Inner UT System for Boiler Tubing

Introduction

The tubes of superheater, reheater and economizer in the fossil-fuel fired boiler are inspected periodically by conventional ultrasonic method as part of in-service inspection. Most tubes are located high on the boiler and are difficult to inspect tubing. In addition, scale removal for preparatory work in inspection of boiler tubes requires much work.

To improve the efficiency and reliability of inspection of boiler tubes, an advanced system for inspecting boiler tubing by an ultrasonic method from the inside of the tube was developed.

Characteristics

·       The boiler tubing at the restricted space can be inspected.

·       Polishing, scaffolding and working in the furnace are not necessary.

·       Full length of tubing can be inspected.

Introduction

The tubes of superheater, reheater and economizer in the fossil-fuel fired boiler are inspected periodically by conventional ultrasonic method as part of in-service inspection. Most tubes are located high on the boiler and are difficult to inspect tubing. In addition, scale removal for preparatory work in inspection of boiler tubes requires much work.

To improve the efficiency and reliability of inspection of boiler tubes, an advanced system for inspecting boiler tubing by an ultrasonic method from the inside of the tube was developed.

Thickness range                                : 2 to 20 millimeter

Inside diameter of tubing                  : 21 to 50 millimeter

Maximum allowable tubing length   : 100 meter

Accuracy                                           : ±0.1 millimeter

Inspecting rate                                   : 0.3 to 3.0 meter/minute

System

Principles

Output Samples

Inspection records

94 boilers (1989 to 2003 year)

Source: Mitsubishi Hitachi Power System (MHPS) Japan