Ductile iron pipe is pipe made of ductile cast iron commonly used for potable water transmission and distribution. This type of pipe is a direct development of earlier cast iron pipe, which it has superseded. The ductile iron used to manufacture the pipe is characterized by the spheroidal or nodular nature of the graphite within the iron. Typically, the pipe is manufactured using centrifugal casting in metal or resin lined moulds. Protective internal linings and external coatings are often applied to ductile iron pipes to inhibit corrosion: the standard internal lining is cement mortar and standard external coatings include bonded zinc, asphalt or water-based paint. In highly corrosive environments loose polyethylene sleeving (LPS) to encase the pipe may also be used. Life expectancy of unprotected ductile iron pipes depends on the corrosiveness of soil present and tends to be shorter where soil is highly corrosive However, a lifespan in excess of 100 years has been estimated for ductile iron pipelines installed using "evolved laying practices", including use of properly installed LPS (polyethylene encasement). Studies of ductile iron pipe's environmental impact have differing findings regarding emissions and energy consumed.
Ductile iron pipe manufactured in the United States has been certified as a sustainable product by the Institute for Market Transformation to Sustainability. Ductile iron pipe is sized according to a dimensionless term known as the Pipe Size or Nominal Diameter (known by its French abbreviation, DN). This is roughly equivalent to the pipe's internal diameter in inches or millimeters. However, it is the external diameter of the pipe that is kept constant between changes in wall thickness, in order to maintain compatibility in joints and fittings. Consequently, the internal diameter varies, sometimes significantly, from its nominal size. Nominal pipe sizes vary from 3 inches up to 64 inches, in increments of at least 1 inch, in the United States.
Pipe dimensions are standardised to the mutually incompatible AWWA C151 (U.S. Customary Units) in the United States, ISO 2531 / EN 545/598 (metric) in Europe, and AS/NZS 2280 (metric) in Australia and New Zealand. Although both metric, European and Australian are not compatible and pipes of identical nominal diameters have quite different dimensions.
Ductile iron pipes are available in a range of diameters from 80mm to 1600mm and are suitable for both potable water transmission, distribution and sewerage. Ductile iron pipes are simple to joint, can be laid in all weather conditions and often without the need for selected backfill. Its high safety factor and ability to accommodate ground movement make it the ideal pipeline material for a wide range of applications. Ductile's high degree of dependability is primarily due to its high strength, durability, and impact and corrosion resistance. Ductile Iron has minimum strength requirements of 60,000 psi tensile strength, 42,000 psi yield strength, and 10 percent minimum elongation. Designed and manufactured to the industry's most stringent standards, Ductile Iron Pipe resists damage during shipping and handling, and, once installed, withstands the most demanding operating conditions, including water hammer, frozen ground, deep trenches, areas of high water table and heavy traffic, river crossings, pipe on supports, rocky trenches, and areas of shifting, expansive, and unstable soils. Ductile iron pipe is a pipe made of ductile cast iron commonly used for potable water transmission and distribution. This type of pipe is a direct development of earlier cast iron pipe, which it has superseded. The ductile iron used to manufacture the pipe is characterized by the spheroidal or nodular nature of the graphite within the iron. Ductile Iron pipes are pipes made of ductile iron. They are commonly used for potable water distribution and the pumping of slurries, sewage and process chemicals. Ductile iron is a spheroidized graphite cast iron. Ductile iron pipes are a direct development of earlier cast iron pipes which it has now almost replaced. The high level of dependability on ductile iron pipes is due to its various superior properties and it is a most sought after pipe for many applications.
1 Inspection: Ductile Iron Pipe is normally shipped from foundries by rail or truck and, less frequently, by barge. It is rugged and will withstand the shocks and stresses normally encountered during transit. The purchaser may make arrangements with the manufacturer for inspection and acceptance of Ductile Iron Pipe and appurtenances at the manufacturer’s plant. When the pipe arrives at its destination, regardless of the method of transportation, it should be carefully inspected for damage that may have occurred in transit. Material found to be defective due to manufacture, or damaged during shipment should be recorded on the delivery receipt or similar document by the carrier’s agent. In addition, each shipment should be verified against shipping papers for any shortages or errors, which should also be recorded on the bill of lading or similar document by the carrier’s agent. The purchaser may make tests specified in the applicable AWWA standard to ensure compliance with the standard. The manufacturer or contractor is responsible for replacing defective materials.
2 Shipments: Most pipe shipped by DIPRA member companies is in the form of prepackaged bundles, which are placed as a unit on a truck or railcar. Depending on the number of tiers in a package, the bundles may be stacked two or more high. The pipe can also be loaded tier by tier. Loads on trucks or trailers are usually secured to the bed by nylon straps. Loads on railcars are almost universally fastened to the car with steel strapping. In making up tiers of pipe, whether for packages or direct loading on the transportation unit, every other pipe is normally turned so that, at each end of the tier, the pipe is alternately bell end to plain end. Adjacent pipes touch full length except for the short extension of the 10 bells beyond the plain ends. Bells on pipe of one tier should not touch or interfere with bells or barrels in the tier above or below.
3 Unloading: Pipe loads often have warning labels attached to the blocking with messages similar to the following: Important points of caution concerning the receiving and unloading of pipe are: 1. Trucks should be parked on level ground for unloading. 2. Before release of chains, cables, or strapping, an inspection should be made to ensure that chock blocks are securely in place on both ends of every support timber. Where chock blocks are missing or inadequately fastened, 11 corrections should be made. Under no circumstances should chocks be removed while there is any possibility of pipe rolling out of control and causing damage or injury. 3. Personnel should never remain on, in front of, or alongside a load of pipe after the restraints have been removed.
