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Lightweight stainless steel construction permits easy and simple lifting of pipe into place, 5 metres off the floor. (Top) Two men easily connect 6-metre lengths of pipe using relatively simple equipment. In addition, there is no need to clean the ends of the grooved pipe. Stainless steel sub-assemblies and pre-fabricated and curved, mitered sections avoid the need for complex fittings and connections. (Below) Smaller diameter copper pipes deliver water to various washrooms and concession stands. Stainless steel piping has been used in Detroit's Veterans Administration Hospital since 1993. Incoming potable water is pumped through 500-mm-diameter, schedule 10 pipe, made of S30403 stainless steel. The lines are insulated to prevent condensation.   |
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Nickel magazine, Jun. 01 -- It might take a few years, but stainless steel pipe could become as common in North American domestic water systems as it is currently in Japan or Germany. Penetration of stainless into the North American market is off to a good start with the completion of one such application at a high-profile venue in Detroit, Michigan.
The venue is a new, US$300-million stadium called Ford Field, which is being built by the Ford family, owners of the hometown "Lions" of the National Football League.
A total of 600 metres of S30403 stainless steel pipe -- 300 millimetres (mm) in diameter and with a wall thickness of 4.57 mm -- has been suspended from the concrete ceiling around the entire stadium perimeter. The grooved ends of the pipe were connected using mechanical couplings and smaller-diameter copper pipes deliver potable water from the main stainless pipe to various washrooms and concession stands around the stadium.
The pipe was manufactured by Felker Brothers and distributed by Bertsch, a USFlow Company.
W. J. O'Neil Company (WJO), a mechanical contractor, won a US$25-million contract to fabricate and install all the plumbing, waste and heating systems for the stadium, which is scheduled to open in time for the 2002 football season.
The decision to use stainless was based almost entirely on economics, according to Robert Gazda, General Manager of WJO. Although material costs were some 20% higher than if galvanized carbon steel pipe had been used, significant savings in fabrication and installation were realized as a result of opting for stainless.
The excellent corrosion resistance of stainless steel allowed thinner wall thicknesses to be used than other competitive materials, resulting in several factors that helped to reduce installation costs. Considerable weight savings per metre of pipe were realized, as well a greater ease in the handling, lifting and installation of long sections of pipe. WJO was able to install sections up to six metres long.
For the operators of the sports facility, the main advantage of stainless steel is that the lines need to be flushed only occasionally, whereas, if galvanized pipe had been used, more frequent flushing would have been required to remove the zinc corrosion products (zinc carbonate and sulphate) that inevitably develop. This means less labour will be required for flushing and less water will be wasted, an important consideration in a city where water supply costs have gone up by 30% in the past year.
Since stainless has never been used in a domestic water system in Michigan, no state engineering standard existed prior to this installation. It is not surprising, then that the City of Detroit put up some resistance. However, recent NiDI Water Workshop presentations in the region in the fall of 2000, and experience gained from the use of stainless steel cold water piping at the Veterans Hospital in Detroit, where 500-mm-diameter stainless steel pipe was installed in 1993 under Federal standards, helped convince city officials to accept the use of stainless steel at Ford Field.
Reflecting on WJO's success in developing an economical way to fabricate and install the stainless pipe, Gazda says, "I'm sure there will be a whole lot more jobs after this one."
Nickel Magazine, March 2008 -- The Japanese Stainless Steel Association (JSSA) has entered into a 3-year program designed to expand the use of long-lasting nickel-containing stainless steel in residential high-rise piping systems throughout the country.
The advantage of the all-stainless-steel piping system, as it’s called, is that the plumbing systems in high-rise buildings will last longer and require fewer repairs, thanks to the durability and corrosion-resistance of stainless steel.
With Dr. Kyosuke Sakaue, Professor of Meiji University as a leader of the JSSA team, both the Nickel Institute and the Japan Valve Manufacturers’ Association are participants in the government-subsidized project, which focuses on water supply and drainage pipes, as well as fire-fighting equipment, in collective housing.
JSSA proposed this program in response to a report tabled in May 2007 by the Housing and Land Investigation Committee of the then-governing Liberal Democratic Party of Japan.
According to the report, titled 200-Year Housing Vision, the average apartment building in Japan lasts only 30 years, compared with 55 years for American homes and 77 for English ones. The short lifespan is an economic burden for residents as well as a hindrance to conservation efforts.
