C-FER is one of a select few independent laboratories worldwide capable of executing test programs to these test protocols from CAL I for connections in relatively simple, low-consequence loading environments all the way to CAL IV for critical applications where gas-tight sealability of the connection is vital to well survival.
C-FER has the capability to perform and/or oversee all of the test program elements from material mapping and testing for test specimen test matrix generation all the way to limit load testing.
Make-Break Testing (Galling Resistance Testing and Test Specimen Assembly)
C-FER subcontracts Hallmark Technical Services to perform all of the vertically-oriented power makeups and torque monitoring for all make-break testing and specimen assemblies (including end cap buck-on); however, all make-break testing activities under a connection test program are performed in C-FER’s laboratory under the close supervision of C-FER’s connection testing experts.
All of the test specimen connection make-ups and break outs are performed vertically to be as representative of field conditions as possible.
C-FER has built dedicated specimen handling, cleaning, and inspection systems specifically designed for make-break testing to facilitate connection seal and thread inspection between make-ups.
URAP scanning can also be performed on connections after they are made up, and this is often done during multiple make-break rounds to track the changes in seal contact stress as a result of the repeated loading and unloading of the seal during this process.
C-FER has three permanent hydraulically actuated servo-controlled load frames capable of performing premium connection testing to any of the three aforementioned test protocols. Each of these frames has an axial load capacity of 3.5 million lbs (15 MN) in both tension and compression. All of the test frames are vertically oriented to allow for proper test specimen alignment and reduce the risk of gravity-induced sag effects that can result in test specimen buckling.
C-FER employs two methods to induce curvature in test specimens: four-point loading; in the Tubular Testing System (TTS) load frame for test specimens 9-5/8” (53.5 lb/ft P110) and smaller by reacting against the structure of the load frame, and high-capacity moment arms for tests involving specimens greater than 9-5/8” diameter (and 53.5 lb/ft P110) and tests occurring outside the TTS load frame.
High-Temperature Connection Testing
C-FER’s experience with high temperature premium connection testing started with premium connection testing for Cyclic Steam Stimulation (CSS) thermal operations in Alberta, Canada going back to 1990, and this testing has been a cornerstone to C-FER’s experimental testing services for the past 27 years.
C-FER has been contributing to the development and improvement of premium connection testing protocols for thermal applications, some of which laid the foundation for the Thermal Well Casing Connection Evaluation Protocol (TWCCEP), which has become an ISO Publicly Available Specification in ISO/PAS 12835 “Premium Connection Qualification for Thermal Applications.”
Technical experts from C-FER sit on the ISO/PAS 12835 technical committee in an effort to progress this protocol from a recommended specification to an international standard.
Performing thermal cycle testing in accordance with ISO/PAS 12835 is a very challenging endeavor that must be done right the first time.
Thermal cycle testing under this protocol subjects premium connections to extreme temperatures resulting in thermally-induced post-yield strain build-up in the test specimens from the very early stages of the thermal cycle process, and once specimens are plastically deformed, there’s no going back.
The unique combination of dedicated equipment, proprietary control and monitoring software, and unparalleled expertise in this area make C-FER the preferred choice of thermal well operators and OCTG connection manufacturers alike when it comes to thermal connection testing.
Complex Combined Loading
C-FER has performed several full-scale testing programs on OCTG connections requiring complex combined loading beyond ISO 13679/API RP 5C5 requirements.
As an example, C-FER has performed tests on OCTG requiring simultaneous external pressure, axial load, elevated temperature, and applied curvature with real-time strain monitoring at the connection.
Fit-for-purpose testing is often required in severe applications and C-FER has developed a strong reputation in industry for tackling very challenging applications through creative and thorough test engineering and meticulous test execution.