Oil and Gas Pipelines Industry Terminology

Anomaly

Any irregular indication from inspection or monitoring (e.g., corrosion, crack, dent, wrinkle, geotechnical movement, or leak) that may impair pipeline integrity and requires engineering assessment and possible remediation.

- “ILI identified a 40% wall-loss anomaly at MP 123.4 that requires a dig.” - “GIS shows a geohazard anomaly near the riverbank; we’re scheduling a patrol.” - “The caliper tool flagged a dent anomaly beneath the road crossing.”

API (American Petroleum Institute)

The U.S.-based standards organization publishing widely used pipeline and petroleum standards and recommended practices (e.g., API Spec 5L, API 1104 welding, RP 1160 integrity, RP 1130 CPM, RP 1173 PSMS).

- “Design must comply with API Spec 5L for line pipe.” - “Leak detection will follow API RP 1130 for CPM.” - “Our Integrity program aligns to API RP 1160 and safety management to API RP 1173.”

ASME B31.4

The code covering design, materials, construction, testing, and operation of liquid and slurry pipeline systems in the U.S.

- “Liquid line design is per ASME B31.4, including hydrotest factors.” - “Batching procedures must respect B31.4 requirements for overpressure protection.” - “Our design factor and wall thickness were set using ASME B31.4 tables.”

ASME B31.8

The code covering design, materials, construction, testing, and operation of gas transmission and distribution pipelines in the U.S.

- “The gas transmission project is designed to ASME B31.8.” - “Class location influences the B31.8 design factor and MAOP.” - “Repair methods were reviewed for B31.8 compliance.”

Batch (Batching)

Transporting different liquids sequentially in a single pipeline, separated by natural interfaces or pigs, with controls to manage mixing and quality.

- “We’ll run a diesel batch behind the gasoline with a small interface cut.” - “A batching pig will minimize mixing between products.” - “Tariffs specify minimum batch sizes and quality specs.”

Block Valve (Mainline Valve, MLV)

A valve installed on the mainline to isolate pipeline segments for operations, maintenance, or emergency response to minimize release consequences.

- “Install an MLV every 20 miles to limit spill volume.” - “The ESD will close upstream and downstream block valves.” - “The class change requires additional automated block valves.”

CAPEX (Capital Expenditure)

Upfront investment for assets like pipe, stations, storage, and controls required to build or expand a pipeline system.

- “The loop and new compressor add $450MM in CAPEX.” - “We’re optimizing CAPEX vs OPEX by using DRA instead of looping.” - “Lower CAPEX improves the project’s rate of return.”

Cathodic Protection (CP)

An electrochemical method to mitigate external corrosion by making the pipeline the cathode using impressed current or sacrificial anodes; verified via potential criteria and surveys.

- “Annual CP surveys found potentials below -850 mV; we’ll tune the rectifier.” - “Add distributed anodes near the river crossing.” - “Coating damage increased CP current demand.”

Class Location

A gas pipeline population-density designation (Class 1 to 4) used in B31.8 and DOT 192 to set design factors, MAOP, and certain safety requirements.

- “This segment is Class 3, so we reduced the design factor.” - “Population growth triggered a class location change assessment.” - “Class location affects MAOP and valve spacing.”

Coating (Pipeline Coating)

Protective layers (e.g., fusion-bonded epoxy, 3LPE/3LPP, tape wrap) applied to pipe to prevent external corrosion and reduce CP current demand.

- “The line uses FBE with 3LPE field joints.” - “Holiday detection found a defect near the bend.” - “Disbonded coating can accelerate external corrosion.”

Compressor Station

A facility that increases gas pressure to overcome frictional losses and maintain flow; includes compressors, scrubbers, cooling, controls, and safety systems.

- “We’ll add 30,000 HP to maintain throughput during winter.” - “The compressor trip caused a pressure transient.” - “Unit 2 suction scrubber needs maintenance.”

CPM (Computational Pipeline Monitoring)

Algorithm-based leak detection using real-time hydraulics, flow/pressure data, and models (e.g., mass balance, RTTM) to detect abnormal losses.

- “Our leak detection uses RTTM per API RP 1130.” - “New meters will improve CPM mass-balance accuracy.” - “We tuned CPM thresholds to reduce false alarms.”

