During on-site use of bolt electric heating rods, common problems include: improper selection of heating position, directly heating the threaded and nut sections, leading to thread galling and fastening failure; the temperature of the center hole wall exceeding the maximum service temperature of the bolt, causing degradation of material properties; and safety hazards caused by low insulation resistance and excessive leakage current. To address the above problems, the SRB-380 bolt electric heating rod provides solutions from three aspects: structural design, parameter control, and application specifications.
This model adopts a single-end lead-out wiring method, suitable for bolts with limited center hole depth. The rated voltage is AC 220V, with an allowable fluctuation range of ±20V, and DC 100V power supply can also be selected according to working conditions. When the heating rod is energized in air at the rated working voltage for 2 to 3 minutes, no overheating phenomenon shall occur, the insulation resistance shall not be less than 0.5MΩ, and the leakage current shall not exceed 0.5mA per kilowatt. For bolts of M36 and above, models with double-end lead-out or with a K-type thermocouple can be selected to achieve closed-loop temperature regulation and control the center hole wall temperature within the allowable range of the bolt material.
The heating position should be the threaded rod section, avoiding direct heating of the threaded and nut sections. Before installation, the inner wall of the center hole should be cleaned to ensure that the heating rod is inserted in place and the gap with the hole wall is uniform. The energization heating time should be adjusted according to the bolt specifications and ambient temperature, and generally a single heating session should not exceed 5 minutes. For occasions requiring precise temperature control, it is recommended to use it together with a thermocouple and a temperature control box, and the temperature control box should have over-temperature alarm and automatic power-off functions.
The SRB-380 bolt electric heating rod is suitable for flange bolt tightening and disassembly operations in industries such as electric power, petrochemical, and metallurgy, and is especially suitable for occasions with narrow spaces where flame heating is inconvenient. When selecting, procurement personnel need to confirm the bolt specifications, center hole diameter and depth, power supply voltage, and whether temperature feedback is required. For bolts of M36 and above, it is recommended to choose models with a K-type thermocouple to achieve closed-loop temperature regulation.
