Welded steel structures

Process

Parameter

M. U.

Limits

Remarks

Min

Max

Stress release (primary heat treatment)

Overall sizes

mm

8000x5000x2800

Induction stress release

Overall sizes

mm

10.000x3500x3000

Vibration stress release

Press weight

Kg

   100             50.000

Automatic oxy-gas cutting as per dwg.

Thickness

Width

Length

mm

mm

mm

250

3000

12000

Plasma cutting of refractory and stainless steels

Thickness

Width

Length

mm

mm

mm

0,5

20

2500

12000

Mechanical cutting

Thickness and

Width

mm

15×3000

Plates or other items straightening

Plate thickness

mm

50

Welded structures redressing

Pressing force

Length

Width

Tf

mm

mm

250

3000

1600

Plates bending

Thickness

Width

mm

mm

1

1000

20

6000

Profiles bending

Profile height

Radius

mm

mm

10

500

100

Manual electric arc welding

Thickness

Thickness

Thickness

mm

mm

mm

1,5

2

2

100

20

20

Carbon steel, low alloyed and alloyed steel

Aluminium and aluminium alloys

Copper and copper alloys

Hardness tests

Hardness

HRC

30

60

Semiautomatic CO2 welding

Thickness

mm

2

300

Carbon steel or low alloyed steel

Electric arc Argon welding (W.I.G. method)

Thickness

Thickness

Thickness

mm

mm

mm

1

2

2

12

15

15

Carbon steel, low alloyed and alloyed steel

Aluminium and aluminium alloys

Copper and copper alloys

Submerged flux automatic welding

Thickness

mm

6

300

Carbon steel or low alloyed steel

Tack welding

Thickness

mm

0,5

3

APPROVALS FROM CERTIFICATION BODIES FOR EXECUTION OF WELDED STRUCTURES

  1. Approval for execution of welded structures as per DIN 18800-7 class E and DIN 15018. S.L.V. Munchen Institute
  2. Certification as per EN ISO 3834-2 S.L.V. Munchen Institute
  3. TUV SUD GRUPPE Institute (Germania) Certificate for execution of pressure equipment as per AD 2000 Merkblatt – Directive 97/23/EC
  4. Germanischer Lloyd Institute Certificate for execution of welded structures components in naval industry
  5. I.S.C.I.R Approval for repairing and mounting of lifting appliances
  6. I.S.C.I.R. Approval for repairing and mounting of pressure metallic vessels

 

Execution personnel:

– 27 certified welders as per EN 287 – 1 PROCESSES 111, 135, 136, 141.

 

Survey Personnel for welded structures execution:

– 1 EWE

–  1 welding engineer

 

Welding procedures qualified per welding processes:

– Welding with covered electrodes (111)

– Welding with solid wire MAG (135)

–  Welding with flux cored wire MAG ( 136 )

– MIG (131) welding

– WIG (141) welding

–  Submerged arc welding – UP (121)

 

Welding procedures for materials used in fabrication as per:

– EN 10025; EN 10028; EN 10083; EN 10088; EN 10137; EN 1563

 

Inspection of welded joints:

–  NDT testing ÷ RT; UT; MT; PT; metallographic analysis

–  Destructive testing ÷ tensile test, bend test, impact test, microhardness test – HV 10

 

Welding equipment:

–  Welding invertors with covered electrodes;

– MIG – MAG welding systems;

– WIG welding systems;

–  Submerged arc welding systems.

 

EXECUTION OF SHELL RINGS ON ROLLER

Plate thickness

( mm )

Shell ring length

( mm )

Diameter

( mm )

Remarks

1- 4

1500

150-1000

4-10

2600

400-6500

12-20

2600

800-6800

25-40

25-40

1500

2200

1500-6800

3000-6800

45-60

1600

1500-6800

With ends pre-heating and hot rolled

60-80

1200

3000-6800

With ends pre-heating and hot rolled

Note: Lengths greater than 2600 mm respectively 1600 mm can be executed from circular welded sections.