ADVANTAGES & ACTUAL LIMITS TO USE OF TMCP PLATESFOR LARGE STORAGE TANKSCONSTRUCTION

CMP DUNKERQUE PRESENTATION:

HEAVY FABRICATION PLANT IN NORTH OF FRANCE

ERECTED IN 1967 FOR FABRICATION OF HEAVY PRESSURE VESSELS FOR REFINERIES:CARBON & CHROMIUM MOLYBDENIUM STEELS UP TO 250 MM THICK

IN 1981 BOUGHT BY CBI FOR PREFABRICATION OF LARGE STORAGE TANKS & SPHERES:HLE STEELS & LOW TEMPERATURE CARBON STEELS

IN 1995 BOUGHT BY ENTREPOSE FOR PREFABRICATION OF CRYOGENIC TANKS & LARGE CRUDE OIL TANKS:9% NICKEL STEEL & HLE STEELS

ERECTION OF LARGE STORAGE TANKS

10 000 M3 SPHERES

125 000 M3 CRUDE OIL FRT

Beijing Natural Gas Project

ContractCFRFC-P98201

ENTREPOSE

DUNKERQUE

10 Spheres of 10 000 m3

Nanhuqu Site 4 spheres

Xiaotun Site 4 spheres

Beijiao Site 2 sphere

December 1998 - April 2001

Spheres Plates at Xingang Port

Spheres Plates stored at Nanhuqu Site

Internal scaffolding at Xiaotun Site

Erection of columns - Xiaotun Site

Erection of equatorial plates in progress - Xiaotun Site

Erection of equatorial plates completed - Xiaotun Site

Spheres before welding, erection completed - Xiaotun site

Four spheres under construction - Xiaotun site

Four spheres under construction

Nanhuqu site

Single Deck floating roof

Double Deck floating roof

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Erection of plates•The first step of construction is the erection, welding and NDT of bottom annular plates.

The erection of bottom plates and shell plates starts.

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Plates storage at site

•A suitable area is required in the near vicinity of the construction for storage of plates and other material.

•The plates are stored using wood wedges in order to guaranty the curvature.

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Plates Assembling•The square nuts are welded on the plates.•The plates are assembled with the key plates and the conical pins as shown here-under.

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Diameter and roundness control•Square nuts and conical pins are used to adjust the diameter of the first ring.

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Fabrication & installation of outer scaffolding

• The wind girder is used as scaffolding. Handrails are installed.

In order to provide free access to the workers, whatever is the design width of the girder, the actual width is at least 1m.

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Welding Technique• The vertical welds are welded from individual

cradles, by manual welding (coated electrodes). These cradles provide wind & rain protection for the

• welders.

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Welding Technique•The circular welds are welded simultaneously on both sides with an automatic welding machine (Arc Submerged•Welding). The machine turns automatically around the tank and carries two operators connected by radio, one on each side of the plate.

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Welding machine & cradle displacement

•When a vertical weld is completed the cradle rolls on the plate until the next weld.

• When a ring of plates is completed

the welding machine and cradles are

lifted on the above ring of

plates.FORWARD......BACKWARD HOME...

Tank Erection• Free access around the tank is required for

cranes and lifting operations.

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5 X 125 000 M3 FRT IN EQUADORERECTION IN PROGRESS

4 x 50 000 m3 DDFRT in GEORGIA

Erection completed!

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AT THIS STAGE I HOPE YOU UNDERSTAND HOWSITE CONDITIONS ARE DIFFERENT FROM LABORATORY!

WE AS CONSTRUCTION PEOPLES HAVE TO FACE ONSITE VERY BAD WEATHER CONDITIONS:

WATER FLOODING

WIND STORM

DEEP FREEZING

WE HAVE ALSO TO USE VERY LOW HEAT IMPUTWELDING PROCESS FOR ERECTION PURPOSE

AT THE END WE HAVE TO GUARANTEE CRACK FREEHUGE EQUIPMENTS WITH HOMOGENEOUS MECHANICALPROPERTIES THROUGH THICKNESS

CONSTRUCTION CODES& TMCP STEELS:

SPHERES

LARGE TANKS

PRESSURE VESSEL CODES AUTHORIZE USE OF TMCP STEELS WITHOUT LIMITATION FOR SPHERES

THEY REFER TO EN 10028 PART 5 OR EQUIVALENT

EN 10028 PART 5 DEFINE 3 GRADE OF STEELS:P355 / P420 / P460

FOR EACH GRADE THERE ARE 3 LEVELS OF TOUGHNESS = 27 JOULES AT T/4:

M FOR -20°C / ML1 FOR -40°C / ML2 FOR -50°C

MAXIMUM CEQ VALUES:T< 16MM P355 < 0.39 P420 < 0.43 P460 < 0.45T< 40MM P355 < 0.39 P420 < 0.45 P460 < 0.46T< 63MM P355 < 0.40 P420 < 0.46 P460 < 0.47

API 650 AUTHORIZE USE OF TMCP STEEL FOR LARGESTORAGE TANK

THE MAXIMUM GRADE AUTHORIZED IS 355

MAXIMUM THICKNESS AUTHORIZED 40 MM INSTEADOF 45MM FOR NORMALISED 355 GRADE

MAXIMUM GRADE AUTHORIZED IN Q&T STEEL 420

MAXIMUM THICKNESS IN Q&T STEEL 45 MM

NEVERTHELESS API 650 AUTHORIZE PURCHASER TO SPECIFY HIGHER VALUES UNDER HIS RESPONSABILITY

PROPERTIES OF TMCP VERSUS NORMALISED

FOR THE SAME GRADE TMCP HAS LOWER CHEMICALCONTENT ; FOR A 355 GRADE STEEL 40 MM THICK

TYPICAL ANALYSIS ARE AS FOLLOW:

CARBON : TMCP 0.10 / NORMALISED 0.14MANGANESE : TMCP 1.30 / NORMALISED 1.60NIOBIUM : TMCP 0.02 / NORMALISED 0.03CEQ : TMCP 0.37 / NORMALISED 0.42

DUE TO CONTROLLED ROLLING PROCESS THECHEMICAL ANALYSIS OF TMCP IS MUCH MOREHOMOGENEOUS THAN NORMALISED AND LEADTO DIMINUTION OF CARBON SEGREGATION AND

FURTHERMORE TO BETTER TOUGHNESS PROPERTIESMAINLY MID THICKNESS

WELDABILITY OF TMCP VERSUS NORMAISED

AS ALREADY FORESEEN CHEMICAL ANALYSISOF TMCP FOR THE SAME GRADE IS FAR LOWER THAN NORMALISED STEEL

IT MEANS PROBLEMS ON SITE ARE LESS WITH TMCP THAN WITH NORMALISED STEELS

IT MEANS ALSO WE CAN USE HIGHER GRADESOF TMCP I.E 420 WITH THE SAME WELDABILTYTHAN 355 NORMALISED GRADE AND INCREASETHE MAXIMUM SIZE OF LARGE STORAGE TANK

CONCLUSION

MAJOR STEEL MAKERS ARE TODAY USED TO PRODUCETMCP PLATES 50 MM THICK AND OVER ON A DAILY BASIS

CODES AUTHORISE USE OF THESE TMCP FOR LARGE SPHERES & STORAGE TANKS

WE HAVE TO CONVICE END USERS TO USE GRADE 420& OVER TO BE ABLE TO INCREASE MAXIMUM SIZESOF THESE LARGE TANKS IN A BETTER TECHNICO ECONOMICAL WAY THAN USING Q&T STEELS