AWS D18.1:2009

This specification provides the requirements for welds in tubing systems in dairy and other food processing plants. The document addresses qualifications, fabrication, extent of visual examination, acceptance criteria, and documentation requirements.
Scope : This specification covers the requirements for Gas Tungsten Arc Welding and Plasma Arc Welding of stainless steels and nickel alloy tube and pipe 1/4 in [6 mm] diameter and larger in the fabrication and construction of new sanitary (hygienic) processing systems. This specification includes the welding of tube and pipe for the transportation of sanitary (hygienic) system products and cleaning or sanitizing solutions. It includes manual welding as well as automatic or mechanized welding, such as orbital welding. This specification addresses welding qualification and visual examination requirements for as-welded surfaces as well as finished surfaces This specification is intended for new construction. However, the requirements may also be applied to maintenance and repair of food processing equipment. When there is a conflict between this specification and a design specification to which the equipment is being constructed, the applicable code shall govern on issues that apply to structural design or structural integrity. This specification does not address requirements designed to prevent corrosion damage during service or any structural design or integrity aspects of components or systems used for sanitary (hygienic) applications. Sanitary processing systems are intended to include those systems handling products for human and animal consumption, or for cleaning and sanitizing solutions used in these systems. Such products include dairy, meat, poultry, vegetables, beverages, personal care items (such as shampoo, soap, toothpaste, cosmetics), and other products consumed or used by humans or animals, which require freedom from contamination. When this specification is stipulated in contract documents, conformance with all provisions of this specification are required, except for those provisions that the Owner, their representative, or contract documents specifically modifies or exempts. The Owner or their representatives shall provide a complete specification for the piping or tubing system. This specification makes use of both U.S. Customary Units and the International System of Units (SI). The latter are shown within brackets [ ] or in appropriate columns in tables or figures. The measurements may not be exact equivalents; therefore, each system must be used independently. Safety and health issues are beyond the scope of this standard, and therefore are not fully addressed herein. Safety and health information is available from other sources, including, but not limited to federal, state, and local regulations as well as other safety standards such as ANSI Z49.1, Safety in Welding, Cutting, and Allied Processes.