A Unique Project

TurkStream is a project that pushes industry boundaries from a technical perspective: TurkStream will be the first 32-inch sized system to be laid at depths of over 2 kilometers.

Designed for maximum safety

Each of the two offshore pipelines is made up of thousands of individual pipe joints of 12 meters in length. The pipes are produced in special mills and shipped to construction yards on the coats. The walls of the pipeline are made from 39 millimeters of high-quality carbon manganese steel so that it can withstand the huge pressure. Pipes laid closer to the shore are coated in concrete for added stability and protection against marine activities.

Pipelines are a safe, convenient and efficient way to transport natural gas from source to destination. When fully operational, TurkStream will offer a reliable energy supply for Turkey and the wider region by delivering 31.5 billion cubic meters of natural gas annually.

Pipes laid in shallow waters are coated with 5–8 centimeters of concrete for additional stability


Steel pipe
wall 3.9 сm

of three-layer

epoxy coating
against friction

Offshore pipe laying

Pipes are directly transported by ship to Pioneering Spirit, the largest construction vessel in the world. Onboard Pioneering Spirit, the pipe joints are welded onto the main string. Afterwards, the weld is tested and then coated, before the pipe string is lowered into the water. The pipe-laying vessel traverses the Black Sea adding new sections to the pipe string as it moves. Operating around the clock, Pioneering Spirit can lay over 3 kilometres of pipeline each day.

After production, the individual pipes are brought to storage yards on the Black Sea coast.

Production of plates



Ultrasound and x-ray

Special Coating

Shipment to the port

Shipment to the storage

Intermediate storage

Shipment to the vessel

Special vessel

Setting new standards

The technical and material specifications of TurkStream are setting new standards for the gas transport industry. The TurkStream Offshore Gas pipeline will be the largest system ever to be laid at depths as low as 2,200 metres. To ensure that the highest international standards are maintained from one end of the pipeline to the other, third party inspectors will be on hand during every stage of the Project to perform rigorous third-party checks.

Underwater filming

Using a Remotely Operated Vehicle (ROV), it is possible to film in the deep seas to investigate objects in detail and perform a visual inspection of the route. The ROV can also carry other instruments such as a sonar or a magnometer to ensure all relevant objects are found.

High-resolution seismic survey

A vessel produces a sonic source to make a large blast that hits the seabed and propagates under the surface. Surveyors analyse the return pulse to build up a sub-sea-soil acoustic image.

Echo sounding

A multi-beam echo sounder is used to emit a broad acoustic pulse, which bounces back onto the seabed in different ways to reveal the seabed profile. From here, a 3D model is formed which shows the depth of the water and shape of the seabed.

Sub-bottom profile survey

A transducer emits a sound pulse vertically towards the seafloor. A receiver records the return of the pulse. This technique helps create an image of the layers of sediment or rock under the seabed to determine if it is suitable for pipeline laying.

Side scan sonar survey

Used to create an image of large areas of the sea floor by scanning up to 500 metres left and right, to investigate any possible obstacles near the route.

Seabed samples

Using a range of different techniques, samples are taken from the seabed at different depths. The soil is then analyzed in a laboratory to determine if the seabed is suitable for the gas pipeline laying.

Maximum Depth, m
Offshore length, km
Franpipe in the North Sea, ø 110 cm
Nord Stream in the Baltic Sea, ø 122 cm
Langeled in the North Sea, ø 112 cm
Maghreb-Europe pipeline in the Mediterranean Sea, ø 56 cm
Trans-Mediaterranean Pipeline in the Mediaterranean Sea, ø 59 cm
Greenstream in the Mediterranean, ø 81 cm
Blue Stream in the Black Sea, ø 61 cm
Medgaz in the Mediterranean, ø 61 cm
TurkStream Offshore Pipeline in the Black Sea, ø 81 cm
Perdido Norte in the Gulf of Mexico, ø 46 cm

Exploring the Deep Seas

With the expertise of specialized engineers, TurkStream is applying advanced pipeline design and technology to create a pipeline that will safely withstand high pressure. The system has been divided across 2 separate gas pipelines, welded together from 12-metre pipe segments with a diameter of 81 centimetres each. Using the latest techniques in steel production and high-precision pipe manufacturing, engineers were able to design strong pipes with a wall thickness of 39mm. With over 150,000 pipes, the entire system will not only be strong enough to withstand the high external water pressure, but also resist an internal design pressure of 300 bar, thus enabling the safe and reliable transport of large volumes of natural gas.

With these unique design characteristics, TurkStream is a Project that will help lift the industry to a new standard in offshore gas transportation.

Inspecting the pipeline for safety and reliability

The pipe will be periodically inspected from the inside, by running pipeline inspection gauges, or PIGs, through it. The PIGs enter the pipeline at the Russian landfall facilities and are propelled by the gas flow towards the landfall facilities near Kiyikoy, where they are removed via special PIG receivers. Critical sections of the pipeline route, including slopes, trenches, anomalous seabed areas, and the continental shelf break, will be surveyed more frequently: first annually, and then as often as necessary based on monitoring results.

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Gazprom has been supplying natural gas to Turkey since as early as 1984.