Threats to Onshore and Subsea Pipelines.
The data in these Tables are taken from References 1-4. Reference 4 defines ‘threat’ as: ‘an indication of an impending danger or harm to the system, which may have an adverse influence on the integrity of the system.’
| Threat Category | Threats listed in ASME B31.8S: 2014
(onshore pipelines carrying gas) |
Threats listed in API 1160: 2013
(pipelines carrying liquids) |
| Time dependent | External corrosion | External corrosion |
| Internal corrosion | Internal corrosion | |
| Selective seam corrosion (external or
internal) |
||
| Stress corrosion cracking | Stress corrosion cracking | |
| The growth of an initially non- injurious anomaly arising from any threat, leading to an injurious defect, via pressure-cycle-induced fatigue
(including transit fatigue) |
||
| Stable | Defective pipe seam | Defective pipe seam |
| Defective pipe | Defective pipe | |
| Defective pipe girth weld | Defective pipe girth weld | |
| Defective fabrication weld | Defective fabrication weld | |
| Wrinkle bend or buckle | Wrinkle bend or buckle | |
| Stripped threads/broken pipe/coupling | Stripped threads/broken
pipe/coupling |
|
| Gasket O-ring failure | Gasket O-ring failure | |
| Control/relief equipment malfunction | Control/relief equipment malfunction | |
| Seal/pump packing failure | Seal/pump packing failure | |
| Miscellaneous equipment failures | Miscellaneous equipment failures
(failure of valve or other component) |
|
| Time independent | Third-party/mechanical damage – damage inflicted by first, second, or third parties (instantaneous/immediate failure) | Third-party/mechanical damage – damage inflicted by first, second, or third parties instantaneous/immediate failure) |
| Third-party/mechanical damage –
previously damaged pipe (such as dents and/or gouges) (delayed failure mode) |
Third-party/mechanical damage –
previously damaged pipe (such as dents and/or gouges) (delayed failure mode) |
|
| Third-party/mechanical damage –
vandalism |
Third-party/mechanical damage –
vandalism |
|
| Incorrect operational procedure | Incorrect operational procedure | |
| Weather-related and outside force –
cold weather |
Weather-related and outside force –
cold weather |
|
| Weather-related and outside force –
lightning |
Weather-related and outside force –
lightning |
|
| Weather-related and outside force –
heavy rains or floods |
Weather-related and outside force-
heavy rains or floods |
|
| Weather-related and outside force –
earth movements |
Weather-related and outside force –
earth movements |
|
| Unknown | Unknown | Unknown |
| Interaction | Interaction of any of the above threats |
Table 1: Pipeline Threats from ASME [1] and API [2].
| Threat Category (from DNV RP F116 or PD 8010-4) | Threats listed in BSI PD 8010-4:2012
(pipelines on land and subsea) |
Threats listed in DNV RP F116: 2015
(subsea pipelines) |
| Corrosion/erosion | External corrosion – crevice corrosion | External corrosion |
| External corrosion – galvanic corrosion | ||
| External corrosion – soil corrosion | ||
| External corrosion – A.C. corrosion | ||
| External corrosion – D.C. stray current corrosion | ||
| External corrosion – atmospheric corrosion | ||
| External corrosion – corrosion under insulation | ||
| External corrosion – MIC | ||
| Internal corrosion – H2S corrosion | Internal corrosion | |
| Internal corrosion – MIC | ||
| Internal corrosion – CO2 corrosion | ||
| Internal corrosion – O2 corrosion | ||
| Internal corrosion – Erosion | Erosion | |
| Environmentally assisted cracking | Environmentally-induced cracking – hydrogen- induced | |
| Environmentally-induced cracking – stress
corrosion cracking |
||
| Third party threats/mechanical damage | Mechanical damage – third party impact | Traffic (vehicle impact, vibrations) |
| Trawling interference | ||
| Vessel impact | ||
| Anchoring | ||
| Mechanical damage – dropped objects | Dropped objects | |
| Mechanical damage – sabotage | Vandalism / terrorism | |
| Mechanical damage – unauthorized hot taps | ||
| Other mechanical impact | ||
| Structural | Global buckling (exposed) | |
| Global buckling (buried) | ||
| End expansion | ||
| On-bottom stability | ||
| Static overload | ||
| Natural hazard | Earthquakes | Earthquakes |
| Landslides | Landslides | |
| Extreme weather | ||
| Ice loads | ||
| Significant temperature
variations |
||
| Floods | ||
| Lightning | ||
| River crossing scour | ||
| Incorrect operational issues | Operational issues – incorrect operation | Incorrect procedures |
| Procedures not implemented | ||
| Human errors | ||
| Internal protection system related | ||
| Interface component related | ||
| Operational issues – blockage/freezing | ||
| Design/fabrication/ installation/ materials threats | Design and materials – pipe body defects | Design errors |
| Design and materials – seam weld defects | Fabrication related | |
| Construction – girth weld defects | Installation related | |
| Construction – damage e.g., dents, gouges | ||
| Equipment failure | Equipment failure – valve | |
| Equipment failure – flange | ||
| Equipment failure – pig launcher/receiver | ||
| Fatigue/structural | Pressure cycling | Fatigue (VIV, flow induced vibrations, waves, or process variations) |
| Thermal cycling | ||
| Cyclic external loading | ||
| Vortex-induced vibration (VIV) |
Table 2: Pipeline Threats from BSI [3] and DNV [4].
- Anon., ‘Managing System Integrity of Gas Pipelines’, ASME B31.8S-2014. American Society of Mechanical Engineers. New York, USA. 2014.
- Anon., ‘Managing System Integrity for Hazardous Liquid Pipelines’, American Petroleum Institute. API Recommended Practice 1160. Second Edition. September, 2013.
- Anon., ‘Pipeline systems Part 4: Steel pipelines on land and subsea pipelines – Code of practice for integrity management’, BSI PD 8010-4:2012. British Standards Institution. UK. 2012.
- Anon., ‘Integrity Management of Submarine Pipeline Systems’. Recommended Practice. DNV- RP-F116. Det Norske Veritas. Norway. October 2017.