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A global professional organisation that publishes technical standards, research, and best practices used across the oil and gas industry. Subcontractors may reference SPE papers and guidelines to meet operator technical requirements or bid on specialised work.

A timeline that outlines when specific tools, equipment, or crews are deployed downhole or on-site during an operation, dictating when a subcontractor's services are required and for how long. For field service companies, the run schedule directly determines mobilisation timing, crew rotations, and invoiceable hours on location.

The tracking, inspection, storage, and handling of oilfield pipe and casing on behalf of operators or drilling contractors. Subcontractors providing these services manage inventory, thread protection, and condition reporting at wellsite or yard facilities. Scope often includes running tally sheets, third-party inspections, and coordinating pipe delivery to rig floor.

A specialised subcontractor hired to perform a specific skilled trade, such as electrical, welding, or pipefitting. They are typically engaged by a general contractor rather than the project owner directly. Trade contractors are responsible for supplying their own tools, crew, and trade-specific certifications.

The process of installing pipe, casing, or tubing strings into a wellbore during drilling or completion operations. Subcontractors providing tubular running services supply specialised crews and equipment such as power tongs and elevators. Accurate job scoping is critical, as rig time is costly and delays directly affect invoicing and contract performance.

The prime contractor hired by an owner to manage a project, responsible for awarding and overseeing subcontracts. As a sub, your contract, invoicing, and site access typically flow through the GC. They control your payment terms and schedule, making them your primary business relationship on site.

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.