A cooling tower is an installation that retreats heat from water by evaporation or conduction.
The industries use cooling water in various processes. As a result, there are also various types of cooling towers. There are cooling towers that create process water that can only be used once, before it is discharged. There are also cooling towers that create water that can be reintoduced in the production process.

Freshwater or central cooling system: Fresh water is used in a closed circuit to cool down the engine room machinery. The fresh water returning from the heat exchanger after cooling the machinery is further cooled by sea water in a sea-water cooler.
As discussed above, in the central cooling system, all the working machinery on ships are cooled down using circulating fresh water. This system comprises of three different circuits

As discussed above, in the central cooling system, all the working machinery on ships are cooled down using circulating fresh water. This system comprises of three different circuits

The most common central cooling system is a split system, which includes an outdoor cabinet containing a condenser coil and compressor, and an indoor evaporator coil, usually installed in conjunction with your furnace or air handler. The compressor pumps a chemical called refrigerant through the system.
emperature control of the process can be affected using electric, pneumatic, electro-pneumatic and self-acting controls. This Module details some common applications including process vessels, heat exchangers and high temperature fail safe control.
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Taipeiplas 2018

Taipeiplas 2018

「靖達精密科技有限公司」創立於1952年,超過六十年的歷史,一直致力於冷凍技術與產品品質的提升。在海外銷售超過40個國家,並以「創新精進、服務迅速、品質第一、顧客至上」為標準的服務宗旨,為每位客戶提供最優良的品牌形象與最周全的服務,在工具機,橡塑膠,半導體及整廠冷卻系統規劃,堅持不斷研發及創新。

Temperature controllers are needed in any situation requiring a given temperature be kept stable. This can be in a situation where an object is required to be heated, cooled or both and to remain at the target temperature (setpoint), regardless of the changing environment around it. There are two fundamental types of temperature control; open loop and closed loop control. Open loop is the most basic form and applies continuous heating/cooling with no regard for the actual temperature output. It is analogous to the internal heating system in a car. On a cold day, you may need to turn the heat on to full to warm the car to 75°. However, during warmer weather, the same setting would leave the inside of the car much warmer than the desired 75°.

For example, in a temperature control system, a high fixed alarm prevents a heat source from damaging equipment by de-energizing the source if the temperature exceeds some setpoint value. A low fixed alarm, on the other hand, may be set if a low temperature could damage equipment by freezing.

Temperature controllers are measurement devices used for temperature control. Dividing into thermocouple-type and resistor-type, the electronic temperature controllers obtain the temperature change from the sensor and send the measured data to the electronic processor. The output device will then control the temperature variation within a specific range.

Due to the fact that water is environmentally safe, abundant, easy to handle, and provides much better heat transfer than air, it is the most practical and commonly used medium for cooling of industrial processes. However, the effective use of water for cooling applications results in challenges in design and operation. Most components in a cooling water system are constructed from metallic materials, especially heat transfer equipment. These components can suffer failures due to many forms of corrosion, cracking, and other damage mechanisms. Nonmetallic components in the cooling water system may also experience degradation and failure. The varied types of damage are caused by differences in cooling water system design, temperature, flow, water chemistry, alloy composition, and operation.

A temperature controller is an instrument used to control temperature calculating the difference between a setpoint and a measured temperature. The controller takes an input from a temperature sensor and has an output that is connected to a control element such as a heater or fan.

To accurately control process temperature without extensive operator involvement, a temperature control system relies upon a controller, which accepts a temperature sensor such as a thermocouple or RTD as input. It compares the actual temperature to the desired control temperature, or setpoint, and provides an output to a control element. The temperature controller or thermostat is one part of the entire control system, and the whole system should be analyzed in selecting the proper equipment.