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Ebara Engineering Review No.251

Under the Scenes of our Lives
High-pressure pump - Role and Application -

High-pressure pumps, rarely seen in our everyday life, are working hard in places for producing unexpected familiar things as well as materials for such things.

Under the Scenes of our Lives
High-pressure pump - Technologies and Structure -

In order for a high-pressure pump to operate stably in the place where it should play its role, it must provide an excellent balance and endure high pressures. These requirements are specific to high-pressure pumps. High-pressure pumps are based on technologies for achieving these requirements. This article outlines these technologies and how they are related to the structure of high-pressure pumps.

Boiler Feed Pump

In a thermal power plant, the boiler feed pump (BFP) is one of the critical auxiliary machines that are equivalent to the heart of the plant. In pace with the increases in the capacity of equipment for thermal power generation, improvements to adapt to higher temperatures and pressures, and changes in operation method, BFPs have been improving and advancing. This paper explains how BFPs have been upsized and made compatible to higher pressures; main specifications of BFPs; structures and materials of typical BFPs for conventional supercritical thermal power plants and for combined-cycle thermal power plants; characteristics of the shaft seal and bearing; technological development for higher capacities and performance; actual development and delivery of 100%-capacity BFPs; improvements to the structure design for increasing the stress resistance of BFPs so that they can adapt to more severe conditions in the operation of thermal power plants associated with the spread of renewable energy; and examples of efforts to streamline the BFP design for manufacturing cost reduction and space saving.


Feed water pump, High pressure, Efficiency, Super critical thermal power, Combined cycle thermal power, Reliability, Specific speed, Shaft strength, Bearing, Double casing

Numerical Simulation of Welding Deformation produced in Compressor Impeller

Among many problems with welding is welding distortion. Since welding distortion significantly affects the performance and reliability of products, it has become increasingly required in recent years to appropriately foresee, control, and reduce distortion. One of the approaches to this issue is numerical analysis. As significant improvements have been made to welding distortion analysis technology, its application has been increasing every year. So far, however, numerical analysis has only been applied to a limited number of large scale and/or complicated structures. Under such circumstances, with a compressor impeller having complicated structure as a target, distortion analysis and experiment was performed. The analysis and experiment results have revealed that it is possible to evaluate welding distortion occurring to an impeller with high accuracy by using numerical analysis with the help of the construction of a heat source model and taking into account phase transformation.


Compressor, Impeller, Welding distortion, Numerical simulation, Distortion measurement, Phase transformation, Martensitic stainless steel, Displacement of discharge width, Displacement of cover height

Application of In-situ Observation Technologies in CMP Process for Upgrading the Process Integrity

In developing a basic understanding of what is happening during the chemical mechanical polishing process, evaluation techniques based on in-situ (in-liquid) observation are useful. Compared with in-air measurement, in-liquid measurement is often very difficult. Chemical mechanical polishing is a wet process, which absolutely requires evaluation based on in-liquid measurement. In this study, we tried three different evaluation techniques based on in-liquid measurement that uses light and a probe in order to analyze the surface reactions and behavior of abrasive particles during the polishing process. As a result, we determined that these techniques can be used as useful evaluation methods. In this paper, we describe the observation results with the hope that we can popularize these in-situ (in-liquid) evaluation techniques.


Chemical mechanical polishing, In-situ, Ellipsometry, Fluorescent microscopy, Kelvin probe, Surface reaction, Abrasive particle, Fluorescent particle, Benzotriazole, Wet process

Report on Delivery and Operational Condition of Large-scale Grate-type (Stoker-type) Incinerator in Nanchang City, Jiangxi, China

Ebara’s grate-type waste incinerators with a treatment capacity of 1200 t/d were delivered to Nanchang city, Jiangxi, China, and their performance test was completed in August 2015. In the past, Ebara Environmental Plant Co., Ltd., and Ebara Qingdao Co., Ltd., delivered incinerators to five facilities in China: fluidized-bed incinerators to two facilities and grate-type incinerators to three. Among them, two grate-type incinerators have been reported in the Ebara Engineering Review. This time, we delivered incinerators to the sixth facility, with the biggest capacity per unit among all grate-type incinerators delivered by Ebara, including those under construction or commissioning.
This paper describes the engineering refinement and improvements for upscaling and the NOx control effect of a flue-gas recirculation system, along with the operation status so far and performance test results.


China, Waste, Incinerator, Stoker, Calorific value, Combustion, Environmental, HPCC, Qingdao, Nanchang