Members of the AFS Copper Alloy Division provided a presentation on no-lead copper alloy casting for the recent American Water Works Association (AWWA) Annual Conference and Exposition (ACE16) on June 22 in Chicago. The Copper Alloy Division highlighted the various low-lead and no-lead alloys currently being used to make cast components for potable water systems. Components produced by metal casting are an integral part of the water works, both in the delivery systems as well as for in-residence components.
Traditionally, the copper-based alloys used in water work castings included lead as an alloying element. With the implementation of new legal regulations that limit the amount lead in material used for potable water, many non-leaded casting alloys have been developed and put into service to meet these new standards.
Many in the water industry continue to search for that “single safest no-lead alloy” to fit all needs.
AFS believes no single alloy will be able to make the variety of casting sizes and geometries needed for plumbing use, and multiple alloy alternatives are necessary to meet the full range of cast components required for water applications.
In the presentation at the AWWA ACE16 convention, the members of the AFS Copper Alloy Division discussed the different no-lead alloys that meet the new laws and are currently being cast into plumbing products. Copper alloy metal castings are a major part of water distribution for industry and home-owners in four primary areas: hydrants, water delivery system (the water main to the in-house meter), water meters, and in-home plumbing components (water meter to faucet).
More than 30 copper alloys are listed in the ASTM standards as containing a maximum of 0.1% lead, and several more are listed that contain a maximum of 0.25% lead, the limit set in the new regulations. In addition, new alloys continue to be developed and enter the marketplace. The AFS presentation discussed the various alloys in detail, comparing their mechanical properties and castability, and provided foundry practices for each alloy.
The AFS members emphasized that, rather than a single alloy solution for the entire industry, a multitude of metallurgical choices are available, all of which meet current government regulations and can be tailored to specific component applications.
Headquartered in Schaumburg, Ill., AFS is a not-for-profit technical and management society that has existed since 1896 to provide and promote knowledge and services that strengthen the metalcasting industry for the ultimate benefit of its customers and society.