Chemical recovery is a highly pressurized process. Variations in the process conditions may gradually bring about thermal and mechanical stresses in the recovery boiler's tube structures. If not identified early enough, cracks in the metal structure develop into leaks and may cause severe reactions between water and smelt bed -and, at the worst, even an unexpected explosion. Such a development is a nightmare to any boiler operator -resulting in perished lives and capital losses.
The conventional way of following up the condition of high-pressure steam and water tubes is to carry out periodic visual and audible inspections. This method clearly indicates leaks already arisen but does not reveal the preliminary signs of fatique in materials or inactive cracks.
Early identification of stress areas and cracks is the way to control evitable problems. On-line acustic emission monitoring of the boiler offers an innovative solution that will effectively detect boiler tube damages before they are really even born. This cracking indicator system performs as a preventive maintenance tool for the recovery boiler operator and helps stopping non-welcome suprises. It also notifies the boiler operator of arising cracks well in advance. Working 24 hours a day, it provides on-line information of the origin and growth of structural defects. It also facilitates early detection of even the smallest tube leaks in economizers and superheaters, which is critical when optimizing risks for further damage in other tube sections. An instant alarm of a leaking crack facilitates a controlled boiler shutdown and minimizes damages. Thus, more serious equipment failures and costly extra shutdowns can be avoided. Providing the boiler operator with non-stop information about structure conditions, the CI (Cracking Indicator) system improves boiler safety crucially. It helps extending the lifetime of your recovery boiler and is an indispensable tool to cut down maintenance and repair costs.
We look forward to have the possibility to highlight some of the practical cases observed using CI System during the conference in Copenhagen May 26-20 1998.
Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00
Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:
Publication Contact:
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