WHEN WATER IS NOT WELCOME

The perils of high humidity have been a matter of concern across industries. Even refineries and power plants are immensely plagued by the moisture menace. It intervenes with various processes and can even extend the completion time of the project, which, in turn, translates into a heavy financial burden on the company.

Dehumidification solutions for surface preparation

Humidity has a deterring effect on industries. It interferes with the already complex surface preparation and coating processes, thereby offering resistance to the overall accomplishment of the task. If the industry experts are to be believed, 60 to 80 percent of premature coating failures result from inadequate surface preparation. Here, exposure to moisture triggers condensation on the blasted surface, giving rise to a phenomenon called ‘flash rust’. This makes it difficult for the coating to properly adhere to the substrate surface. Consequently, painting done on the condensed surface leads to blistering and delamination, where blooming and peeling problems keep recurring throughout the paint jobs. Also, the inadequate adhesion of the coating to the substrate is responsible for shortening the life of the coating system. Hence, it gives rise to the need to repeat the entire coating process all over again.

Hence, looking at the complications arising due to humidity, deploying dehumidification solutions can vouch for proper surface preparation for coating application. It is the simplest and most cost-effective technology that efficiently eliminates moisture during a blasting and painting job. The advanced technology is adept at achieving and maintaining humidity at the required level for inhibiting the process of condensation and rust blooming on the surface.

The crucial role dehumidifiers play

Desiccant dehumidifiers maintain the relative humidity (RH) at less than 55 percent inside the tank throughout the blasting, painting, and coating processes. Additionally, they also maintain a constant -5° C dew point differential between the air and the surface to be coated, and a -12° C difference between the air inside the tank and outside.

Hence, dehumidifiers play an instrumental role in preventing condensation on the surface, which, in turn, alleviates inter-coating delamination and enhances curing properties. By ensuring a strong inter-coat adhesion, the advanced solution invariably increases the coating life. Considering the adverse effect of moisture, the coating process is halted at night during monsoons or high-
humidity climatic conditions. Especially at night, the chances of condensation are very high due to the cold weather, ultimately encouraging corrosion and blooming on the surface. Additionally, dehumidification solutions on rent come in handy and allow for the coating process throughout the year, irrespective of the weather conditions outside.

For timely and quality completion of the project

It can, therefore, be said that dehumidification can immensely contribute to reducing the downtime of the plant, ultimately leading to the timely completion of the project. In addition to this, it aids in blasting of the entire surface in a single go, permitting an uninterrupted coating process on the surface. This is otherwise done in a phased manner in the absence of a dehumidification system, which is neither practical nor economical. In turn, it also eliminates the need to repeat the coating process, which arises due to the coating failure. All the factors together contribute to reducing the project time and cost.

Considering that blasting and painting processes are carried out in a confined space, they can pose severe health risks to the people working inside. Here, the dehumidification system becomes all the more essential as it provides ventilation solutions that create comfortable working conditions by providing fresh air inside the confined area. The technology increases productivity as well as the safety of the workers.

Conclusively, the dehumidification solutions are well-equipped with multi-faceted benefits, including ensuring the safety of the workers and the continuity of complex processes. They are highly sought by the industry players to reduce downtime
and add to the profitability of the company by ensuring timely and quality completion of the project.

Dehumidifiers play an instrumental role in preventing condensation on the surface, which, in turn, alleviates inter-coating delamination and enhances curing properties. By ensuring a strong inter-coat adhesion, the advanced solution invariably increases the coating life.

Source: Pahwa Group

DEEPAK PAHWA                      Director Technical Drying Services Pahwa Group

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