Custody Transfer

The point and process where product ownership changes hands, requiring traceable measurement (metering, proving, sampling) and clear contractual terms.

- “The fiscal meter skid meets API MPMS accuracy.” - “We proved the meters before the custody transfer point.” - “Disputes were resolved with prover data.”

DOT 49 CFR Part 192

U.S. federal safety regulations for gas pipelines, covering design, construction, testing, operations, maintenance, and integrity management.

- “IMP for gas transmission is under 49 CFR 192 Subpart O.” - “Records must meet 192 traceable, verifiable, complete criteria.” - “MAOP reconfirmation applies per the Gas Mega Rule.”

DOT 49 CFR Part 195

U.S. federal safety regulations for hazardous liquid pipelines, covering design, construction, operations, maintenance, integrity management, and spill response.

- “Leak detection and CPM requirements are in 195.” - “HCA determination follows 195.450.” - “Hydrotest and repair criteria align with Part 195.”

DRA (Drag Reducing Agent)

Polymeric additives injected into liquid pipelines to reduce turbulent friction losses, enabling higher flow at the same pressure or lower energy at the same flow.

- “Inject 10–20 ppm DRA to hit the summer throughput target.” - “DRA reduces friction, lowering discharge pressure.” - “We’ll evaluate DRA vs looping on NPV.”

Emergency Response Plan (ERP)

Documented procedures, roles, contact trees, and resources for responding to incidents to protect people, the environment, and assets.

- “We’ll run a full-scale ERP drill with local responders.” - “Call-out and ICS roles are defined in the ERP.” - “The ERP includes worst-case discharge scenarios.”

ESD (Emergency Shutdown)

Automated or manual actions to rapidly place the system in a safe state (closing valves, tripping pumps/compressors, isolating sections) during emergencies.

- “An ESD trip will close MLVs and stop pumps.” - “Valve closure time is staged to manage surge.” - “Control room initiated ESD after the pressure alarm.”

Excavation Damage (Third-Party Damage)

External interference from digging or construction that strikes or weakens a pipeline; mitigated via one-call/811, locating, signage, patrols, and public awareness (API RP 1162).

- “811 notifications halved our hit rate.” - “We’ll patrol the ROW during the construction season.” - “Add line markers near the industrial park to deter encroachment.”

FERC (Federal Energy Regulatory Commission)

U.S. agency regulating interstate natural gas pipeline rates, services, and siting, and overseeing oil pipeline tariffs and rate indexation.

- “The interstate gas line needs a FERC Section 7(c) certificate.” - “Oil pipeline tariffs are filed with FERC and subject to indexing.” - “Negotiated rates require FERC acceptance.”

Gathering System

Upstream network that collects production from wells and delivers to processing plants or main transmission lines; typically lower pressure, shorter segments.

- “Low-pressure gathering feeds the gas plant.” - “Most gathering lines are state-regulated, not FERC-jurisdictional.” - “We’re consolidating gathering laterals to reduce OPEX.”

HCA (High Consequence Area)

Geographic areas where a pipeline failure could have significant consequences to people or the environment; triggers enhanced requirements under DOT Parts 192 and 195.

- “This segment impacts an HCA; integrity intervals are shorter.” - “HCA mapping supports our IMP risk analysis.” - “Valve spacing is reviewed for HCA mitigation.”

HDD (Horizontal Directional Drilling)

Trenchless construction method that drills a guided borehole for pulling the pipeline beneath obstacles like rivers, roads, and railways.

- “We’ll HDD under the river to avoid open-cut impacts.” - “Inadvertent returns were addressed in the crossing plan.” - “The bore profile limits curvature for pipe stress.”

Hydrostatic Test (Hydrotest)

Pressure testing with water to verify strength and tightness of a pipeline segment before service or after repairs, per code and regulatory criteria.

- “We’ll test at 1.25× MAOP for 8 hours plus a leak test.” - “Spike testing will screen for near-critical cracks.” - “Test records support MAOP establishment.”

ILI (In-Line Inspection)

Smart pigging with sensor-equipped tools (e.g., MFL, UT, EMAT, caliper) to assess wall loss, cracks, geometry, and other conditions without excavation.

