The sae standards, and draft standards, will be critically compared to those for astm and iso. 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. The unibell pvc pipe association at its annual conference aimed to separate the unproven theories over the years from the actual science. Specimens are to be prepared unnotched to dimensions in fig. Salient differences in the standards will be discussed and implications to design engineers will be addressed. View our product support area for downloads, installations and jointing procedures.
Ductile iron pipes and fittings bim object definition. For more specific values, follow the links immediately below. Impact properties of austempered spheroidal graphite cast. Ironpdf supports many customizations for generated pdf file formats including. Pipe is the recognized leader in highly engineered pipe products for water and wastewater systems. Ductile iron societyresearch committee report literature summary.
As an example of the higher test pressures this dictates, each length of 30 diameter ductile iron pipe, class 150 the lightest class produced, 0. The title describes both the contents and the objective of this book. While gray cast iron is relatively brittle by comparison with steel, ductile iron is not. The ductile iron used to manufacture the pipe is characterized by the spheroidal or nodular nature of the graphite within the iron, the pipe is manufactured using centrifugal. Ductile iron data for design engineers revised edition. It can have the highest tensile strength among the cast irons in the database. There is very little difference in machinability between this grade and 654512 and is rarely used because of the added cost of heattreating. 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. 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. Ductile iron pipe fitting and accessories, 151061 rev. Ductile iron pipe reference select mechanical or inflatable pipe plugs based on the below pipe id and along with the pressure to be blocked petersen does not sell pipe the following tables represent typical pipe inner diameters. In addition to the cost advantages offered by all castings, ductile iron, when compared to steel and malleable iron castings, also offers further cost savings.
Mechanical and structural properties of ductile cast iron. Grain boundary embrittlement and high temperature grain boundary instability are important factors in the quest for higher performance metals for many industrial applications. Flanged fittings are manufactured in accordance with ansiawwa c110a21. These and other standards are referenced throughout this section either by the full ansiawwa designation or by only the awwa numbering, such as awwa c110 or c153. Up to 95% of our product is made from recycled material.
The abrasion resistance of this new material is improved over that of adi and increases with increasing carbide content. Moreover, ductile iron is better than cast iron in difficult terrains. 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. In this study, we measured the impact characteristics of austempered ductile cast iron adi specimens by various external notches, and tried to clarify the effect of their induced microstructure on their impact characteristics. Mechanical properties dependency of the pearlite content. Before we discuss the practical uses for ductile iron also referred to as spheroidal or nodular iron lets talk about what it is and what makes it different what is ductile iron. Continuous testing and field experience have brought the production and use of ductile iron pipe to maturity. The youngest but most successful member of a truly ancient family, ductile iron has suffered from an abundance of myths and a lack. Ductile iron pipes and fittings are vital components of fire protection networks, with valves, pillar hydrants. The globalization and inoculation processes effectively improved the mechanical properties, particularly increased plasticity and toughness, which is higher than the strength of carbon steel. The influence of conditions of isothermal heat treatment on microstructure and mechanical properties of austempered ductile iron was searched on several sets of specimens which were different in temperature of isothermal transformation of austenite and holding time at this temperature. Work specified the work specified shall include all labor, material, equipment, tools, services and incidentals necessary to furnish and install ductile iron pipe, fittings and. Austempered ductile iron can be successfully produced from ductile iron castings with a wide range of chemical compositions and con.
Rendering pdf documents to images or thumbnails using ironpdf. Pdf articles ductile iron for heavy section wind mill castings. Ductile iron maintains the traditional qualities of cast irons, resulting from the high carbon content. Austempering ductile iron pdf austempered ductile iron castings, or adi castings are ductile iron castings processed by a special heat treatment. Invented in 1943, ductile iron is a group of irons that due to their microstructure, exhibit greater flexibility, strength and elasticity and are far more durable than other irons. This form of graphite favours the elasticity of the cast iron and increases its inherent strength. Carbidic austempered ductile iron cadi the new wear. This technical publication discusses the design basis and important criteria used in the wall thickness design of ductile iron pipe. The mechanical properties of ascast ductile iron strongly depend on the amount and distribution of ferrite in the microstructure. In fact ductile cast iron provides a wide spectrum of mechanical.
The austempering process results in friends of pdf. The questions and answers when it comes to understanding why ductileiron pipe fails, the di industry still struggles to come up with explanations and solutions. The pipe starts out as scrap metal from old cars and demolished buildings that is melted down and given a new lease on life. It is mostly different trace elements that do this. Processing techniques and productions of ductile iron. 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 importance of sic in the process of melting ductile iron with a. The subsurface defects where then visible in the animations. Ductile iron data a 200 page reference binder on designing and. Dipra has a technical publication to address virtually every aspect of the application of ductile iron pipe. Our tooling options include no bake and green sand molding. Jerry regula, national product engineer, mcwane ductile.
Introduction it is known that expansion of the ductile iron instytut. Ductile iron pipe guidelines technical publications dipra. Ductile iron society research committee report compiled by. This type of pipe is a direct development of earlier cast iron pipe, which it has superseded. Ductile iron pipe is hydrostatically tested to 75% of yield strength of the metal, based on the nominal thickness of the pipe. All pam pipes and fittings are manufactured from ductile iron complying with standards en 545 and iso 2531. An example use may be within a fire hydrant system. Application note segregation of impurities to interphase boundaries in ductile iron overview.
