UDC Non-Destructive Testing Services

Non-Destructive Testing Services

A variety of non-destructive testing procedures are available through UDC to assess the present condition and integrity of boiler circuitry, headers, and drums. The following include but are not limited to:

» Ultrasonic Testing (UT)

» Oxide Thickness Testing

» Magnetic Particle Testing (MT)

» Dye Penetrant Testing (PT)

» Eddy Current Testing

» Header Replications

» Weld Inspections (CWI)

CWI Capabilities
Interpret drawings and other documents. Verify that the base materials and consumable welding materials conform to the specifications and that welding filler metals used are as specified for each base material or combination of base materials. Verify that the welding equipment to be used for the work is appropriate for use with the welding procedure and has the capability to meet the applicable requirements of the welding procedure. Verify that the welding procedures are as specified and are qualified, and that the welding is performed in conformance to the applicable procedure. Witness performance and testing of procedure qualification test assemblies, or supervise these activities when performed by outside agencies. Verify documentation of procedure qualification test results. Verify that welders, welding operators, and tack welders have been qualified in conformance to the applicable standards, and that they are qualified to use the welding procedures specified for the work. Witness testing of the welder test assemblies and/or welding operator qualification test assemblies, or supervise these activities when performed by outside agencies. Verify documentation of performance qualification test results. Require re-qualification if there is evidence the welder's or welding operator's work does not conform to the requirements of the applicable standard. Require re-qualification if the welder's or welding operator's qualification is not current.

New CFB Boiler UT Mapped for Baseline Data

A current UDC customer recently commissioned a 125 MW Circulating Fluidized Bed Pyropower

boiler. As part of an aggressive preventive maintenance program, UDC was retained to supply a Boiler TRACKER Failure Management System.

History has demonstrated that a primary failure mechanism for this design boiler is erosion thinning of boiler tube walls. Since this station was brand new, a UDC Inspection team was employed to develop a mapping scope of work. Once the work scope was developed, an inspection team executed the plan by sampling and logging over 9,000 individual thickness data points for entry into the TRACKER system. This project was completed in just three days by a team of nine technicians.

Why was a new boiler mapped? All new tubes are designed on a minimum nominal thickness. In many instances the actual thickness will exceed the design nominal by a considerable margin. If actual thickness values are utilized to establish a baseline, then the actual thinning rates can be accurately projected. The alternative would require at least two cycles of outages and mapping before meaningful projections could be made. This could represent a year or more delay in identifying potential areas of accelerated degradation.

In this example, our customer required more than a UT mapping contractor. The UDC Inspection Team brought years of boiler maintenance experience to bear in establishing and executing a reasonable and manageable work scope.