The report urges the housing industry to adopt, as its goal, an average lifespan for all residential housing (including high-rise buildings) of 200 years. Future high-rises will be characterized by energy conservation, harmony with the surrounding environment, earthquake resistance, and regular and easy maintenance.
Most Japanese housing is multi-unit, consisting of both shared and private spaces. The report suggests that piping systems in shared areas be considered part of the whole “skeleton” of the residential structure. This concept calls for the installation of durable, stainless steel valves, reducing the need for repairs and expanding the life of the entire piping system.
Another advantage to longer-lasting housing will be a reduction in carbon dioxide emissions. Dismantling and rebuilding structures call for the production and transportation of pipes, valves and other materials, which in turn causes carbon dioxide emissions. The shift toward durable piping, and away from continuous replacement, will inevitably create a reduction in those emissions, as well as in overall energy consumption.
These and other benefits show how the country’s 200-Year Housing project is in keeping with the JSSA’s goal of developing demand for stainless steel products while contributing to environmental sustainability.
Earthquake-resistance tests have shown that stainless steel piping systems (joined by mechanical couplings) exhibit good air tightness and do not leak.
At a full-scale earthquake-testing facility, nicknamed “E-Defense,” the tests were jointly conducted by Japan Stainless Steel Association (JSSA), Building Research Institute, an Incorporated Administrative Agency, and National Research Institute for Earth Science and Disaster Prevention to evaluate the earthquake resistance performance of building materials and components.
The evaluation entailed building a 21-story “skeleton” high-rise. Between the first and fourth floors, a system was built to simulate earthquake shocks on floors 5 to 21. The power of the simulated shocks was based on the strength of earthquakes anticipated to occur in the Tokai and Tonankai regions of Japan.
JSSA is working on the technical development for super durable all stainless piping system, and this development includes a research on earthquake resistance tests for stainless steel piping system for 200-year housing. Accordingly the test results greatly help JSSA to promote a broad 3-year program for expanding the life of Japanese residential high-rises. (See the March issue.)
Nickel Magazine, March 2005 -- The piping systems that deliver potable water and fire-fighting capabilities in tall buildings have unique requirements. They must be able to withstand not only high pressures but the motion of the building caused by seismic and wind forces. Speed and ease of assembly are also important during the construction phase as builders grapple with tighter deadlines and a more fluid, less skilled workforce.
As buildings grow ever taller, engineers are turning to stainless steel piping systems ( S30400 and S31600) to meet these needs. Three of the newest and tallest buildings in the world, the Taipei Financial Centre in Taiwan, the Aurora tower in Brisbane, Australia and the Petronas Twin Towers in Kuala Lumpur, are prime examples of this shift to high-pressure stainless steel piping systems in certain circumstances.
Various controlled studies have served to give confidence in the use of stainless steel plumbing systems. Two examples are:
1) A 10 year Japanese study covering tubing trials in 2 large buildings, a hotel and a supermarket, examined lengths of type 304 stainless pipework in waters ranging from pH 7.1-8.8, 20mg/l chlorides, residual chlorine levels of 0.1-0.9mg/l and 28-50oC. Connections were made using welds, soldered fittings, stainless pressfittings, bronze compression fittings and flanged joints.
No corrosion was found on any of the pipes or their welds even under sediment. Pressfittings proved a very acceptable form of connection and showed no signs of crevice corrosion. Some general corrosion had taken place on the bronze fittings but this was slight and would not influence service performance. The study showed good performance from soldered joints although care has to be taken with soldering as problems occurred years ago in Europe when chloride based fluxes were used rather than phosphoric acid fluxes. Soldering has also been associated with knife-line type of attack and recommendations for suitable silver solders should be obtained from suppliers. If flanged joints are used, a polymeric gasket material suitable for use with stainless steel should be chosen
2) In Scotland, soft aggressive drinking waters have caused serious leakage problems in copper pipework. This was of particular concern in hospitals. To evaluate stainless steel as a replacement, parts of one hospital were retubed in 304 and 316 stainless steels and examined 2 years later. The water had a chloride content of about 20mg/l and pH of 8. The hot water pipe was 55-65oC. As a result, 316L was the alloy chosen for health care premises in Scotland. The initial trials used copper based compression fittings whereas stainless steel pressfittings have been used in subsequent installations. 10 years on, the performance of the early installations with pressfittings was assessed by the NHS in Scotland with samples of tubing removed and evaluated. The performance of the pressfittings was found to be excellent with no corrosion at all found in hot or cold water tubing.
