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A number of states, including all the New England states, require that any pressure vessel installed within their jurisdiction be certified by the
American Society of Mechanical Engineers (A.S.M.E.). The following explains the significance of this certification.

Dillon Boiler Services Co., Inc. holds A.S.M.E. "A", "S", "U", "PP" and "H" Stamps covering the fabrication and alteration of
high pressure boilers, unfired pressure vessels, power piping and heating boilers. We have the National Board "R" Stamp No. 182,
allowing the repair of all boilers and pressure vessels.

Requirements for code stamp qualification include certification of each welder, documentation of material and acceptance of the finished
product by the Quality Control Manager and Authorized Inspector. Products manufactured and accepted by an A.S.M.E. inspector bear the
appropriate symbol stamped on a nameplate affixed to each vessel.

Welders must be certified under the supervision of the Shop Foreman and Welding Engineer for each welding process and
position within a material classification and thickness range.

All material used in code manufacture must be documented. A mill test report bearing the heat number and material specification, describing
the chemical analysis and physical properties of the steel, must be stenciled by the mill on each steel sheet.

All A.S.M.E. manufacturers have an Authorized Inspector, who is the judge of code acceptability. He is an employee of a licensed insurance
company and has jurisdiction over all code phases of manufacture. He is authorized to suspend manufacture at any time or request
that code imperfections be corrected.

The Inspector and the Quality Control Manager actually travel with each project through all phases of the work. After the parts fit-up, they check for
alignment and insure that a difference not-to-exceed one-fourth of the material thickness is present. The quality of weld is then checked. Outside
visual inspection checks for pinholes, undercuts, overlap, lack of weld penetration, slag inclusion and excessive reinforcement. When appropriate,
X-ray or other non-destructive examination is used. At the final inspection, the units are hydrostatically tested at 1.5 times working pressure
and are observed for leaks.

Upon completion of the vessels, a Manufacturer's Data Report, Form U-1A is completed. The original copy is filed with the
National Board of Boiler and Pressure Vessel Inspectors in Columbus, Ohio, a copy is retained at Dillon and a copy is provided to the customer.

Home Page - About Dillon - Location

380 Crawford St., Fitchburg, MA 01420-6898
Tel: (978) 345-4351 FAX: (978) 345-1646