DRILLING TECHNOLOGY:
Heavy Weight Drill Pipe 

The need for a bottom hole assembly to prevent wall sticking that would be flexible enough to be used in directionally drilled holes was noted by a major oil company engineer at an API meeting in New Orleans, circa 1962. The company had tried using two pieces of concentric pipe with tar between the members. 

Called “flex weight”, this configuration could not withstand the environment in directional offshore wells. Glenn Chance, the local Drilco district manager, attended that API meeting. It occurred to him that welding tool joints on the ends of used drill collars might address the problem and, if successful, would significantly reduce drilling costs. For a second opinion, he consulted with Clifford Yancey of Rowan Drilling Co. in New Orleans, who agreed with the theory and two pieces were made. These proved to be too stiff. Drilco in Houston then turned the outside diameter on 30 used drill collars, leaving one wear pad 3-ft. long and welded 5-in. tool joints on each end. Unfortunately, the concept was not acceptable to operators until Albert Crownover, Tenneco’s drilling manager, agreed to run the pipe, which performed as expected. Drilco then modified 120 more collars, but the concept remained a tough sell to operators until J. B. N. Morris of Canal Rental, convinced Shell Oil Co. to test the idea and Bob Turnbull of Turnbull Rentals did the same. Ultimately, the concept became a standard for directional wells both on land and offshore, and was marketed under the name Hevi-Wate Drill Pipe. Since used drill collars soon became in short supply, Drilco engineer Sam Crews enlisted Timco Roller Bearings to produce a one piece, 27-ft. long, 5 ½-in.OD x 3-in. ID joint, with the specifications of Grade E drill pipe. Drilco built a machine which would fast turn the OD

of the joints, leaving a 3-ft. wear pad in the middle. In 1977, Glenn Chance organized Chance Collar Co.  By then, spiral drill collars had become a standard in directional drilling so Chance incorporated the spiral concept in his heavy weight product. Sales grew to some 3,500 pieces per month with a total value of a billion dollars annually and enabled worldwide development of offshore drilling.

Recognizing the pioneering efforts of the following individuals and companies that developed this technology:

Glenn G. Chance, Sam T. Crews and Drilco (now Smith International)