Monday, October 04, 2010

TCR Advanced completes Eddy Current Project for Essar in India

IMG00004 IMG00005 IMG00006 IMG00007 IMG00008

TCR Advanced carried out  Eddy Current Testing services for Essar Power (India) ltd., Salaya project – Jamnagar. Eddy Current Testing (ECT) is an electromagnetic NDT technique widely used in Power Plants (Nuclear, Thermal, Gas Turbine), Petrochemical, Refineries and other Industries where tubular Heat Exchangers, Coolers, Condensers are provided. 

The assignment at EPIL – Jamnagar was testing of condenser tubes 0.5mm and 0.7mm thick x 25mm OD x 11820mm long. MOC of the same is Titanium. The inspection was pre-service inspection and was intended to find out surface / subsurface defects on OD & ID.

The above test is not a volumetric technique.  This is a surface technique and can readily detect very shallow surface defects (fatigue crack, inter-granular stress corrosion cracks etc), sub surface defects (inclusions, voids etc.) within a depth of say 6 mm.  It can also identify pitting, cracking, microbiological induced corrosion damage, support wear, erosion etc.  and hence is very widely used as an important tool of in-service inspection of heat exchangers.

This Non destructive testing using a multi frequency Eddy Current system would examine surface and sub-surface areas of materials with suitable electrical conductive and magnetic properties. The instrument used allows Inspection of a large variety of materials and provides documentation of the inspection all in one unit. 

Features of testing machine

Ø Capable of Multi Frequency Testing.

Ø Capable of performing multi channel (4 channels) data acquisition in differential as well as absolute mode.

Ø Phase angle rotation for signal is adjustable from 0 to 360 degrees with angle increments of minimum 1 degree.

Ø Signal amplitude magnification is adjustable through gain control.

Ø The system has three automatic mixtures, which can be used real-time as well as post-acquisition for suppressing two variables simultaneously. Eg. For cancellation of tube support plate (TSP) or Baffle plate signal.

Ø Interactive display screens with several combination of strip-chart displays, vector displays and Zoomed strip-chart displays are available.

Ø Signals are automatically analyzed based on calibration curves.

Ø Sampling rate is very high which facilitates high-speed inspection of about 5 meters per second however the testing speed depends upon the sensitivity required.

Our Engineers are well trained in carrying out the test at Site and interpret the results accurately, depicting the actual condition of the tubes based on the test results, particularly very competent in resolving between defects and non-relevant indications.  The job was carried out by Level II qualified engineers. Around 2000 tubes were tested in 3 days.

Benefits of Eddy Current Testing:

v Avoid unnecessary shutdown due to tube leakage.

v Helps in planning/procurement of tubes/retubing activity

v Big cost saving

v Improved plant availability

No comments: