SPE (Society of Petroleum Engineers)

A designated site containing multiple large storage tanks for oil, gas, or chemicals. Subcontractors frequently perform inspection, maintenance, and cleaning work at these facilities. Access permits and confined space certifications are typically required on site.

A belt conveyor mounted on a wheeled chassis that pivots in an arc to distribute bulk materials across a wide stockpile area. Subcontractors use them on aggregate, sand, and gravel sites to manage material placement without constant repositioning. They reduce manual labour and speed up site operations significantly.

A category of ongoing field service work covering routine inspections, preventive maintenance, and corrective repairs on infrastructure or equipment, often awarded to subcontractors through standing agreements or blanket contracts. For field service companies, IMR scopes provide a reliable stream of recurring work but typically require crews to mobilise quickly and hold multiple trade certifications to meet operator requirements.

The complete package of equipment, personnel, and services required to drill a well, which determines the scope of work subcontractors are hired into — whether supplying a single service line or multiple integrated components across the operation.

A real-time data acquisition process used during directional drilling that transmits downhole measurements — such as wellbore trajectory, formation data, and tool orientation — to surface crews without interrupting operations. For subcontractors, MWD services represent a specialised scope of work requiring certified technicians and dedicated equipment, often billed as a separate line item on drilling contracts.

A budgeting document used in oil and gas projects that outlines expected costs and seeks approval before work begins. Subcontractors often work under AFEs issued by operators.

What Is an AFE in Oil and Gas and How Does It Affect Subcontractor Payments?

An AFE (Authorization for Expenditure) controls every dollar spent on an oilfield project. Learn how it affects your billing, change orders, and cash flow as a subcontractor.