vn en



Some issues when designing, installation and using cold storage

10:26 AM | 24/10/2013

Some issues when designing, installation and using cold storage such as: wet slip phenomenon, the phenomenon air slip, circulation in cold storage, slitting cooler ....

Air in cold storage have low temperature, when air circulate through the indoor unit, the  significant amount of water has to stop, so the distribution of water vapor pressure in the air chamber smaller than outside. As a result, tend of moisture is penetration into the room through the cladding.

For warehouse, the moisture can penetrate and make insulation wet, thereby diminishing the nature of the insulating material layer. Therefore warehouse have to be tarred and waterproof tar paper liner. Waterproofing wax paper lined 02 required classes, courses must overlap on each other and taped closed, continuous membrane Cuisine on the entire area of ​​flooring.

For panel storge, outside and inside of warehouse have the religion classes, therefore moisture don’t have the ability to reach. However, to avoid sharp objects puncturing the shell panel leads to wet insulation, so in the cold storage as it is often the system of wooden pallets to avoid the trolley panel, sharp objects hit the carriage during displace. Between the panels have a small slits should be sealed with silicone sealant when assembled. Outside the warehouse in factories they buried the range of about 0.8 m high column preventing the truck bumps into cold storage damage.
* The phenomenon of tray foundation due to ice:

Prolonged cold storage warehouse, cold transmission through structural insulated to ground. When the low temperature crystallization of water into ice, this process creates a long accumulation of large rocks as cold storage tray background, destroying building structures.

To prevent the phenomenon tray platform using the following measures:

Create a space below for background ventilation: Installation of cold storage on the eel, or on the stent system.

The ventilation are built with concrete or bricks, high about 100 to 200mm to ensure good ventilation. The maximum distance between ventilations 400mm. The surface slope on either side of 2% to avoid sweating (Figure 2-7). Using a resistor to ground drying. Simple measures, easy to install, but operating costs are quite high, especially when large size warehouse. So this method rarely used.Use the vent pipe for foundation: For warehouse have foundation, to avoid freezing the foundation, most economic measures is the use of foundation ventilation duct. The ventilation tube about 100mm, layout distance about 1000mm to 1500mm.

In the process of working on the wind through pipes, heat exchangers and heating to the ground floor, to prevent freezing.
* The phenomenon of air slip

When you import export operation or open warehouse for test, the outside air will infiltrate warehouse caused significant heat damage and affect maintenance mode. This penetration process shall be as follows: Wind moving hot outside air from above into the warehouse door and cold air rushed out of the room in the background. The process of penetration of outside air into the cold storage not lose your cool room but also bring moisture into a room and then accumulate on the indoor unit affects the working efficiency of the system.

To prevent this phenomenon many people use various methods:

+) Use fans to create screen monitor air exchange to prevent outside and inside air.

+ Double Door: Doors Cold Storage has 02 separate layers makes the air inside information never outside. This method accounts for more inconvenient for the area, exporting goods difficulties, reduced aesthetic works so rarely used. Many large cold storage system would make it a buffer stock. Buffer stock has moderate temperatures, which acts as the buffer layer to avoid the outside air from entering the cold room (Figure2-8).

+) Making the door

+ Using a small window to enter the restaurant. The door is mounted on the wall at the appropriate height and the size of 680x680mm

+ Use plastic monitor: Door Hanging 01 plastic panels are assembled from smaller pieces. This method is relatively high efficiency, but does not affect the movement.

Plastic curtains made ​​to ensure good cold tolerance and high durability. Doors are assembled from plastic strips 200mm wide, the eyelid fold up a distance of at least 50mm, ensuring convenient travel but when there are people in the curtain still closed (Figure 2-9).

To create favorable conditions for the room air circulating in the design and use should pay attention to the following:
 * Arrange good sensible

Arrangening goods in storge have to according to conditions as following:

  • Convenient for the ventilation in warehouse in order to all the blocks of goods are cooled
  • Convenient for inspestion and consideration
  • Goods layout on each block, avoid lying discrete greater ability to reduce water evaporation goods quality.
  • When sorted inventory must be taken to contain the logical gap between shipments and between shipments and the walls, ceiling, flooring letting air flow and refrigeration products. For wall to wall warehouse loading some also work for customers not inclined leaning on the wall, as this may inflate if the insulation panels too heavy. The minimum distance of the concrete above the table 2-8.
  • In the warehouse must contain the necessary clearance for loading and unloading vehicles and travel. Width depending on the method of loading and unloading and the actual device. If the narrow gap when vehicles collided at the restaurant can shed blocks unsafe and damaging products. Underneath the cooler should not arrange the operators in order to easily handle when needed.
  • For large cold storage with large capacity needed to use the wind to distribute the channel winds are in stock. Base on the wind channel system reasonably designed wind will be more evenly distributed to many locations in the warehouse.

    Defroster cooler
  • When shifting through the air cooler, water vapor condenses part in it. Accumulation process as long as the thick layer of snow. The cooler sticking snow in the incident leading to cooling systems, such as cold storage temperature is not satisfactory, long cooling time, flood service, fire motor etc. ...
  • The snow that clung to form external cooler insulation prevents heat transfer between the refrigerant and air-conditioned chamber. So cold temperature chamber unsatisfactory, prolonged cooling period. On the other hand refrigerant in the cooler temperatures due to not getting vaporized so, a large amount of moisture is causing the compressor suction liquid flooded compressors.
  • When the snow stick of sugar circulating in cooler wind blockage, reducing air flow, heat exchange efficiency also decreases with, big hindrance overworked fan and motors can burn.
  • In some cases snow clung too thick makes friction blades spin and will not be burnt, broken fan.
  • To discharge the snow for cooler people often use the following 3 methods. Gas heater: This method is very effective because the exhaust heat from inside the band perform. However, the method is discharging hot gas ice hazard due only done when the system is operating, the exhaust ice in the cooler boiling process occurs can strongly entrained liquid in the compressor. So should only be used in small systems or systems with low pressure tank. Rinse with water ice: water method using high efficiency, easy to implement especially in large systems. On the other hand when it discharged water ice made ​​out smoking and stop the compressor station before discharging liquid submerged ice should not fear being discharged ice.
  • However, when the ice discharge, water can splash out the product in cold chamber and diffuse into the air in the room, increasing its moisture, moisture continues to cling to the cooler during operation next release. So often measure water use for large systems, many clinging snow, for example, in the frozen system.
  • Like water defroster cooler method,using resistive method not afraid submerged liquid. On the other hand in ice discharge resistors does not increase the humidity in the warehouse. However, the method used resistive power costs large and not easy to implement. The resistors are only available installation done by the manufacturer.

Other service