In the disassembly and assembly of large bolts in power, chemical, petroleum, heavy machinery and other industries, slow bolt heating and inconsistent temperature rise among bolts of the same batch are often encountered on site, resulting in reduced efficiency. The BRJ-220 bolt electric heating rod addresses this issue through parameter matching and structural design.
The heating rod consists of a high-temperature alloy heating wire, a magnesium oxide insulation layer, a stainless steel sheath and lead wires. The end can be equipped with plugs or terminals of different specifications according to the diameter of the bolt center hole. The outer diameter and length of the heating rod are customized to the size of the bolt center hole, ensuring a uniform gap with the hole wall after insertion to reduce local overheating. The conventional adaptable hole diameter range is 8 mm to 30 mm, and the length covers 50 mm to 500 mm.
The BRJ-220 has a rated voltage of 220V, and a 380V version can also be provided according to on-site power supply conditions. The power of a single rod is selectable between 0.5kW and 3kW, and the power density is controlled within a reasonable range to avoid excessive surface load affecting service life. The insulation resistance is not less than 50MΩ in cold state, and the withstand voltage test is carried out according to relevant standards. The lead wires use high-temperature resistant conductors, and the length can be adjusted according to the position of the control cabinet.
The heating rod is usually used with the ZJK series control cabinet, and the heating power is adjusted by voltage regulation or on-off control. The voltage adjustment indicator of the control cabinet should be set to the minimum position before starting. The WQJ low-voltage control cabinet must not be shifted under load to prevent contact arcing or equipment damage. During use, ensure that the bolt hole is clean and free of oil stains, power on only after the heating rod is fully inserted, and avoid prolonged no-load heating.
When purchasing, the bolt center hole diameter, hole depth, required heating temperature and heating time must be specified to determine the diameter, length and power of the heating rod. For bolts of different specifications, it is recommended to configure corresponding models of heating rods separately and not to mix them. In addition, attention should be paid to whether the supplier provides material certificates and electrical performance test reports to ensure that the product meets the relevant standard requirements of the Ministry of Machine Building and Electronics Industry.
