Air coolers are heat transfer units meant for cooling of air, which circulates in electric machines. They can be both the surface type and mounted.
- Surface type air cooler (ВУП, ВОП, ВО) cools air in electric motors, turbo – and hydrogenerators, exciters etc.
- Mounted air cooler (ВБ) is meant for motors with closed ventilation cycle cooling.
Air coolers operating principle is in heat transferring from warmer substance to less warm one through heat-conducting surface. In prctice it is as follows: air heated in electric machine, touches a finned tube with cold water and transfers its heat to the tube. Structure of water chambers provides several cycles of water flowing and thanks to it the air cooling is quick and effective. Standard air cooler is a tube bundle, which consists of finned tubes. All of them are hermetically bulkheaded into end piped plates to avoid cooling water penetration into passing airflow. The covers with inlet and outlet connections are mounted on the plates by means of tight water gaskets. There are special plugs in air coolers, which provide gas purging and blow down. Each type is equipped with hoisting device and device for transportation. Air cooler’s mounting is to be done according to the rules and with observation of occupational safety. During the installation process avoid water to be on electrical coils of the equipment. Water is connected from the side of gas purging (counter flow rule). The following technical characteristics should be taken into consideration when choosing the necessary model:
- Air consumption;
- Water consumption;
- Temperature of cooled air;
- Temperature of refrigerating water;
- Construction hydrodynamic and aerodynamic drag;
- Heat flow;
- Water working pressure;
- Air cooler’s weight;
- Single/multi pass arrangement.
Furthermore, air coolers can vary according to the supporting pipes’ material and constructional version:
- Flanged (marking Ф);
- Vertical on rollers (В);
- Horizontal on rollers (Г);
- Suspendable on rollers (П).
