StressVision 2 Preview

7/23/2019 StressVision 2 Preview

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See the Unseen!!!

STAR.IK Ltd Canada

and

Navoi Mining and Metallurgical Complex Uzbekistan

Joint Research



StressVision-2 :

Mechanical Stresses Measurement



Introduction Able to detects and classifies the level of mechanical

stress in metallic structures and pressure equipment.

Mechanical stress may be present due to poor design,incorrect manufacturing techniques or the presence ofmanufacturing or in-service produced flaws.

The unique character of Stress Vision is not only indetecting serious flaws that are present in testcomponents but also in its ability to predict locations

where these types of flaws may initiate in the future.



cont…Introduction STRESSVISION also gives a severity classification for

these stress areas according to the concentration andgradients of these stresses. This allows fitness forpurpose judgments to be made on componentscontaining known flaws.



Why it is necessary? In 1901, British Navy ship (Cobra) had broken and sunk

even though it was built with great stress design andhigh safety precaution, 36 sailors dead

In 1903, investigation based on the similar vessel,British Navy destroyer (Wolf), shown that most likely

stresses from the tank started the incident



cont…Why it is necessary? Similar incident happen to a Tanker (Schenectady), it

has broken into two parts by spontaneous and visiblereasons

These kind ofincident also

happened to othertypes of constructions, eg;bridges, pipelines,

reservoirs, tanks…etc



Working Principle magnetic anisotropy of ferromagnetic materials

changes

a predictable and measurable manner when affectedby mechanical stress concentrators. Examples ofmechanical stress concentrators include geometric

section changes, introduced welding/manufacturingflaws, residual welding stress, in-service cracks andtears, residual plastic and thermoplastic stresses.



cont...Working Principle Unlike conventional ndt flaw-

detectors, STRESSVISION provides qualitative andquantitative information about the amount of damage(current or potential) created by the stress concentratorrather than accurate information about the size andshape of the concentrator.



cont...Working Principle A field of the π -shaped magnet in the

homogeneous unstressed material.



cont...Working Principle A field of the π -shaped magnet in the non-uniform

weighted material (on Stress).



cont...Working Principle estimate distortions of field of the π -shaped

magnetic field a fed of alternating current which is

perpendicular to the direction ofmagnetization

With the help of electrical signals on the

distortions of a starting signal of receptionspools, it is possible to estimate distortionsof the field of the π -shaped magnetic field



Typical Application Determination of heat treatment effectiveness

Detection and classification of welding flaws

Classification of known flaws for fitness

Detection and classification of in-service relatedmaterial degradation such as hydrogen embrittlement



ADVANTAGES Measurement of maximum shear stress

Compliance to the yield criterion of Tresca-Guest

Defining the stress concentration factor of

Absolute value of measured voltage

Detection of defects and assessment of their risk levels



cont…ADVANTAGES Mapping and visualization of the stresses in 2-D and 3-

D

Scanning of the measurement results

non-destructive procedure without surface preparation

Portable

Possibility of measuring the spot



CHARACTERISTICS mapping and visualization and definition of stress

concentration factor of stress in structures

components and parts of structures of ferromagneticmaterials;

No advance preparation of the surface;

Chance of measurements of submerged objects;employee Effect: properties magneto-anisotropicferromagnetic;



Basic Features minimum size of scanning area

: 90x90mm

number of measurement points

: 25 (minimum) to 14,434 (maximum)

number of scanning areas simultaneously

: 577, measuring time: 1 sec / point;



Specifications:

dimensions of the equipment: 224x227x147mm,

2.8kg weight,

assembly time of the equipment in the field: 30 sec.,

Accuracy of measuring the absolute voltage: 5%(charging),

20% (discharge); Food: autonomous (battery itself) with 8 hours of

operation;

High efficiency in stress measurement in steel alloy.

StressVision 2 Preview

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