Welcome To UTPedia

We would like to introduce you, the new knowledge repository product called UTPedia. The UTP Electronic and Digital Intellectual Asset. It stores digitized version of thesis, dissertation, final year project reports and past year examination questions.

Browse content of UTPedia using Year, Subject, Department and Author and Search for required document using Searching facilities included in UTPedia. UTPedia with full text are accessible for all registered users, whereas only the physical information and metadata can be retrieved by public users. UTPedia collaborating and connecting peoples with university’s intellectual works from anywhere.

Disclaimer - Universiti Teknologi PETRONAS shall not be liable for any loss or damage caused by the usage of any information obtained from this web site.Best viewed using Mozilla Firefox 3 or IE 7 with resolution 1024 x 768.

STUDY ON THE EFFECTIVENESS OF INORGANIC CORROSION INHIBITOR FOR MILD STEEL IN COOLING WATER SYSTEM

CHANG, YEE JIAN (2017) STUDY ON THE EFFECTIVENESS OF INORGANIC CORROSION INHIBITOR FOR MILD STEEL IN COOLING WATER SYSTEM. IRC, Universiti Teknologi PETRONAS.

[img] PDF
Restricted to Registered users only

Download (4Mb)

Abstract

Corrosion of pipes in cooling systems is a serious problem in the industry which has led to the loss of pipeline integrity, increased maintenance cost and even unplanned shut down due to pipe leakage etc. With the rise of restrictions on the use of toxic chromate-based inhibitors in aqueous systems, industries have shifted their focus towards research on the less toxic soluble molybdate (MoO42–) and nitrite (NO2-) compound as an alternative corrosion inhibitor (CI) for steel. Therefore, this research aims to design and develop test jig for rotating cage test and mini flow loop test in order to determine the corrosion rate (CR) and effectiveness of CI for mild steel in different concentration under the influence of flow velocities of 0.3 m/s and 1.2 m/s, which are to simulate industries near stagnant condition and normal operating condition respectively. The final objective of this project is to analyze the microstructural surface of the corroded specimen to identify the corrosion behavior. Corrosion test by weight loss method using rotating cage and mini flow loop set up were carried out using simulated cooling water (SCW) as per ASTM G 170 and ASTM D 2688 respectively using mild steel sample AISI C1018. Steel specimens were machined and cut into strips then grinded and polished and later mounted to the rotating cage and mini flow loop rack for the corrosion test. For 1.2 m/s and 0.3 m/s flow velocity testing, the highest mean corrosion rates were 1.69 mmpy and 0.425 mmpy for uninhibited SCW respectively, whereas lowest mean corrosion rates were 0.006 mmpy and 0.005 mmpy for addition of molybdate and nitrite into SCW respectively. CI efficiency ranges from 93.5 – 99.7%. Higher flow velocity deemed to have more pitting on specimen surface for uninhibited SCW which could be caused by the disruption of the protective oxide film formation on the specimen. CR of mild steel in inhibited SCW was not impacted by higher flow velocity. Combination of molybdate and nitrite a corrosion inhibitor is the most efficient to mitigate corrosion for mild steel regardless of velocity.

Item Type: Final Year Project
Academic Subject : Academic Department - Mechanical Engineering - Materials - Engineering materials - Metals alloys - Fabrication
Subject: T Technology > TJ Mechanical engineering and machinery
Divisions: Engineering > Mechanical
Depositing User: Ahmad Suhairi Mohamed Lazim
Date Deposited: 01 Aug 2018 09:54
Last Modified: 01 Aug 2018 09:54
URI: http://utpedia.utp.edu.my/id/eprint/17936

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...