March 20, 2019 — In early April, Southwest Research Institute will open a new testing facility offering cost-efficient standard corrosion testing for oil and gas clients. The facility, located on the Institute’s San Antonio campus, will be used primarily to test the sulfide stress cracking (SSC) resistance of carbon steel alloys for oil wells and offshore drilling applications.
“Previously, our laboratory work has been predominantly fit-for-purpose testing,” said SwRI’s Dr. Elizabeth Trillo, one of the leaders of the project. “Those tests simulate an environment with specific solutions, temperatures and pressures to evaluate materials used in specific drilling environments and determine whether they can withstand those conditions. Every test is different, but our specialty is catering to the client’s end-use need.”
The goal of the facility is to provide cost effective standardized testing as a part of SwRI’s comprehensive oil and gas sour corrosion testing portfolio.
“Few industries operate under such harsh conditions,” Trillo said. “For this facility, we’ll mainly be looking at carbon steel materials used as casings in down-hole drilling applications with high hydrogen sulfide (H2S) levels.”
In drilling, the casing is a large pipe inserted into the Earth to protect the equipment and support the well stream. It’s usually held in place with cement and endures massive amounts of pressure, high temperatures and corrosive liquids. To withstand this environment, durable, lasting materials are necessary.
The National Association of Corrosion Engineers (NACE International) has developed particular tests and standards for materials used in the oil and gas industry. NACE standard test method TM0177 “Laboratory Testing of Metals for Resistance to Sulfide Stress Cracking and Stress Corrosion Cracking in H2S Environments” is widely used to qualify material performance in oilfield environments.
“We’ve typically designed new test methods that give us flexibility and control over individual environmental parameters,” said James Dante, manager of SwRI’s Environmental Performance of Materials Section. “This new facility will provide us with the ability to perform repetitive TMO177, NACE A testing in a cost effective and repeatable manner while providing our clients with same level of service they have experienced with more complex testing.”
SwRI is in the final stages of building its new laboratory, which is dedicated to the NACE A standard test method in TM0177. The facility will house multiple test cells allowing triplicate samples to be run on different materials. The proof ring cell assemblies are all housed within a customized glove box with nitrogen flow to ensure oxygen levels stay below 10 parts per billion.
“Previously, a sample would be grouped with several others and might fail early on in a 30-day test,” Senior Engineering Technologist Steve Clay said. “That could be challenging, because there was no way to initiate new tests without disturbing the other samples still under test. One of the benefits of this new facility is we’re able to test samples in isolated test cells giving us the ability to change samples without disturbing other samples still under test.”
As a matter of standard practice, the team will provide photographs of any cracks that occur during testing and will also report online environmental testing conditions including temperature and oxygen content.
Visit Southwest Research Institute at NACE’s CORROSION Conference & Expo 2019, Booth 945.
For more information, visit Sulfide Stress Cracking (SSC) Testing or contact Joanna Carver, (210) 522-2073, Communications Department, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238-5166.