Advanced Technologies and Practical Solutions for Challenging Drilling Applications

Abstract

This paper provides a review of recent technology advancements and addresses practical considerations associated with drillpipe and drill stem components for extreme drilling applications. Ultra-high torque double-shoulder rotary connections are often employed in these applications. Recent developments and enchantments in these connection designs including new higher strength materials, advanced thread forms and associated improvements in torsional strength and fatigue performance are presented. Deepwater wells frequently require long, heavy casing strings to achieve the total depth objectives. High capacity landing strings capable of running these heavy strings with total hook loads approaching 2.5 million pounds have been successfully developed to address this well design challenge. The paper discusses the engineering solutions implemented to overcome the high forces, slip crushing concerns and material strength and toughness considerations for these critical applications. Due to the dramatic increase in oil prices the industry has seen a re-emergence of deep and ultra-deep drilling projects that encounter H2S gas. The paper provides an update on the latest sulphide stress cracking (SSC) resistant drillpipe grades including the first fully SSC resistant drill pipe system with SSC resistant friction welds joining the drill pipe tubes and tool joints. Major operators have been using a drill pipe based riser system for intervention and completion work in the waters offshore Brazil, Australia, Africa and other deepwater basins around the world. The paper provides updates on design improvements of high pressure capacity connectors and advanced materials for these critical riser applications. Deepwater and other critical wells often encounter abrasive formations, high side loads between the drill string and bore hole and other conditions that promote drill stem friction heating failures. The paper includes characteristic features of these failures along with case histories and prevention methods.

Load Calculation and Strength Analysis of the Deepwater Landing Drill Pipe-Lowering Operation

“…In addition, some scholars, taking into account the characteristics of deepwater environmental loads and the operational conditions of unsegregated water pipes, have developed a design approach primarily based on axial static loads. This approach focuses on the static strength design and dynamic verification of the deepwater unsegregated water pipe descent riser, leading to the acquisition of certain regular insights [16][17][18][19][20].…”

Loads Calculation and Strength Calculation of Landing String during Deepwater Drilling

“…In 2012, Gao Deli et al [16] elaborated the longi and transverse bending deformation mechanical model and longitudinal vibration of the landing string, analyzed the factors affecting the deformation of the string variation law, and proposed the strength design and calibration method of the string. In 2014, Jellison et al [17] proposed a series of engineering measures to i the load-bearing capacity of the landing string from the perspective of production in view of the current engineering situation where the existing landing string n bear huge tensile loads. In 2016, Plessis et al [18] proposed a structure capable of a more than 2,500,000-lbf deepwater drilling landing string and presented a s related support technologies to guide drilling engineers in the design of dee solutions [19].…”