Subsea systems should be monitored or inspected regularly, internally and externally. The inspection can provide such information as: geometry variation (dent, wrinkle, buckle, etc.), wall thickness variation (metal loss), corrosion, crack, leak, etc....

Crude oil is a complex mixture of hydrocarbons which consists of aromatics, paraffins, naphthenics, resins, asphaltenes, diamondoids, mercaptans, etc. When the temperature of crude oil is reduced, the heavy components of oil, like...

Flow assurance is required to determine the optimum flowline pipe size based on reservoir well fluid test results for the required flowrate and pressure. As the pipe size increases, the arrival pressure and...

Risers transport products from subsea wells, via flowlines, to topside facilities (import riser) or topside facilities, via pipelines, to onshore facilities (export riser). There are fixed static risers, free standing dynamic risers, or...

General Principle A pipeline can be a single or piggybacked pipeline system, pipe-in pipe or bundled system. Its expansion is dependent on the temperature, pressure profile, pipeline self weight and friction forces. The...

Rapid crack propagation, as its name implies, is a very fast fracture. Crack speeds up to 600 ft/sec have been measured. These fast cracks can also travel long distances, even hundreds of feet....

There’re several ways to construct a pipeline: Hot Rolling Cold Rolling Hot Tube Fiercing Welded Pipe Hot Rolling Hot rolling is a method to build semi-finished product of pipeline. The steel is formed...

A gooseneck (or goose neck) is a 180° pipe fitting at the top of a vertical pipe that prevents entry of water. Common implementations of goosenecks are ventilator piping or ducting for bathroom...

To keep the conveyed fluid warm, the pipeline should be heated by active or passive methods. The active heating methods include, electric heat tracing wires wrapped around the pipeline, circulating hot water through...

Pipelines installed on the seabed are subjected to hydrodynamic forces. Waves and steady currents that are characteristics of all offshore areas subject the pipeline on the seabed to drag, lift, and inertia forces....

Subsea tie-in is typically made by diver-assisted flange connectors for shallow water pipelines and diverless remotely operated vehicle (ROV) connectors for deepwater pipelines. There are three types of connectors available: flange, clamp (Graylok...

Before I tell you more about pipe-in-pipe, I’ll tell you one fact related with this topic which I just found last night during my research: The first known pipe-in-pipe system was installed in...

As I mentioned before, I’ll write about pig launcher/pig trap in one article very soon. I really meant it when I say “very soon”, you see.. In offshore pipeline, pigs generally need specially...

Pig is a device used for cleaning a pipeline or separating fluids being moved down the pipeline. It is inserted in the pipeline and carried along by pressurized flow of water, oil, or...

The hydrotests are conducted mainly to verify the mechanical strength of pipeline or pipeline sections. Hydrotesting is carried out by pressurizing the system to a specified internal pressure and holding it for a...

In order to prevent corrosion defects, over the past ten years there have been several manufacturing methods developed for producing Corrosion Resistant Alloy (CRA) clad/lined pipes. API (1993) has developed a specification for...

From the previous article in this blog, you may already know about pipeline material and grade selection. Now, in this post, I will write more about the difference and usage of high strength...