A Case Study on the Failure Analysis, Prevention, and Control of Boiler Tubes at Elevated Temperatures

Abstract

Boilers in the power plant have to operate in highly strenuous conditions, where the service temperature can reach nearly the melting point of the materials. Boiler tubes inside the boilers have to face high stresses, a fluctuating environment, and high temperature. All these factors will activate various degradation mechanisms in the heat exchanger tubes, which results in their catastrophic failure. Due to this, the boiler will fail to meet its functional requirement, and consequently, in this event, the power plant will remain shut down for an extended period, resulting in a substantial economic loss to the organization. More than 75% of unexpected boiler shutdowns are due to the failure of the boiler tubes. This article discusses a failure associated with the boiler tubes inside an industry at Hoshiarpur, Punjab, India. Frequently occurring failures of boiler tubes were the cause to identify the right reasons responsible for these failures and then provide the technical solutions in the interest of the industry. During the detailed investigation, it was found that the wall thinning of boiler tubes was occurring due to high-temperature oxidation and erosion, and they could not withstand the internal pressure, leading to the bursting of tubes. Use of high-temperature oxidation- and erosion-resistant thermal spray coatings were recommended to the industry to avoid the failure of boiler tubes.