast iron production. In addition, they have the same advantages of design flexibility and low. When used in place of grey iron, the design of the casting is lighter. Ductile iron what ductile iron is ductile iron is a family of cast graphitic irons which possess high strength, ductility and resistance to shock.
An inoculant is a ferrosilicon based alloy added to the molten metal either just before or during the pouring of the liquid iron. Ductile iron is also called ductile cast iron, spheroidal graphite cast iron, or nodular cast iron. In fact ductile cast iron provides a wide spectrum of mechanical. Ductile iron casting process could be reduced by implementing some.
Ductile iron is a high strength, tough material used in water and wastewater systems in all 50 states of the united states and in many other areas of the world. The term pig iron arose from the oldfashioned method of casting blast furnace iron into. Pdf processing techniques and productions of ductile. A recent development is to use an austempering heattreatment process to obtain improved combi nations of mechanical properties. The present invention relates to a method for nodularizing treatment of ductile iron using a ladle treatment method for nodularizing of a magnesium ferrosilicon alloy, where a magnesium ferrosilicon nodularizing alloy consisting essentially of 40 to 80% by weight of silicon, 2 to 15 % by weight of magnesium, 0,3 to 5 % by weight of lanthanum, 0 to 6 % by weight of calcium, 0 to 5 % by weight. Pdf production of ductile iron using indigenously manufactured. Enlighten those considering ductile iron production to the controls and tests required guide long time producers toward higher levels of quality reliability and.
The quality of the products vary according to the chemical constituents and physical microstructure of the casting materials. The outer skin is formed being very thin in ductile iron. Ductile iron, also called ductile cast iron, spheroidal graphite iron, or nodular. Ductile iron castings foundry and supplier carson castings. This type of pipe is a direct development of earlier cast iron pipe, which it has superseded. Modern cored wire injection 2pe9 method in the production. Both types of iron are strong, durable and good for machining into new shapes.
In the present scenario, where the selling price of products, especially ductile iron products, are not increasing so rapidly, the only way to cope. Ductile iron pipe is a pipe made of ductile cast iron commonly used for potable water transmission and distribution. The molten ductile iron is poured into a rapidly spinning watercooled mold and centrifugal force results in an even spread of iron around the circumference 1. Continuous testing and field experience have brought the production and use of ductile iron pipe to maturity. Improving ductile iron production using ultralow additions of magnesium. We produce all standard grades of ductile iron including 654512, 805506, and 1007003 as well as austempered ductile iron, and customer specific grades. Ductile irons ease of maching and economy of production are almost equal to gray iron.
Production of ductile iron castings without feeders. Annealed cast ductile iron can be bent, twisted or deformed without fracturing. Ductile iron society research committee report compiled by. Ductile iron finds application as a substitute for steel, malleable iron and nonferrous alloys. One third of the ductile iron production is for water pipes, another third for automotive parts and another for general castings. Di pipes fittings manufacturing business opportunity ductile iron pipe fittings ductile iron pipes are available in a range of diameters from 80mm to 1600mm and are suitable for both pot. Unlike gray iron, which contains graphite flakes, ductile iron has an ascast structure containing graphite particles in the form of small, rounded, spheroidal nodules in a ductile metallic matrix. The reduction or elimi for the production of ferritic ductile iron 14. Almost every foundry that uses batch type treatments to produce ductile iron adds a constant amount of magnesium to each ladle. When used in place of grey iron, the design of the casting is. Effect of magnesium and calcium as spheroidizers on the. Cast iron production when breaking out the casting the sand mould is destroyed, but of course new moulds can be made from the pattern using the same sand after it has been recycled. Pdf production of ductile iron using an indigenous 100kg rotary furnace was achieved using the ladle treatmentsandwich cover ladle method.
Austempered ductileiron castings advantages, production, properties and specifications abstract ductile irons, having a spheroidal or nodular graphite structure, are wellestablished engineering materials. They are commonly used for potable water distribution and the pumping of slurries, sewage and process chemicals. It is a comprehensive summary of data describing the engineering properties of ductile iron. Role of residual aluminium in ductile iron solidification. The title describes both the contents and the objective of this book.