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. Visitors who tour a mcwane ductile facility are often surprised by how much work goes into making ductile iron pipe. As nzs 2280 ductile iron pressure pipes and fittings as4087 metallic flanges for waterworks purposes as4020 products in contact with drinking water coatings comply to the following standards. It is known that the ferrite content of the matrix depends on the chemical composition of the ductile iron and on the rate at which it is cooled through the. Cast iron gray iron white iron malleable iron blackheart malleable iron whiteheat malleable iron pearlitic malleable iron ductile iron compacted graphite iron. From the examination of these documents, it is concluded that the materials listed. A controlled amount of molten iron is introduced into the rotating mold, which generates a centrifugal force that holds. Difference between ductile iron and cast iron difference.
Current state of worldwide standards for ductile iron 200. The properties of austempered cast iron include eight common variations. The above three publications are available at no charge. Ductile iron is often used as a cost effective alternative to steel castings. Fracture surfaces of the austemered ductile without copper which austmpered at 2500c for a. A convenient pocketsize version of this guide is available. The point is, the graphite structures can be controlled. Ductile iron fittings shall be measured per each by the type and size, as indicated in the bid form. Carbidic austempered ductile iron cadi describes a family of ductile cast irons, with given amounts of carbides that are subsequently austempered to exhibit adequate toughness and excellent wear resistance. Pipe has supplied the critical components to ensure our nations water and sewer infrastructure is built to last.
In the paper an attempt to identify mechanism of shrinkage porosity formation in nodular iron castings during solidification was made. Annealed cast ductile iron can be bent, twisted or deformed without fracturing. The initial level was 40% and it decreased to 35% after sandblasting, indicating that the forces applied were sufficient to transform the bulk of the austenite present to martensite on the exposed surface. This is because they are much stronger than cast iron.
In the conducted melts, carbon and silicon deficiencies were. It is a comprehensive summary of data describing the engineering properties of ductile iron. The range can be used for potable water, raw water, watermains and sewer rising system applications. Ductile iron pipes and fittings comply fully with the requirements of the following standards. Ductile iron pipe is made from recycled ferric scrap, resulting in as high as 95% recycled content dipra member companies are committed to achieving targets the ensure the health and safety of employees and the public ductile iron pipe is designed to ensure 100 years of service life ductile iron pipe earned 69 points, including.
Ferritic ductile iron figure 1 presents the results of the investigation carried out by druschitz et al 8 on 654512 ferritic ductile iron tested at low strain rate 1% per minute at room temperature, in contact with various liquid environments. Ductile iron what ductile iron is ductile iron is a family of cast graphitic irons which possess high strength, ductility and resistance to shock. Materials a high purity pig iron was melt by high frequency induction furnace. Vinidex offers a range of ductile iron pipe systems that boast superior strength, high performance and unrivalled longevity. 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. Ductile iron improves the resistance to cracking which may occur in gray iron and ductile iron may be able to reduce overall dimensions and mass of a casting without sacrificing performance characteristics. Ductile iron is a kind of spherical graphite cast iron. Ductile iron also consists of nodular graphite, which gives it flexibility. With regard to practical uses, ductile iron pipes are used in sewer and water lines. Ductile iron pipes, fittings, accessories and their joints for water pipelines specification for coats on cement motor lined ductile iron pipes and fittings ductile iron pipes, fittings, accessories and their joints for sewerage pipelines ductile iron pipesexternal zinc. Payment shall include all labor, materials, tools and equipment for the completed installation and testing of the waterline, together with all incidentals nec essary to install the pipe and fittings co mplete. Ductile iron pipelines are described by characteristics such as jointing, external finish and internal finish. Its strength, toughness and ductility duplicate many grades of steel and far exceed those of standard gray irons.
Ductile iron is also called ductile cast iron, spheroidal graphite cast iron, or nodular cast. The austenite volume in the ausferrite was measured prior to and after blasting. Solidification and microstructure of thin walled ductile cast iron. Metalfit manufactures ductile iron and gray cast iron flanged fittings for both waterworks and industrial applications and conforms fully to the required industry standards. Ductile iron pipe is available in five pressure classes, defined as the rated working pressure of the pipe, based on a minimum yield strength of 42,000 psi and a 2.
Paper sizes, document output quality, content scaling, css media types and. The distinct, indisputable advantages to using ductile iron pipe instead of steel pipe have long been recognized by engineers, contractors, construction firm owners, and community leaders. It is a pipe made of ductile cast iron commonly used for potable water transmission and distribution. Austempered ductile iron adi, offers even greater mechanical properties and wear resistance, providing tensile strengths exceeding 230 ksi 1600 mpa. Extracting image and text content from pdf documents open a. Ductile iron pipe offers more durability, a higher degree of safety, an extremely. Fracture surfaces of the copper alloyed ductile iron which is austempered at 2500c for a 2hrs b 1. Ductile cast iron has good mechanical properties but it is necessary to re duce the wall.