Offshore (OIH) exploration and development wells are drilled with the use of rigs. Rigs come in various sizes and with various characteristics.
Jack-ups are normally used for drilling in shallow waters. Floaters, which are used in deep water and ultra-deepwater drilling, include semisubmersibles and drillships.
In May 2017, Transocean (RIG) sold 15 high-specification jack-ups—ten existing jack-ups and five newbuilds under construction—to Borr Drilling. With this sale, Transocean is now a pure-play floater company. Recently, Transocean completed its acquisition of Songa Offshore. The combined company (Transocean and Songa Offshore) will operate a fleet of 51 offshore drilling units—30 ultra-deepwater floaters, 11 harsh-environment floaters, three deepwater floaters, and seven midwater floaters. Along with this, Transocean has four ultra-deepwater drillships under construction.
Seadrill Partners (SDLP) also doesn’t have a single jack-up in its fleet. The company operates semisubmersibles and drillships. Diamond Offshore Drilling (DO) also operates just one jack-up and all other floaters. The company operates a total of 19 rigs—14 semisubmersibles, four drillships, and one jack-up.
Ensco (ESV) recently acquired Atwood Oceanics. The combined company (Ensco and Atwood Oceanics) has the highest number of jack-ups among its peers. The combined company has 26 floaters and 37 jack-ups. Rowan Companies (RDC) has a fleet of 26 offshore drilling rigs, with 22 jack-up rigs and four ultra-deepwater drillships.