4 Slings: A variety of slings are available for handling pipe. Nylon slings, with an appropriate lifting capacity, are particularly well-suited for lifting Ductile Iron Pipe and appurtenances.
5 Hooks: Hooks used in the ends of pipe for unloading purposes should fit both the plain and bell ends without damaging or binding on the metal. The hooks are usually fabricated of one-inch or larger round bar stock, depending on the pipe size. Hooks should be padded, and care should be taken not to damage the interior lining and coating of the pipe, fittings, or valve and hydrant products.
6 Pipe Tongs: Several patented lifting tongs or clamp devices are available that release the pipe automatically when the hoist cable is slackened. Some clamps will fit the outside diameter of two or three different sizes of pipe, while other styles require a different clamp for each size of pipe being handled. Care should be taken when using pipe tongs near trenches that 14 have bracing protruding above the ground. If the pipe comes in contact with the bracing, the pipe tongs may release the pipe prematurely. During freezing weather, care should also be taken to ensure that the pipe-holding pads on the tong are kept ice-free to avoid pipe slippage, which could result in injury. All lifting devices should be inspected, repaired, and replaced on a timely basis.
7 Special Exterior Coatings: When pipe is furnished with special exterior coatings, handling devices such as slings, hooks, or tongs should be padded to prevent damage to the coatings. In addition, the coatings should be inspected for damage once the handling device is removed. For polyethylene encased pipe, damage should be repaired with polyethylene tape or by taping a section of polyethylene film over the damaged area.
8 Stacking: Pipe stored for an extended period of time should not be stacked higher than indicated in the following table. Timbers should be used to keep bottom tiers off the ground and to help keep dirt and debris out of the pipe. Pipe on succeeding tiers should be alternated bell end to plain end. At least two rows of timbers should be placed between tiers with chocks nailed at each end to prevent movement of the pipe. For safety and convenience, each size should be stacked separately
9 Fittings and Accessories: Fittings, valves, and fire hydrants should be drained and stored where they will not be damaged by freezing and should be handled in such a manner as to prevent damage. Small accessories, such as rubber gaskets, bolts, disinfecting chemicals, polyethylene encasement, and joint lubricants that are necessary for water main installation should be stored in a mobile tool house or supply shed until used. Lubricant for rubbergasketed joints is delivered in sealed containers and should be kept sanitary to make main disinfection easier.
10 Gaskets: Because gaskets supplied for typical water pipe projects using push-on or mechanical joints are made of synthetic rubber, Pipe Size (inches) 3 4 6 8 10 12 14 16 18 Pipe Size (inches) 20 24 30 36 42 48 54 60 64 Number of Tiers 18* 16* 13* 11* 10* 9* 8* 7 6 Number of Tiers 6 5 4 4 3 3 3 3 3 16 they should be stored in a cool location out of direct sunlight and should have no contact with petroleum products. Gaskets stored in this way will typically last for years in inventory and should be used on a first-in, first-out basis. Before use, gaskets should be checked for cracking or deterioration by looping the gasket in the manner done when a gasket is being installed. In cold weather, the gaskets should be warmed to facilitate installation. SBR (Styrene Butadiene) rubber gaskets are standard for normal service temperatures of up to 120oF for mechanical joints and 150oF for pushon joints. Special gaskets are available for higher temperatures and other special service requirements.
11 Delivery at Trench Site: To avoid unnecessary handling, the pipe and appurtenances should be placed as close as possible to the position they will occupy in the finished pipeline. The pipe is normally placed close to the trench on the side opposite the spoil bank. Pipe is normally strung along the trench with bells facing in the same direction. Pipe should be placed along the job site in locations to prevent runoff from rain events entering the pipe prior to use. It is helpful, where practical, to string pipes with ends (particularly bells) elevated off the ground to minimize cleaning required prior to installation.
Project Report on Ductile Iron Pipes Manufacturing includes Present Market Position and Expected Future Demand, Technology, Manufacturing Process, Investment Opportunity, Plant Economics and Project Financials. Report provides a comprehensive analysis from industry covering detailed reporting and evaluates the position of the industry by providing insights to the SWOT analysis of the industry. Each report include Plant Capacity, requirement of Land & Building, Plant & Machinery, Flow Sheet Diagram, Raw Materials detail with suppliers list, Total Capital Investment along with detailed calculation on Rate of Return, Break-Even Analysis and Profitability Analysis. The report also provides a birds eye view of the global industry with details on projected market size and then progresses to evaluate the industry in detail
1 The strong, safe, and reliable product has stood the test of time. Modern Ductile Iron Pipe is made to last over 100 years, and is an environmentally preferable product due to its recycled content, energy savings while in service, its durability, its own recyclability and because of the commitment of the Ductile Iron Pipe industry.
2 Ductile iron pipe is fabricated from recycled steel and ferric scrap metal.
3 Ductile iron pipe is made of up to 95 percent recycled content and is 100 percent recyclable material itself.
4 Years of usage have demonstrated no adverse health risks to the population.
5 Using ductile iron pipe saves up to 38 percent in energy consumption.
6 energy savings result in less carbon dioxide emissions.
7 Ductile iron pipe does not leach harmful chemicals into the public drinking water.