- “MFL tool scheduled for metal-loss inspection next quarter.” - “UT crack tool will assess SCC colonies.” - “Caliper data showed an ovality anomaly at the bend.”

IMP (Integrity Management Program)

A risk-based framework required by regulation to identify threats, assess condition, prioritize repairs, and manage pipeline integrity throughout the asset life.

- “Our IMP integrates ILI, CP, and incident data for risk ranking.” - “HCA segments have defined assessment intervals.” - “Mitigations follow API RP 1160 methodology.”

Leak Detection

Technologies and practices (e.g., CPM, mass balance, pressure/flow alarms, fiber optics, aerial surveillance) to detect and locate leaks promptly.

- “We combine CPM with fiber-optic DAS for fast leak detection.” - “Aerial LiDAR flights supplement our patrols.” - “Set alarm thresholds to balance sensitivity vs false positives.”

Line Pack

The volume of gas stored within the pipeline under pressure; used to accommodate system balancing and transient demand swings.

- “We’ll use line pack to meet the morning gas demand peak.” - “Higher pressure increases available line pack.” - “Line pack changes will balance day-ahead nominations.”

Looping (Pipeline Loop)

Installing a parallel section of pipeline along an existing route to increase capacity or reduce hydraulic losses without replacing the original pipe.

- “A 20-mile 36-inch loop will debottleneck the corridor.” - “Looping reduces velocity and friction losses.” - “We compared looping vs compression on economics.”

MAOP (Maximum Allowable Operating Pressure)

The highest pressure at which a gas pipeline segment is allowed to operate, established by design, testing, and regulatory criteria (liquids use MOP terminology).

- “Records support MAOP verification per 192.” - “A class change may require MAOP reduction.” - “Hydrotest established MAOP for the new lateral; for liquids we reference MOP.”

Midstream

The sector between upstream production and downstream markets, including gathering, processing, transportation, storage, and related logistics.

- “Our midstream business includes gathering, processing, and pipelines.” - “Midstream M&A is active around key basins.” - “We’re expanding midstream takeaway to reduce flaring.”

MOC (Management of Change)

A formal process to evaluate and control risks when modifying equipment, procedures, software, or organizational elements, ensuring safe, documented changes.

- “All setpoint changes go through MOC per PSMS.” - “We initiated an MOC for the new pig launcher design.” - “Temporary bypass requires expedited MOC and risk review.”

NACE MR0175/ISO 15156

Materials standard for resistance to sulfide stress cracking and other H2S-related damage mechanisms in oil and gas environments (sour service).

- “Select CRA materials qualified per MR0175 for H2S service.” - “The sour gas requires limits on hardness to mitigate SSC.” - “We verified elastomer compatibility for sour conditions.”

Nominations (Shipper Nominations)

Shipper requests to schedule volumes at specified receipt and delivery points during defined cycles; the basis for daily pipeline scheduling.

- “Confirm day-ahead nominations by 10:30 central.” - “We’ll true-up intraday nominations after the compressor trip.” - “Counterparty confirmed receipts at the hub and deliveries at the citygate.”

Open Season

A marketing process where a pipeline solicits shipper commitments for new capacity or expansions, often leading to binding contracts and project sanction.

- “The non-binding open season will gauge market interest.” - “Anchor shippers executed precedent agreements post-open season.” - “Results support a 24-inch greenfield line.”

PHMSA (Pipeline and Hazardous Materials Safety Administration)

The U.S. federal agency (within DOT) that oversees pipeline safety rulemaking, compliance, enforcement, and incident reporting.

- “PHMSA issued a corrective action order after the incident.” - “The Gas Mega Rule expands PHMSA requirements for MAOP reconfirmation.” - “We submitted annual reports via the PHMSA portal.”

PIG (Smart Pig, Pipeline Inspection Gauge)

A device propelled through a pipeline to perform cleaning, separation, or inspection (smart pig) tasks, launched and received via dedicated traps.

- “Run a cleaning pig before the MFL tool.” - “The pig got stuck near the tight-radius bend.” - “Pigging frequency increased due to black powder.”

