The Cincinnati Gas & Electric Company — Pipeline Safety Interpretation

Page 1PI-74-0154 December 17, 1974 Mr. Henry R. Meyers Manager, Engineering & Planning Gas Department The Cincinnati Gas & Electric Company Cincinnati, OH 45201 Dear Mr. Meyers: In your letter of November 18, 1974, you ask if the internal joint clamp you are considering for use in sealing a 24-inch cast-iron bell and spigot joint main would be considered as a mechanical leak clamp as required under 49 CFR 192.753(a). As described in the enclosure to your letter, this unit consists of a performed rubber boot that is designed to be installed on the inside of a circumferential joint and to seal against the prepared internal surfaces on each side of the joint. This boot is then locked in place by internal expansion rings. This would be considered as a mechanical leak clamp. Thank you for your interest in pipeline safety. Sincerely, Joseph C. Caldwell Director Office of Pipeline Safety#

Page 2November 18, 1974 Mr. Joseph C. Caldwell, Director Office of Pipeline Safety Department of Transportation Washington, D. C. 20590 Dear Mr. Caldwell: We are considering internal joint clamping of a 24-inch cast iron bell and spigot main using the Weco process. A brochure and article describing this process is enclosed. Please provide us with an interpretation of the acceptability of this method under 192.753(a) of the Minimum Safety Standards. In our opinion, the method is acceptable because metal bands press against the sealing strip on each side of the joint and fulfill the "mechanical clamp" requirement of the standard. Mr. Don Miller, President, Miller Pipeline Corporation, 210 S. Broadway, Green Springs, Ohio, has informed us that he will provide additional technical information on this process if you need it. The Miller Pipeline Corporation is licensed to install the Weco-Seal in the United States. Sincerely, THE CINCINNATI GAS & ELECTRIC COMPANY Henry R. Meyers Manager Engineering & Planning Gas Department NOTE: Article on "Transmission" attached with this letter.#