1、 Start up operation and precautions
(1) When used on the new process pipeline, pay attention to eliminate the sundries in the pipeline to avoid blocking the heat exchanger.
(2) If sewage is used as the cooling medium, or the waste heat of sewage is recovered, or the medium contains granular solids, a filter or decontaminator shall be installed at the inlet end of the heat exchanger to avoid blocking the heat exchanger.
(3) When the temperature of cooling water (heated) exceeds 40 ℃, softening treatment shall be carried out as far as possible to avoid scaling of heat exchanger and affecting heat transfer effect.
(4) Check whether the pipeline connection is correct to avoid mixing the two media and causing adverse consequences.
(5) Before start-up, strictly check whether the inlet valves of cold and hot media are closed and whether the outlet valves are open.
(6) Start up after completing the above work. Start the pump of cold and hot medium first, slowly open the inlet valve of cold medium, and then open the inlet valve of hot medium to make the medium slowly flow into the heat exchanger to avoid excessive temperature.
(7) Check all sealing surfaces and all welds for abnormal phenomena such as leakage.
(8) Slowly raise the temperature, and measure and calculate whether it meets the process requirements. Normal operation can be started after meeting the requirements.
2、 Normal operation and inspection
(1) Regularly check all sealing surfaces and welds of the heat exchanger to see if there are abnormal phenomena such as leakage. If leakage is found, mark the leakage in time and deal with it after shutdown.
(2) Check the pressure gauge and thermometer regularly to see if there is any abnormality.
(3) When stopping, first slowly close the inlet valves of hot and cold media, and then close the outlet valves of the two media. On the contrary, open the outlet valve first, and then slowly open the inlet valve.
(4) The medium on the low-pressure side shall be tested regularly to avoid mixing with the medium on the high-pressure side. If there is any mixing, it indicates that there is internal leakage and it should be shut down for treatment.
3、 Shutdown operation and precautions
(1) Before shutdown, the pump must be stopped and the power supply must be cut off.
(2) After stopping the pump, first slowly close the inlet valve of hot medium, and then close the inlet valve of cold medium. Finally, close the outlet valves of the two media.
(3) If a vent valve is installed on the pipeline, it shall be opened.
(4) For the medium with high temperature and corrosive medium, the equipment shall be vented as far as possible to avoid scalding and corroding the equipment when opening the equipment.