Effective solutions for the safe and reliable delivery of large LNG Storage Tanks in the severe conditions of Northern Siberia

Patrick Genoud, Julien Castres Saint Martin, TOKYO, 05 APRIL 2017

1. Context

[Movie]

1. Innovative Design

2. Construction in Arctic conditions

3. Conclusion

OVERVIEW

We reject the idea that workplace

accidents are unavoidable.

Our management has a responsibility

to do its utmost to ensure the physical

integrity and the health of everyone

on our worksites and in the facilities

we operate.

We are committed to zero accident

objectives.

SAFETY : our SHARED VALUE towards zero accident

We strive for Zero accidents

Risk mitigation as early as design stages

Specific site trainings

Risk analysis of any taskSystematic prestart meeting

Management involvement

1- Context

MOVIE

The project best presented by those who build it

Arctic conditions

Lelu Island

(BC)

Melkøya Island

(hammerfest)

Sabetta

(Russia)

Sabetta : 71° 15' 25" North 72° 5' 46" East

Most extreme arctic conditions ever

Kenai(Alaska)

Useful previous experience

Hammerfest, NORWAY

Design, procurement and construction of :

- 2 full containment LNG tanks of 125,000m3capacity each. Post-tensioned Concreteouter containment and 9% Nickel steelinner tank.

- 1 full containment LPG tank of 45,000m3 capacity.

- 1 full containment condensate tank of 75,000m3 capacity.

Client : SNØHVIT Venture (Statoil, TOTAL, ENGIE, etc.)

Execution : 2002-2005

Dec. 2012 Call for tender

May 2013 Letter of intention & contract award 6 months = very short

Summer 2013 Mobilization at Sabetta

Winter 2013-2014 Start foundation works

Summer 2014 Concrete slab and wall slipforming for tanks T1 & T2 crucial summer windows

Summer 2015 Concrete slab and wall slipforming for tanks T3 & T4

Oct. 2016 Erection of modules for externals on tanks T1 & T2 critical works in winter also

Summer 2017 Erection of modules for externals on tanks T3 & T4

Mid 2017 Ready for cool down (RFCD) for tanks T1 & T2

End 2017 Ready for cool down (RFCD) for tanks T3 & T4

On Yamal LNG, an extremely tense timeline for preparation and execution

Scope of works

CLIENT JSC YAMAL LNG

Type of Contract Engineering, Procurement and Construction (EPC)

Type of LNG tank Above Ground, full containment

Number of tanks 4

Operating capacity 160,000m3 each

Inner tank 9% Nickel Steel

Outer tank Post-tensioned Concrete

Base slab type Elevated base slab

Foundation type Thermostabilized piledfoundation

2- Innovative Design

Pile design in Permafrost

948 steel/concrete 530mm dia. piles

948 pin bearings

Elevated slab

24m piles

1- Imposing deformations to a stiff structure results in high stresses

Pile design in PermafrostThe main issues

Concrete slab

Controlled Sand fill

UnstablePermafrost

Thermal deformations

Limited free height in winter

High shear force

High bending moment

“Siberian Sock” filled with flexible material

Longer free height in winter

Reduced shear

Reduced moment

Thermal deformations

2- Thawing may jeopardize permafrost stability

Thermostabilization of the permafrost

Pile design in PermafrostFast track implementation

Testing of flexible filling material under arctic conditions

“Sock” placing

Finished

Steel piles installed & filled with concrete

Number & length of piles reduced vs FEED base case

Simplified bearings (low seismic hazard)

Steel Sock on top of pile heads with special bitumen-based filling material in

annular space

Thermo-stabilization system on each pile (for stabilization of permafrost)

Optimization of foundation design in Permafrost

3- Construction in Arctic conditions

Mobilization

Maximization of external works during favorable weather window

Double shift (2 x 10 hours)

Rebars: cutting and bending in remote workshop / prefabrication on site

Slipforming (concrete wall)

Prefabrication of roof sectors

Assembly of roof sectors directly on top of the walls (full/concrete)

Modularization of external structures and piping

CONSTRUCTION CONSTRAINTS

PILE INSTALLATION

Piled foundations

Piled foundations

Slip-form for Wall concreting

Roof Sectors Fabrication & Transportation

Protection against harsh weather conditions

(for external works which cannot be performed within the favorable weather

window)

Mobile heated sheds (base slab concreting / roof sectors welding / external steel

tank plates welding)

Winterized batching plant / warehouse for concrete materials storage

Early supply of construction materials and equipment

Use of mobile cranes in lieu of tower cranes (severe blizzards)

CONSTRUCTION KEY ISSUES

Roof sectors installationwith central mast

Roof sectors installationwith central mast

Steel Roof in place

Concrete roof construction

Installation of electrical heaters

Two heaters by tank have been installed at temporary doors location;

With this system, temperature inside the tanks has been maintained at 5°C during

winter time and permitted to avoid any welding problems and to have good

working conditions.

CONSTRUCTION KEY ISSUES

Heaters inside the tank

Vapour barrier (steel liner) installation

Protected environment work (external envelope completion)

Hot air blowers

Automatic ultrasonic testing (AUT) for inner tank welds inspection → allows

welding on double shift basis.

Maximized use of automatic welding process (submerged arc welding- SAW and

Flux-cored arc welding - FCAW)

CONSTRUCTION KEY ISSUES

Erection of Thermal corner protection (TCP)

FABRICATION OF MODULES @ KALININGRAD

TRANSPORTATION OF MODULES

Installation of Modules on the Roof

Installation of Modules on the Roof

Installation of Modules (vertical pipe-rack)

Installation of Modules (vertical pipe-rack)

4- Conclusion

Anticipation

Complementarity

Communication

Control

The Fundamentals of Success

Thank you for your attention !