Common Failures In Onshore Oil & Gas Wells

Common Failures In Onshore Oil & Gas Wells

In the pursuit to further understand the challenges faced by oil and gas operators, Viking has maintained a failure database capable of determining common failures and failure trends. This information provides insight to aid in preventing common failures and improving industry practices to reduce incident rates in addition to saving time and money.

Failures Related to API 5CT High Strength Steels

American Petroleum Institute (API) 5CT high strength steels are extensively used for casing strings inwells subjected to high cyclic hydraulic fracturing loads. While non-sour grades of API steel such as P110 casing strings have been used satisfactorily for well construction, standard API P110 connections have seen higher rates of failures than pipe body failures in shale wells that require hydraulic fracturing.

Practical Guidelines for the Diagnosis and Remediation of Pipeline Blockages

One of the primary flow assurance challenges in the production of hydrocarbons is the prevention of pipeline blockages. Blockages can occur from a combination of improper system design, improper selection of piping and insulation materials, production chemistry aspects, inadequate or improper commissioning, startup and operating procedures, deviation from the proven operating procedures, changes in the operating conditions, intervention operations and improper maintenance procedures. The nature of the blockages can vary from "not-so-severe" to "hard-to-remediate" depending on the type of blockage.

Collapse Strength of Casing Subjected to Combined Load

Collapse Strength of Casing Subjected to Combined Load

Triaxial evaluation of wellbore loads is used extensively for casing and tubing string design and analysis. A triaxial based collapse strength method was recently adopted by the American Petroleum Institute (API), and an addendum issued to API Technical Report 5C3 (TR 5C3). The triaxial based collapse formula incorporates internal pressure and axial load into the calculation of casing and tubing collapse strengths.  Casing and tubing that are subjected to combined loads have higher collapse strength than previous formulas would predict, permitting the use of thinner walled, or lower strength, pipe than formerly required. 

Collapse Strength of Casing Subjected to Combined Load

Triaxial evaluation of loads is used extensively for casing and tubing string design and analysis. The paper presents a method of determining the triaxially based collapse strength of casing and tubing subjected to simultaneous axial and internal pressure loads. The triaxially based collapse strength method was recently adopted by the American Petroleum Institute (API) and an addendum issued to API Technical Report 5C3 (TR 5C3). Casing and tubing subjected to combined loads have higher collapse strength than previous formulas predict.

Advanced Technology Solutions for Next Generation HPHT Wells

This paper describes research efforts and technology development associated with the next generation of high pressure, high temperature (HPHT) well designs. Sometimes referred to as x-HPHT (extreme HPHT), work has been ongoing for several years looking at the next generation of HPHT wells for both subsea and shelf/onshore operations. A large number of challenges arise when addressing the engineering of HPHT wells.

Joining of Dissimilar Aluminum Alloys and Other Metals and Alloys by Friction-Stir Welding,

A wide range of aluminum alloys and other metals and alloys, particularly dissimilar materials, have been friction-stir welded in this study. These include Al 5052/Al 7075, Al 7075/Al 2017, Al 5052/Al 2017, Al 7×1×(Sc)/Al 7×5×(Sc), Cu/brass, and 6061 Al with a thin Cu sheet in the butted seam to observe particulate flow in the dynamically recrystallized regime which facilitates solid-state welding.