Pig iron refers to the primary iron production of a blast furnace that contains over ninety percent iron. Research programs aimed at improving production technology, solving long standing production problems, and providing better manufacturing. Long radius and reducing elbows, reducing ontherun tees, side outlet fittings, eccentric reducers and laterals are ansi b16. Guidelines installation guide for ductile iron pipe. Introduction a large range of residual aluminium content in the iron melt for ductile iron production could be recorded, depending on the charge materials, such as pig iron, steel scrap, ferrosilicon, aluminium products incidence etc. Processing techniques and productions of ductile iron. Ecob customer services manager, elkem as, foundry products division abstract the objective of this paper is to provide an overview of some of the most common metallurgical defects found in the production of ductile cast iron today. Now available as a downloadable pdf file from the downloads page. Production of ductile iron using an indigenous 100kg rotary furnace was achieved using the ladle treatmentsandwich cover ladle method. The manufacture and process control of ascast ductile iron are discussed. Ductile cast iron frequently referred to as nodular or spheroid graphite iron is a recent member of the family of cast irons. Ductile iron pipe fittings production for water sewage. Method of producing ductile iron foseco international limited.
The article 16 shows the method of cheap ductile iron production on the base of steel scrap, while the authors of 17,18 presented the highsilicon cast iron and simo iron capabilities and. Back to awwa c11012 ductileiron and gray iron fittings pdf this standard describes 3 to 48in. About the ductile iron pipe research association dipra from its inception more than 100 years ago, the ductile iron pipe research association dipra has provided accurate, reliable, and essential engineering information about cast iron and now ductile iron pipe to a wide variety of utilities and consulting engineers. Difference between galvanized pipe and ductile cast iron.
Deteriorated graphite in casting surfaces summary dis research has shown that a considerable drop in the fatigue life of ductile iron castings occurs when there are surface defects or deteriorated graphite in the skin of castings. A ductile iron pipe is produced with centrifugal casting method. This article discusses the raw materials that are used for ductile iron production and outlines the most common and important requirements for. The present invention relates to a method for nodularizing treatment of ductile iron using a ladle treatment method for nodularizing of a magnesium ferrosilicon alloy, where a magnesium ferrosilicon nodularizing alloy consisting essentially of 40 to 80% by weight of silicon, 2 to 15% by weight of magnesium, 0. Production of ductile iron castings without feeders possibilities of producing ductile iron castings in green sand mould without feeders by means of ingate feeding and control of the graphite precipitation pattern by means of advanced thermal analysis. Oct 17, 2017 this is done to make iron more flexible and elastic. Pdf mechanical properties of sgiron with different. Recent development of ductile cast iron production technology. Cast iron flanges, like cast iron pipe, have a long and successful service history. It also requires less heating than malleable iron and so uses less energy. Ductile iron, also known as ductile cast iron, nodular cast iron, spheroidal graphite iron, spheroidal graphite cast iron and sg iron, is a type of graphiterich cast iron discovered in 1943 by keith millis.
Oluwasegun abstract ductile cast irons are materials having strength, impact toughness and ductility comparable to those of many grades of steel while exceeding by far those of standard gray irons. Dec 11, 1999 temperature where iron carbides fe3c are formed. Production of ductile iron castings1 cast iron science. Mechanical joint ductile iron pipe is addressed only through 24inch diameters in ansiawwa c151a21. Wo2004022791a1 method for production of ductile iron. As the production of sound castings without any defect is always the. Powdered ferrosilicon magnesium of 400g was used as a. Effect of basic chemical element in sgi ductile iron. Pdf processing techniques and productions of ductile iron. The first step of the production of ductile iron castings is the careful selection of the charge materials.
It is not intended to be a complete textbook or handbook on ductile iron. These considerations make it much cheaper for manufacturers to produce ductile iron than malleable iron. Mechanical joint pipe sizes 30inch through 48inch were eliminated from ansiawwa c151a21. Member companies ductile iron pipe research association. Ductile iron usually hypereutectic is produced by treatment with magnesium immediately prior to pouring castings see fig. The key difference between galvanized pipe and ductile cast iron is that galvanized pipes are produced by applying a zinc coating to cover the surface of pipes whereas ductile cast iron is produced by mixing graphite with iron. The youngest but most successful member of a truly ancient family, ductile iron has suffered from an abundance of myths and a lack. The main objective of the ductile iron society is to advance the technology, art, science of ductile iron production and to disseminate all such information to the members. Metal technologies currently has the capacity to produce 110,000 tons of ductile iron each year. The microstructure, properties and application of partial austenitization normalizing. Modern cored wire injection 2pe9 method in the production of ductile iron e. In the resin mould technique the sulphur in the ptoluol sulphonic acid ptsa, usually used as a hardener, has been identified as one factor causing graphite. Ductile iron, also known as ductile cast iron, nodular cast iron, spheroidal graphite iron, spheroidal graphite cast iron and sg iron, is a type of graphite rich cast iron discovered in 1943 by keith millis.