Pretect

Corrosion Mapping Under Insulation (CUI)

Pulsed Eddy Current testing (PEC) is Eddy current test technique where pulses of low frequency eddy currents are used for inspection. Pulsed eddy current is basically a screening tool to detect the corrosion under insulation without removing them. Low frequency pulsed eddy currents are induced in the test material. The duration of sustained eddy currents in the test material is measured and a relative thickness or percentage remaining wall thickness is calculated for the average area of spot under the probe.

Application

• Corrosion survey & measuring the wall thickness over insulation.
• Applicable to Ferro–magnetic structures.
• Pipes, tanks, vessels and offshore installations.
• Can be done up to wall thickness 102 mm & Insulation thickness 305 mm (as mention in below chart)
  
  

Benefit

• Inspect through insulation, Technowrap, paints, concreate fire proofing & marine growth.
• Inspect through aluminium (1.0 mm), stainless steel (1.5 mm) and galvanized (0.5 mm) thickness weather jackets
• Measurement through heavy scale and corrosion without surface preparation.
• Sensitive to near side and far side defects.
• C–Scan image data recording in grid mapping and dynamic modes.
• No scaffold required – Rope access and Remote access capability.
• Can be done up to 120℃ surface temperature

Introduction

Phased Array is the ability to modify the characteristic of an acoustic probe by beam forming with help of software. This is done by time shifting the signal sent (pulse) and received (echo) to and from each element of a multi-element probe. Any UT technique for detection and sizing could be performed using Phased Array probes instead of conventional probe with great advantages.

Benefits

• PAUT is a well-established technique and recognized by many international codes (ASME, API, BSI, EN etc.) as a replacement to Radiography during construction activities.
• Inspection of difficult configurations.
• Indication height sizing helps for ECA analysis.
• Better signal to noise ratio.
• High probability of detection
• Data image can be presented in A-Scan, B-Scan (Side-view), C-Scan (Top-view), D-Scan (End-view) and S-Scan for better understanding and indication location and orientation.

Application

Weld Inspection from 0.84” and above.In-Service and Fabrication weld inspection of

• CS/LAS Material
• Corrosion-Resistant Alloy (CRA).
• Stainless steel.
• Dissimilar Welds & Clad Material