Using Ductile Iron Pipe for Horizontal Directional Drilling Installations

Abstract

When the directional drilling method of pipeline installation was first introduced to the United States, members of the ductile iron pipe industry did not view their product as applicable to this method of installation. The reason; it was incorrectly believed that the directional drilling installation method required a pipe material with a uniform outside diameter throughout the entire pipe length. Consequently research and development efforts were put into action to design and test a ductile iron pipe restrained joint with a uniform outside diameter. In the meantime, the number of contractors and utilities installing Underground infrastructure by the directional drilling method has steadily increased. In the third annual Horizontal Directional Drilling survey conducted by Underground Construction magazine published in June 2001, it is reported that there are approximately 4,000 contractors and utilities engaged in Horizontal Directional Drilling construction. Of these contractors and utilities, 12.6% participate in the water market while 11% participate in the sewer market. A primary reason for this growth in the horizontal directional drilling method for the installation of underground utilities is expressed by Donovan Larson in a report presented at the AWWA 1997 Distribution System Symposium in Norfolk, Virginia. In a paper entitled, Using Directional Boring to Install Ductile Iron Pipe Larson states, This work of replacing main through open trenching techniques, which typically is located in older neighborhoods with established landscaping, driveways, and curbing is very disruptive. This statement is augmented in No-Dig Engineering , Volume 8, Number 2 in an article by Richard L. Stone, II, P. E., Project Engineer for Natural Gas Systems, Inc. located in Columbia, Missouri wherein is stated, Directional boring has proved to have less social and environmental impact for installing underground utilities.