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SCAR RADIOGRAPHY SCAR and ‘Baby’ SCAR GAMMA RADIOGRAPHY

Who we are

Conventional and Advanced NDT and Inspection Services

Oil and Gas, Refinery, Petrochemical, Heavy Industry, Mining

Over 400 personnel including more than 300 inspectors

Thailand headquarters with International expertise since 1979

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SCAR

Small Controlled Area Radiography Two different SCAR systems 1. ‘Baby’ SCAR 989 Se 75, (Max 20 Curie) 2. SCAR 959M. 80 Ci of Se 75 or 15 Ci of Ir 192

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• Se-75 working range of 5-30mm steel thickness

• Ir 192 working range of 10-50mm steel thickness

• Se-75 has a softer gamma ray spectrum (66-401 keV)

than Iridium-192 (295-612 keV)

• Se 75 = Half Life of 119.8 days, (120 days)

• Ir 192 = Half Life of 73.83 days. (74 days)

Approx 46 days difference

SCAR

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Baby SCAR Projector

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SCAR Radiography

• Se75 is mid-thickness gamma radiography

• ‘Baby’ SCAR has a tungsten shield

• Weighs 7.5 kg

• ‘Encapsulated source’ NEVER leaves container

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Baby SCAR Projector

Baby SCAR container showing lock device and beam port.

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Octagonal Cross Section

Pellet shape improves Geometric Unsharpness therefore better quality radiograph

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Octagonal Cross Section

Diagonal of the octagonal pellet is 1.145 times pellet diameter. Diagonal of cylinder of the same diameter, is 1.414 times its diameter. The pellet geometry allows source to be up to 23.5% closer. This increases exposure rate per Curie at the object.

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Projector Placement

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Shielding Projector

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Survey Safe Distance

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Record Measurement of Safe Zone

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Reduced Area of Safe Zone From Football Pitch Size to Centre Circle Or Less

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Baby SCAR Radiography

Advantages of SCAR System

Safety Improvements - daylight working

No Downtime

Allows Continuous Construction Work

Schedules Maintained or Improved

On-line Radiography - Allows Instant Welder Performance Monitoring

‘Nucleonics’ Type instruments Not Affected

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SCAR Summary

• SCAR + Baby SCAR is safe to use 24 hours a day - no need for specific radiography windows.

• Cost efficient.

• The barriered area is always very small, plus collimation less than 10 m diameter (SCAR).

• Safe area is easier to see & control.

• SCAR will rarely affect other work.

• Equipment fits most pipe geometries.

• SCAR can replace most conventional radiography when planned in advance.

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How Can We Help?

Contact Email : info@dacon-inspection.com

Phone : +66 (0) 33 012 484-7

www.dacon-inspection.com