The compressor is the core of the refrigeration system. Compared with land-based air conditioners, the compressor of marine air conditioners runs in a tilt and swing, and the oil supply problem is more prominent. Poor oil supply will cause serious damage to the compressor. The deep oil tank design ensures the oil supply of the compressor in the inclined and rocking environment on the ship. The anti-corrosion of the compressor is sprayed with special anti-corrosion paint for the navy after the outer surface is sandblasted.
The condensers of marine air conditioners are divided into two types: seawater water-cooled and air-cooled condensers. The seawater condenser is directly cooled by seawater, which needs to prevent the strong corrosive seawater corrosion and the smoothness of the refrigerant supply when the hull is swaying, while the air-cooled condenser needs to be protected from salt spray corrosion. The water-cooled condenser uses the Bfe10-1-1 heat transfer tube with strong corrosion resistance, the end cover is made of cast aluminum bronze, the tube plate is made of (HA177-2A/16MnR) composite material, and the safety valve is added to ensure safety. Potential corrosion equipment. For the liquid supply problem of the water-cooled condenser, add a liquid storage bag at the lower part of the condenser. The air-cooled condenser adopts a steel sheet sleeve steel pipe heat exchanger to improve the salt spray resistance.
Marine evaporators are also divided into water-cooled and air-cooled, and anti-corrosion still needs to be considered. The water-cooled evaporator adopts a dry shell-and-tube evaporator, which is the same as that used for land use. However, anti-corrosion measures on the outer surface of the evaporator must be considered. A plated steel shell is added to the outer surface to enhance the corrosion resistance of the evaporator. The air-cooled fin evaporator adopts high-efficiency steel tube sleeve type.
In addition to the throttling function, the expansion mechanism also functions to regulate the flow of refrigerant entering the evaporator. At present, the external balance thermal energy expansion valve is generally used in marine air conditioners.
The main components of the refrigeration system are filter driers, oil storage tanks, gas-liquid separators, solenoid valves, sight glasses, pressure gauges, shock absorbers, high and low pressure protectors, etc., which are used to better detect the operation of the system and protect the operation of the system. Safety and reliability. Among them, the fittings of marine air conditioners, such as sight glasses, should be connected with threads as much as possible to avoid welding. The solenoid valve of the marine air conditioner needs to be equipped with a manual control lever.
◆Selection of fan and motor
Anti-corrosion and anti-tilting factors should still be considered for marine fans and motors. The impeller of the marine air conditioner fan is required to undergo strict dynamic balance correction and overspeed test. The impeller is made of anti-corrosion aluminum alloy casting, and the casing is welded as a whole to meet the ship's requirements for strength, impact and corrosion. The selection of marine motors except when the ship is periodically tilted up to 45°. It is required that the motor can work reliably, and can still work without damage when the long-term horizontal and vertical tilt reaches 15°, and it must be equipped with a filter to prevent electromagnetic interference.
◆Marine duct design
The main features of the circulating air piping system are small space, large heat generation, and very limited space on board. When designing the wind pipeline, it is necessary to fully consider the wind pipeline vibration isolation, shock absorption, noise reduction, minimize the resistance loss, adjust the air volume and the actual space layout of the ship. The air inlet and outlet should be provided with return air boxes respectively. In order to reduce the vibration transmission during the operation of the special air conditioner, a small piece of soft pipe is connected between the rigid air pipe and the air inlet and outlet ports of the air conditioning equipment.
◆Design of cooling sea water pipeline
The ship's cooling water uses highly corrosive seawater, and the seawater cement sand content is relatively high. Generally, the cooling sea water flow is designed according to the temperature difference of 4℃. The water flow rate in the pipe is designed according to 1~1.5m/s, and the fluctuation range of the cooling sea water temperature is -2~32℃. In order to ensure the normal operation of the system within the range of the sea water temperature change, an electric three-way adjustment is set between the inlet and outlet of the cooling sea water. Valve, in order to reduce vibration transmission and facilitate docking, hose connection should be used between the pipeline and the air conditioning interface.
◆Design of cooling sea water pipeline
The frame and leaking parts should be painted to prevent corrosion, and the electrical components should be made of anticorrosive materials and electromagnetic interference.