Bolt electric heating rods are specialized electric heating tools used in industrial fields (especially steam turbines, pressure vessels, pipeline flanges, etc.) for the installation and removal of large bolts. The core principle is to heat the central hole of the bolt to cause thermal expansion, thereby easily completing the installation and removal work. Combined with your procurement needs, the following are the core selection points and local manufacturer references for bolt electric heating rods:
Core Selection Parameters
When selecting, the following parameters need to be matched with priority to ensure adaptation to on-site working conditions:
Size Specifications: Selection should be based on the central hole diameter of the bolt to be heated. The conventional product central hole diameter adaptation range is 10-36mm, the protective sleeve length is 200-2000mm, and the heating length is 100-1700mm. Customization is possible according to the actual bolt length.
Electrical Parameters: The rated voltage supports 220V±20V, DC 100V, or low voltage 50V. The power range is 300-20000W. The surface power density is strictly controlled at 8-11W/cm² to ensure uniform heating without local overheating.
Material Requirements: The heating wire uses 0Cr27A17Mo2 high-resistance electric heating alloy wire (working temperature 400°C). The protective sleeve is a 1Cr18Ni9Ti heat-resistant stainless steel tube. The insulation material is standard-compliant dried magnesium oxide powder, meeting the long-term operation needs of industrial high-temperature and dusty environments.
Safety Standards: Cold-state insulation resistance ≥50MΩ. Withstand voltage test 1500-2000V/1min without breakdown. Hot-state leakage current not greater than 0.5mA per kilowatt. Cumulative service life not less than 50 hours. The shell must be equipped with a good grounding device.
Local and Surrounding Manufacturer References
Jiangsu is the core industrial belt for electric heating equipment in China. Yangzhou and its surrounding areas have many manufacturers specializing in the production of bolt heating rods, making on-site inspections and after-sales coordination convenient:
Yangzhou Local: Baoying County Hengtai Electrical Equipment Factory and Yangzhou Huaneng Electric Heating Technology Co., Ltd. are both located in Baoying County, Yangzhou. They have long supplied bolt electric heating rods, support non-standard customization, and can be used with DC adjustable control cabinets.
Surrounding Areas: Zhenjiang and Yangzhong also have many professional electric heater enterprises, such as Zhenjiang Yunlong Electric Appliance and Zhenjiang Huyang Electric Appliance, etc. They have been deeply engaged in the electric heating field for decades, with products covering multiple industries such as electric power and chemical engineering, and can provide complete heating solutions.
Selection Precautions
Prioritize confirming parameters such as the central hole diameter, length, and material of the on-site bolts to avoid low heating efficiency or bolt damage caused by size mismatch.
If used in special working conditions such as power plants and petrochemicals, products with explosion-proof certification and compliance with electric power industry standards should be selected. Some high-requirement scenarios can be equipped with intelligent temperature control cabinets to achieve precise temperature control.
During procurement, manufacturers can be asked to provide inspection reports such as insulation resistance and withstand voltage tests for the products to ensure compliance with safety standards.
