How to convert Btu/h units? To be honest, the Btu/h single is really rare. On the mainland side, the common cooling units are kcal/h, W, kw, cold ton, etc. Some people like to use "HP, P, and horse." In fact, horses are power units, not refrigeration units! 1 horse = 735W, but in the refrigeration industry, people often use the number of horses to describe the cooling capacity of refrigeration equipment, so non-industrial people may not understand, given below the conversion relationship of various refrigeration units for your reference.
Conversion between cooling units:
1. 1 horse = 2.5kW (for air-cooled units), 1 horse = 3kW (for water-cooled units)
2. 1Btu/h (British thermal unit/hour) = 0.2931W, 1W = 3.412 Btu/h;
3. 1USRT = 3024kcal/h, 10000kcal/h = 3.3069USRT;
4. 1kcal/h=3.968Btu/h, 1Btu/h=0.252kcal/h;
5. 1USRT (United States cold ton) = 3.517kW, 1kW = 0.28434USRT;
6. 1kcal/h (kcal/hour)=1.163W, 1W=0.8598kcal/h;
Metric and Imperial Instructions:
1. "Pig" is used for power unit, expressed by Hp (imperial bank) or Ps (metric system), also called "horsepower", 1Hp (imperial bank) = 0.7457kW, 1Ps (metric system) = 0.735kW;
2. In the refrigeration industry, the cooling capacity of small and medium-sized chillers will also be commonly referred to as “patchâ€, while the cooling capacity of large-scale air-conditioning chillers is often expressed as “cold ton (US ton of cold tonnage)â€.
Screw chiller cooling capacity from 92880Kcal / h to 744760Kcal / h, compressor power from 8KW-1280kw, can be widely used in refrigeration is particularly large in all walks of life, a variety of models to choose from. When we choose screw chiller, we should pay attention to what issues! Lets come look:
1. The selection of the screw chiller should be based on the cooling load and where it is intended to be used. For a refrigeration system with a low-load operating condition for a long time, it is suitable to choose a multi-head piston compressor group or a screw compressor group for easy conditioning and energy saving, which is what we often call a double-head screw chiller. With changes in the load, the chiller automatically determines the number of start-ups and ensures that the open compressor is in optimum working condition, thereby effectively saving energy.
2. When using a screw chiller, priority is given to the unit with a high coefficient of performance. According to the statistics of the past, normal chillers are operating under 100% load for less than 1/4 of their operating hours throughout the year. The proportions of running time for 100%, 75%, 50%, and 25% load during the sub-run time were approximately 2.3%, 41.5%, 46.1%, and 10.1%. Therefore, the chiller model with a relatively flat efficiency curve should be given priority when selecting chillers. At the same time, when the design is selected, the adjustment range of the chiller load should be taken into account. The multi-head screw chiller has excellent part load performance, and the screw chiller can be selected according to the actual conditions of the factory.
3, when using screw chiller, should pay attention to the conditions of the nominal conditions. The actual cooling capacity of a chiller is related to the following two points:
a, cold water outlet temperature and flow;
b. Cooling water inlet temperature, flow rate and fouling coefficient.
4. When selecting a screw chiller, one should pay attention to the normal working range of this type of screw chiller, mainly the current limit of the motor is the current value of the shaft power under the surface conditions.
5. When designing the screw chiller, it should be noted that: Under nominal operating conditions, the outlet temperature of cold water should not exceed 15°C, and the outdoor dry bulb temperature of the air-cooled unit should not exceed 43°C. If it is necessary to go beyond the above categories, when it is understood whether the use of the compressor can be allowed, the power of the allocated motor can be sufficient.
The main components of the screw chiller are all imported configurations: its main core components are compressors; international brands such as Bitzer in Germany, Copeland in the United States, and Hanbell in Taiwan; and other 80% refrigeration in addition to the two devices. The components use the international famous brands such as American Danfoss, American Alco, French Carly, American Emerson, etc.; combined with scientific and rigorous construction process; ensure the safety and reliability of the refrigeration system. The use of the latest CAD/CAM processing technology, with CNC machining center production, compact structure, high reliability, stable performance, beautiful appearance, high efficiency and energy saving. The advanced automatic control system is configured; the 24-hour continuous cooling of the process can be achieved.