Pig Launcher/Receiver

Facilities (pig traps) that insert and retrieve pigs, equipped with closures, kicker/bypass lines, vents, drains, and instrumentation for safe pigging operations.

- “The launcher’s quick-opening closure needs maintenance.” - “Use the kicker line to start the pig.” - “We’ll vent and drain the receiver before opening.”

Pipeline Safety Management System (PSMS)

A structured management system for pipeline safety per API RP 1173, emphasizing leadership, risk management, operational controls, learning, and continuous improvement.

- “Our PSMS follows API RP 1173 with PDCA cycles.” - “Leadership and safety culture are central PSMS elements.” - “KPIs track PSMS effectiveness and continual improvement.”

Pressure Surge (Water Hammer)

A rapid transient pressure rise or drop due to sudden flow changes (e.g., valve closure, pump trip) that can exceed design limits without proper surge control.

- “Stage valve closures to mitigate surge per the model.” - “Install a surge relief valve downstream of the pump.” - “Pump trip caused a transient overpressure event.”

RBI (Risk-Based Inspection)

A methodology to prioritize inspection and maintenance by evaluating the probability and consequence of failure, focusing resources on highest risk items.

- “RBI ranked the river HCA dig sites as highest priority.” - “We adjusted inspection intervals based on RBI updates.” - “Data integration improved RBI consequencelikelihood estimates.”

Receipt Point and Delivery Point

Contract-defined interconnect locations where the pipeline receives product from shippers/suppliers (receipt) and delivers to customers/markets (delivery).

- “Increase receipts at Waha and deliveries to the citygate.” - “Tariff lists quality specs at receipt points.” - “Scheduling must balance all receipts and deliveries daily.”

Right-of-Way (ROW)

A corridor of land rights allowing installation, access, operation, and maintenance of the pipeline, subject to easements, permits, and landowner conditions.

- “We’ll mow the ROW and repair access roads this quarter.” - “An encroachment was found within the ROW setback.” - “ROW agreements define land rights and restrictions.”

SCC (Stress Corrosion Cracking)

Crack growth caused by the combined effect of tensile stress and a corrosive environment; includes high-pH and near-neutral pH forms in pipelines.

- “ILI EMAT data suggests near-neutral pH SCC.” - “Coating disbondment and tensile stress drive SCC risk.” - “Spike test was used to screen for critical SCC.”

SCADA (Supervisory Control and Data Acquisition)

Centralized system of field sensors, RTUs/PLCs, communications, and control interfaces used to monitor and operate pipelines and stations in real time.

- “SCADA polling shows stable suction pressure.” - “CRM procedures govern control room operations.” - “We upgraded radios and RTUs for better SCADA reliability.”

Shut-in

To cease flow by closing valves or stopping supply (wells, stations) for maintenance, safety, or market reasons; the line remains pressurized unless depressurized.

- “We’ll shut in the lateral until repairs are complete.” - “Storm surge triggered a precautionary shut-in.” - “Shut-in pressure trends help assess line pack.”

Tariff

Public document defining rates, terms and conditions of service, quality/pressure specs, receipt/delivery points, and nomination and payment rules.

- “The posted tariff sets transportation rates and quality specs.” - “We filed a tariff revision with FERC.” - “Shippers must meet tariff-requirement vapor pressure.”

Throughput

The volume of product transported over a period (e.g., bpd, MMscfd), used to assess capacity utilization, revenue, and system performance.

- “Average throughput was 520,000 bpd last quarter.” - “We’re at 92% capacity utilization.” - “DRA boosted throughput without new CAPEX.”

Tie-in

Connecting a new pipeline or facility segment to an existing system, performed as a planned shutdown (cold tie-in) or via hot tapping under pressure.

- “The shutdown window is for the cold tie-in weld.” - “We’ll hot-tap the header to avoid a full outage.” - “Tie-in stress analysis checks fit-up and loads.”

Water Crossing

Design and construction of pipeline segments across rivers, streams, or wetlands, accounting for scour, buoyancy, environmental protection, and permitting.

- “HDD is preferred for the wetland and river crossings.” - “Buoyancy control uses concrete coating and weights.” - “Permits include USACE Section 404 and state approvals.”