According to GB/T 151 "Heat Exchangers" and JB/T 4736 related requirements, the heat transfer performance of the heat pipe heat exchanger is based on the medium temperature, corrosiveness, and fin-side working conditions. For on-site technical engineers, the following precautions are listed item by item according to maintenance actions, for reference during inspection and repair.
During on-site operation and maintenance, the matching pipe material and fin spacing should be selected based on the type of tank liquid and working temperature. If the medium is replaced or the process temperature is adjusted, the original selection record must be rechecked to confirm that the temperature and corrosion resistance grade of the pipe material and the fin spacing are still applicable; for the flue gas side containing dust or prone to scaling, a larger spacing should be used and the ash cleaning cycle shortened.
The three parameters to be confirmed during selection: the first is medium corrosiveness, which determines the choice of pipe material and weld material; the second is working temperature and fluctuation range, which affects the verification of heat pipe working fluid and pipe wall temperature; the third is allowable pressure drop and installation space, which relates to fin spacing and structural arrangement.
When used in an environment with combustible gas, the wiring cavity can use an explosion-proof structure, and a temperature controller can be built in as needed. During maintenance, verify that the explosion-proof grade marking is consistent with the nameplate, and check whether the temperature control loop setting value is within the process allowable range, to avoid overtemperature caused by contact adhesion or sensor deviation.
Inspection focuses include: dust accumulation and corrosion signs on the fin surface, leakage at the connection between pipe ends and tube sheet, whether the heat pipe inclination angle has shifted, and whether the insulation layer is damaged. When a single heat pipe fails, it is advisable to record its position and evaluate the overall heat exchange margin of the unit; it should not be operated with the fault for a long time.
During shutdown, drain the accumulated liquid, keep it dry and ventilated, and apply anti-rust treatment to exposed metal parts; before restarting, first perform air tightness and insulation checks, then slowly put it into operation according to the heating curve.
