Answer:
Let’s start with “around a while”—The first solid expandable was installed 25 Nov 1999; thus, the technology is roughly 10 years old. In comparison to new technologies in other industries (computers, internet, software, cell phones, etc.), a 10-year-old technology is considered mature. However, in the oil industry, the average uptake for a new technology is approximately 17 years. Two recent examples of this acceptance period are logging while drilling (LWD) and rotary steerable system (RSS). So in comparison, expandables are just past the mid-point of industry-wide adoption.

Many of the risks associated with the deployment of expandables are due to hole environment. Hole preparation is critical to a successful expandable installation; yet this is where many people cut corners. With conventional casing, a “ram and cram” technique can get the string to setting depth. Using this technique with an expandable system is asking for trouble. If you damage the liner running in hole, you will not expand it pulling out of hole.

After nearly 1200 installations in a myriad of hole environments and applications, countless lessons learned have been applied to eliminate the risks encountered early on. Learning the operating envelope of each expandable system and understanding the hole environment (dogleg severity, depth, temperature, over whipstocks, junk, etc.) has - and is being used to produce sizeable gains in reliability.

Over the past four years, risk identification and mitigation response planning have also improved reliability. Many of the previous risks are totally eliminated by system enhancements and procedural re-design. Others have been addressed to reduce probability and/or impact of occurrence. Now, global expandable installation success is over 98% - all while pushing the operating limits of length, depth, angle, mud weight, and temperature.

Step-change improvement is usually a product of adversity. Adversity creates a greater sense of urgency and generates lessons learned. This is the evolutionary path Enventure has taken, and with our installation success ratio over the past four years, I doubt that expandables could be classified as “risky” today. Just as our customers profit from our experience, we also have profited immeasurably from our own experience.