Contributed
Creation of maintenance envelope for cooling systems at electronic units

The aim of this work is to describe maintenance envelope methods for cooling systems at electronic units in many industries. Cooling systems based on ethylene glycol coolants are critical at electronic units. Unfortunately, they are not always treated appropriately. These systems are sometimes very complex and consist of a large quantity of different materials. The amount of coolant in such systems can reach thousands of liters. Corrosion of metallic materials in cooling systems may result in sudden cessation heat transfer and failure of all elements in an electronic system. Such situation is critical because life of people depends on the correct function of electronic devices. Therefore, complexity and criticality of cooling systems require their proper maintenance.
Most analytical methods for testing coolants based on the ethylene glycol were developed in the 1980s. Since then, this coolant has not received proper attention despite the obvious need and development of new analytical instruments. In addition, there was a need to build a maintenance strategy for cooling systems that includes preventive maintenance based on advanced analysis and proactive maintenance for constant improvement of the cooling system function. The main goals in the cooling systems are prevention of the deterioration of chemical properties of the coolant and the beginning of corrosion.
New physicochemical tests, based on understanding of corrosion processes in electronic cooling systems were created. Maintenance envelope of these cooling systems was developed that allowed eliminating deterioration of coolant and corrosion, and thus drastically reducing the total maintenance cost.

Keywords: corrosion, cooling system, ethylene glycol, analytical methods, maintenance.