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AWWA Flange Standards differ from ANSI (American National Standards Institute) and ASME (American Society of Mechanical Engineers) certifications in a variety of ways, the most important being their specificity: AWWA standards evaluate properties that particularly affect potable water use, as opposed to broader industrial flange applications. Our company provides an array of AWWA flanges to meet your application’s specifications.

What is AWWA?

AWWAThe American Water Works Association, formed in 1881, was developed to identify and unify major requirements for waterworks systems. Today, the international association serves non-profit, educational, and scientific roles to improve and support water quality and supply around the world.

Members of AWWA include water treatment plant management and operations teams, water utility organizations, manufacturers, scientists and environmentalists, regulators, academics, and researchers in the fields of water supply and public health. North America alone is home to 43 distinct AWWA Sections.

AWWA’s standards program began in 1908 with development and research to support regulatory standards for products, processes, and best practices. This invaluable reference is now recognized globally as a key source for scientific and management insight for water supply.

AWWA Standards

With over 150 Standards, AWWA supports a full range of water supply practices, equipment, and components. In addition to AWWA Flange Standards, waterworks specialists will find AWWA support covering:

  • Water treatment chemicals
  • Filtration materials
  • Meters and measures
  • Disinfection practices
  • Valves
  • Storage tanks of all sizes
  • Utility management practices
  • Pumps
  • Pipe and Fittings

AWWA Certified Flange Types

Unlike ANSI and ASME standards, AWWA Flange Standards do not address welded auxiliary connections or tapping. They cover a very specific range of flange types, including:

  • Slip-on Ring and Hub Type Flanges, fitted over a pipe
  • Blind Flanges, to seal or close a pipe or vessel
  • Threaded Iron Flanges, fitted to externally threaded pipes


Material Grades and Performance

The AWWA Standards program covers pipes, flanges, and fittings in all manner of materials, including:

  • Plastic
  • Ductile iron
  • Steel and stainless steel
  • Concrete
  • Asbestos-cement

AWWA C207 does not require a specific grade of steel, so long as the flange meets minimum standards for physical and chemical properties. These properties include:

  • .05% Sulfur (maximum)
  • .04% Phosphorus (maximum)
  • .29% Carbon (maximum)
  • 50,000 psi Tensile (minimum)
  • 32,000 psi Yield (minimum)

Industries and Applications

AWWA RINGThe waterworks-specific AWWA Standard Flanges have been developed to meet light duty applications, typically requiring performance at or below 300 psi. The most common pressure range is AWWA Class D, rated at 175 psi for sizes under 12 inches and 150 psi for larger sizes.

  • Common applications of AWWA Flanges include:
  • Waterworks
  • Slurry
  • Waste water
  • Plant piping

As a low pressure piping solution, AWWA Standard Flanges can be an effective cost saver over ANSI or ASME forged flanges. These flanges, designed for oil, steam, or chemical applications and their demand for high pressure, are typically more expensive and less necessary for low pressure piping.

For more information on using AWWA Standard flanges and fittings for your next project, or to find out more about custom and standardized flanges, reach out to the Coastal Flange team today.

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