KASHAGAN PIPELINE REPLACEMENT PROJECT




Kazakhstan

ACTIVITIES

Construction
Pipeline

The project was executed in the northern territories of the Caspian Sea in the Republic of Kazakhstan.

The Kashagan Oil Field is located under the sea approximately 80 km southeast of the town of Atyrau. Field development includes production of crude oil and associated sour gas (>15% h2s) from the reservoir by a combination of offshore processing facilities and pipeline systems to transport the crude oil and gas to the onshore processing facility (opf), 40 km east of Atyrau. Here oil and gas are treated, conditioned and the transferred via existing infrastructures.

The overall pipeline system from the D-Island offshore facilities to the onshore processing facility comprises two 28” sour oil and gas pipelines 95.7 km long, running in a northerly direction with an offshore length of  65 km long from the top of the riser to the landfall location (shoreline) on the north coast of the Caspian Sea. The pipelines continue onshore to the processing facility in a pipeline with a total length of 30.7 km, including 4.1  km in a swamp.



The project presents several peculiarities:

 

  • In the winter, the air temperature drops to -30 °C and the climatic conditions are aggravated by a strong cold north-easterly wind, creating extreme blizzard conditions.
  • The water depth is very shallow in the area of development (ranging from a depth of approximately 4 m at Kashagan Oil Field to 0 m near the shore); there are seasonal and annual changes in the water level of the Caspian Sea, and the sea becomes ice-bound in winter.
  • The shallow water and swamp section crosses a special environmental region, referred to as a SER Zone, located between the progressives kp 52.3 and kp 67, with an overall length of 15 km. In this protected area, installation work is not allowed between 1 April and 15 July.

Scope of work

The scope of work includes the replacement of onshore oil and gas trunklines, the swamp section and shallow water sections. It also includes upgrading of the 5 onshore valve stations, with valve replacement.

The contract was awarded on 6th March 2015. Bonatti ensured the site was ready for operations before the project was officially awarded, performing preparation and early work, including logistical support, temporary construction facilities, winterisation plans, and personnel and equipment mobilisation. Bonatti immediately started trenching activities in shallow water in compliance with environmental restrictions.

Dredging of trench and flotation channel of trunklines in shallow water (SER Zone) was completed on 4th September 2015 VS 20th November 2015: 3 months ahead of schedule.

 

The welding requirements and acceptance criteria were ultra-demanding, with close to zero porosity, due to leakage which had occurred in the original installation.

Bonatti’s ROB.E 10:01 mechatronic welding system satisfied the demand for high quality. The system permitted simple transfer of know-how and technology to local welders following a brief training and induction period. Bonatti ROB.E 10:01 guarantees easy control of the welding process and satisfaction of the particularly demanding project requirements.

Project highlights

Human resources and safety performance

Total personnel

at peak

1,372 people
(including rotation)

total man-hours

worked

3,297,984

local workforce

employed

90%

lost time injury

frequency

0,06

Pipelaying

TOTAL LENGTH
INSTALLED
90.4 km
ONSHORE STRETCH
(laid with conventional method)
52.2 km
SWAMP STRETCH
(laid with push and pull method
- impraticable soil conditions)
8.2 km
SHALLOW WATER STRETCH
(laid with push and pull method)
30 km

Welding performance

PIPE MATERIAL
INSTALLED
API 5L X65 15.9 MM + CLAD INCONEL 625 3,0 MM
(iso grade cra clad cs pipeline 3183 L415)
OUR WELDING BEST PERFORMANCE
(joints per day
BNT ROB.E 10:01
automatic welding system)
30
TOTAL JOINTS
(executed with BNT ROB.E 10:01
automatic welding system)
1,288

Overall performance

DELIVERY
3 MONTHS
AHEAD
of schedule

CAREERS

Working at Bonatti means becoming part of dynamic team committed to achieving challenging objectives in international and multicultural contexts.

JOIN US FOLLOW US ON LINKEDIN

REQUEST INFORMATION

Contact us for any commercial and procurement request.

CONTACT US

BECOME A SUPPLIER

Quality, environment and safety starts with the procurement process.

FIND OUT MORE

We use cookies to ensure you get the best experience on our website. More information.