MPY - Mils per Year

The term "MPY" describes the corrosion rate of a metallic surface. This is interesting for pipes or piping systems. The formula is used to calculate the material or weight loss of a metal when corroding. You will find detailed information here:

MIC - Microbiologically Induced Corrosion

"MIC" describes all corrosion caused by microbiological organisms such as bacteria. Some of these produce acids which harm metallic surfaces. If the microbes or bacteria settle in a so-called biofilm their influence even intensifies at this spot.

SRB - Sulfur Reducing Bacteria

SRB are Bacteria which live in the deep sea mostly around so-called "Black Smokers". They are anaerobe and can destabilize steel in pipelines or processing machines. If you are interested in further information please see this page:

COC - Cycle of Concentration

"COC" is a term used to describe a phenomenon in the cooling water. In an open cooling water system, the water constantly evaporates and fresh water is added. Substances as limescale, which have been solved remain in the cooling loop. Their concentration in the cooling water increases gradually. If the amount of foreign substances exceeds a certain level, the water has to be exchanged completely and the cooling loop is cleaned. The Cycle of Concentration can be used to define how often the water in the cooling loop can be pumped around before a blowdown is needed.


When writing about "Downstream Applications" we usually refer to Refineries and the Petrochemical Industry.


The applications we describe around the "Midstream Sector" include Trunk Lines and Crude Oil Terminals.


Our Upstream Applications include Wells, Flow Lines, the Gathering Station as well as Separation Plants.


Corrosion can be an issue where water is in contact with metal pipes. The topic is also interesting for the Oil and Gas business as the water contained in crude can be sufficient to cause corrosion in the pipelines. It harms the surface of the pipes and can erode the substance.

Open Cooling Water System

In an open cooling water system there is a certain type of exchange between cooling water and the environment. Either with the ambient air, as evaporation is used for cooling or by adding fresh, cool water to the system. Adding new water while used water evaporates Leads to a Cycle of Concentration as formerly solved substances remain in the system.

Closed Cooling Water System

In a closed cooling water system, the cooling water circulates without contact with the environment. It is cooled by a chiller or heat exchanger. These systems are used, where very low temperatures are needed or for very risky processes where the cooling must not be disturbed. Before entering the cooling loop the water is purified, therefore the risk for scaling or fouling is reduced. Nevertheless, corrosion can be an issue if the water is stagnating.

We use cookies to ensure that we give you the best experience on our website and to improve the relevance of our communications with you. If you continue without changing your settings, we’ll assume that you are happy to receive all cookies on the merusonline website. However, if you would like to, you can change your cookie settings or find detailed information about how cookies are used on this website by going to 'Data protection'.