Drillship

The upstream segment of the oil and gas industry covering the search for and extraction of hydrocarbons, representing the primary client base that hires field service subcontractors for drilling, completions, well servicing, and site construction work. Understanding whether a client operates in E&P helps subcontractors anticipate project cycles, budget timing, and the boom-and-bust demand patterns that directly affect contract volumes and payment schedules.

A structural anchor or connection point used to secure equipment, pipelines, or wellheads back to an existing infrastructure system, commonly referenced in subcontractor scopes of work when connecting new installations to live or existing lines. Subcontractors should confirm tieback specifications and isolation procedures clearly in their contracts, as this work often involves elevated risk and may require additional certifications or permits.

The segment of the oil and gas industry involved in exploration and production (E&P). Includes drilling, completions, and well operations.

Occupational Safety and Health Administration. The US federal agency responsible for workplace safety regulations. Compliance with OSHA standards is required for contractors working in the United States.

A ship-shaped offshore vessel that processes and stores crude oil or gas directly at sea, then transfers it to tankers — for subcontractors, FPSOs represent remote, long-duration worksites with strict offshore safety certification requirements, specialised crew rotation logistics, and scope that can span topside maintenance, marine systems, and instrumentation work simultaneously.

To create precisely spaced holes or openings in oil well casing and cement at a target formation depth, allowing hydrocarbons to flow into the wellbore; subcontractors providing perforating services typically work under wireline or coiled tubing crews and must coordinate closely with the operator's completion schedule.