To ensure the safe operation of the cold room refrigeration equipment, not only the correct design of the cold storage, the correct material selection, careful manufacturing, and strict inspection but also the perfect safety and testing equipment must be available.
1) It is required that the quality and mechanical firmness of all manufacturing materials of cold room refrigeration equipment must meet the general standards of mechanical manufacturing. The mechanical materials contacting ammonia and lubricating oil shall be stable to ammonia and lubricating oil in chemical properties, and shall be able to withstand the changes of different temperatures and pressures in operation.
2) A spring safety valve shall be installed between the suction side and the exhaust side of the compressor. Generally, it is stipulated that when the pressure difference between the inlet and outlet exceeds 1.4mpa, the compressor shall be started automatically (the pressure difference between the low pressure of the two-stage compressor and the inlet and outlet of the compressor is 0.6MPa), so that the high-pressure ammonia gas returns to the low-pressure chamber, and no stop valve shall be installed between its channels.
3) The cylinder of the ammonia compressor is provided with a safe airflow with a buffer spring. When the pressure in the cylinder exceeds the exhaust pressure by 0.2 ~ 0.35Mpa (gauge pressure), the safety cover will open automatically.
4) The condenser, liquid reservoir (including high and low-pressure liquid reservoir, drain drum), intercooler and other equipment shall be equipped with a spring safety valve. Its opening pressure is usually 1.85mpa for high-pressure equipment and 1.25mpa for low-pressure equipment. The stop valve shall be installed in front of the safety valve of each equipment, which shall be in the open state and lead seal.
5) The ammonia storage container installed outdoors shall be covered with a canopy to prevent sunlight.
6) The suction and discharge sides of the compressor shall be equipped with a pressure gauge and thermometer. The pressure gauge shall be installed between the cylinder and the shut-off valve, and shall be equipped with a control valve; the thermometer shall be hard equipped with a sleeve, which shall be set within 400mm before or after the stop valve depending on the flow direction, and the end of the sleeve shall be inserted into the center of the pipe.
7) Two entrances and exits shall be reserved in the machine room and equipment room to ensure safety, and the standby main switch (emergency switch) of the compressor power supply shall be installed near the exit, and it is only allowed to be used in case of an emergency shutdown.
8) The machine room and equipment room shall be equipped with a ventilation device to prevent accidents. Its function requires that the indoor air be changed 7 times per hour. The starting switch of the device shall be equipped indoors and outdoors.
9) To prevent accidents (such as fire) without an explosion of the ammonia storage vessel, an emergency ammonia leakage device shall be installed in the refrigeration system. In case of crisis, the ammonia in the vessel shall be discharged through the sewer.