Abstract
Boiler feed pumps (informally termed as mini turbine owing to its criticality) in thermal power plants are prone to normal wear and tear over a period of time, which leads to loss of pump efficiency and sometimes accidental failures resulting in heavy damages and prolonged shut downs. Re-engineering approach using High Performance Coatings by Plasma & HVOF processes, has recently enabled to add new world-class dimensions by reclamation & complete overhauling of Boiler Feed Pump Internal Cartridges (6“ LL Pacific Pumps Inc USA and 200 KHI, BHEL, India make), in order to obtain increased life cycle, maintain pump efficiency, De-accelerated wear rate. This was accomplished by establishing perfect interrelationship of cartridge assembly, providing exacting tolerances to meet functional and assembly requirement, and incorporating international standards for protective wear shielding by Plasma & HVOF technology on wear prone critical components. This paper describes the Re-engineering methodology adopted to improve the performance of the Boiler Feed Pump with the help of surface modification using plasma and HVOF coatings on critical components showing wear patterns, which led to the development of proprietary ceramic and cermets coatings after extensive laboratory and field trials. The Reengineered Boiler Feed Pumps are showing superior performance at one of the major power generating unit in Central India.