R&D efforts pursued for HPHT deepwater drilling conditions

The next generation of High-Pressure, High-Temperature (HPHT) well designs forges ahead with advancements in material testing, heavy load handling and technology.

Mike Payne and David Pattillo, BP America; Richard Miller and Carl Johnson, Viking Engineering LLC

HPHT deepwater drilling is an environmentally demanding, costly endeavor, and meeting the challenges in well design and planning has required intense research efforts and technology development. Despite the challenges of Extreme HPHT (xHPHT), reserve forecasts accompanying deep horizons remain high. Therefore, BP, along with industry partners, continues to progress in key well design and drilling technologies including material testing and qualification, heavy load handling and HT electronics.

HPHT WELL CLASSIFICATIONS

Classifications outline differentiations among HPHT well classes. Deep wells in deepwater operating areas currently involve HPHT and Ultra HPHT well classes. Figure 1 shows one classification scheme for HPHT wells.

In this case, HPHT wells exhibit bottomhole pressures above 10,000 psi (10 ksi) and temperatures above 150°C. This HPHT classification includes wells up to 15 ksi and 175°C as shown. Ultra HPHT wells, the next class, involve pressures up to 20 ksi and 200°C. The final class, xHPHT, of wells have pressures up to 30 ksi and temperatures up to 260°C and involve only deep gas plays on the shelf and in onshore operating areas.

Within the 15-ksi ratings, significant pieces of equipment lack full-field history in operating conditions up to 15 ksi. Well design and planning demands attention to detail and in-depth technology studies.