RJ-17.5-950 Bolt Heater + Control Cabinet: High-Efficiency and Safe Heating in Power Plants

In power plants, numerous large bolts are found on turbines and boilers. Dismantling or installing these bolts requires preheating—thermal expansion and contraction loosen the bolts, making them easy to turn. However, the heating process is complex: bolts of different materials and sizes require different amounts of heat; power plants have strict electricity management protocols to prevent trips and leakage; and the fast pace of operations means no delays are tolerable. Conventional bolt heaters, either with fixed voltage or lacking a dedicated control system, often fail to meet these demands.

The RJ-17.5-950 Bolt Heater, paired with its specialized DC Variable Control Cabinet, offers a stable, adjustable voltage range of 0 to 220V, along with superior safety and controllability, precisely addressing the pain points of power plant operations. Below, we detail how this solution helps power plants solve their electricity and operational challenges.

Precisely Matching the Heating Needs of Different Bolts

Power plant bolts are not “one-size-fits-all.” Turbine casing bolts are thick and require substantial heat, while pipe flange bolts are thinner and can easily warp from excessive heat. A conventional bolt heater with a fixed voltage, such as 220V, might be too slow for thick bolts or cause overheating in thin bolts—either delaying work or damaging the bolts.

The RJ-17.5-950 Bolt Heater, with its control cabinet, allows the voltage to be smoothly adjusted from 0 to 220V. Increase the voltage for fast heating, or decrease it for steady heating. For example, when dismantling a thick bolt, the voltage can be set to 180V for a rapid initial temperature rise, then slightly lowered to maintain the temperature once the bolt is heated through. When installing a thin bolt, the voltage can be set to only 100V for gradual heating, preventing uneven thermal stress that could lead to cracking.

There is no longer a need to purchase different heaters for different bolts; one RJ-17.5-950 system is sufficient. Many power plants previously had to stock three or four types of heaters for bolt replacement; now, they use only this single model, reducing inventory and simplifying operations. If your power plant is still struggling to select heaters for different bolts, please contact us to see if this variable-voltage solution is suitable for your bolt types.

Safety Design: Compliant with Power Plant’s Strict Electrical Management

Electricity use in a power plant is a “high-voltage line”—leakage can cause injury, and overload can trigger a trip, affecting the entire unit’s operation. The RJ-17.5-950 and control cabinet solution is fully optimized for safety.

The control cabinet includes overload protection. If the heater accidentally short-circuits against a metal casing, or if the voltage is set too high, causing an overcurrent, the control cabinet immediately cuts power, preventing wire burnout and trips that would affect other equipment. It also features leakage protection. The heater’s cable has double-layer insulation, and even if the outer layer is damaged, the inner layer maintains current containment. If the control cabinet detects leakage, it immediately shuts down, preventing electric shock.

Unlike some ordinary bolt heaters without protection devices, which trip the breaker upon a short circuit, shutting down the entire work area for an extended recovery time, this system’s safety design perfectly aligns with the power plant’s “zero safety incident” electrical management requirements. If your power plant has experienced issues due to heater leakage or overload, switching to this solution can prevent numerous problems. For safety concerns, please contact us for a detailed safety assessment.

Stable Output: Reducing Work Interruption

Power plant operations emphasize a “single-run” approach. If the voltage suddenly fluctuates halfway through heating a bolt for dismantling, the temperature drops, the bolt tightens again, and reheating is necessary—taking far too long to complete a single task.

The control cabinet for the RJ-17.5-950 Bolt Heater provides stable voltage output. Regardless of minor fluctuations in the power grid voltage (e.g., a slight dip caused by other equipment starting), the control cabinet maintains a steady output voltage. The heater temperature remains stable, ensuring the bolt is heated evenly. When dismantling, the bolt can be loosened in one attempt without repeated heating.

For instance, one power plant previously used ordinary heaters, and during turbine bolt removal, a grid fluctuation would cause the heater temperature to drop. Bolts that should have taken 1 hour to remove ended up taking 2 hours. After switching to the RJ-17.5-950 and control cabinet, the voltage remained steady, and bolt removal time was halved, significantly improving operational efficiency. If your power plant frequently experiences delays due to unstable heating, this system can help reduce interruptions. Contact us to discuss specific scenarios for efficiency improvement.

Centralized Control: Minimizing Unnecessary Trips

Bolt heating in a power plant often involves multiple simultaneous locations—such as bolts on both sides of the turbine or several boiler flanges. Ordinary heaters require manual monitoring and adjustment at each point, leading to excessive movement and the risk of incorrect parameter settings.

This solution supports centralized control. A single control cabinet can be connected to several RJ-17.5-950 bolt heaters, allowing the operator to view the voltage and temperature of each unit and remotely adjust parameters from the control room. There’s no need to travel between various work points; all heaters can be managed from a central location.

For example, during a major overhaul requiring simultaneous heating of 6 bolts, 3 people were previously needed to monitor them individually. Now, 1 person in the control room can handle it, cutting labor in half. Furthermore, parameters are digitally displayed, eliminating the possibility of recording errors and ensuring clear management. If your power plant has numerous heating points and complex management, the centralized control feature can significantly save manpower. Contact us for a system setup proposal.

Practical Application: An “Indispensable Helper” During Major Overhauls

Major overhauls are the busiest times for power plants, with a large volume of bolts to be disassembled and assembled, requiring a balance between electricity management and efficiency. The RJ-17.5-950 and control cabinet solution is particularly effective during this period.

For example, when dismantling the main boiler flange bolts, which are thick and require a large amount of heat, the control cabinet voltage can be set to 200V for stable heating for 20 minutes. Once heated through, the bolts can be easily removed. During assembly, the voltage is set to 120V for slow heating, ensuring the bolt is evenly heated. The torque applied during tightening is accurate, preventing poor sealing caused by uneven heating.

Moreover, with numerous electrical devices running during an overhaul, the control cabinet’s safety protection prevents safety incidents, and centralized control reduces manpower—ensuring smooth, organized work and timely completion of the overhaul schedule. Many power plants report after their major overhauls that this bolt heating solution is far superior, offering peace of mind and high efficiency.

The RJ-17.5-950 Bolt Heater paired with the DC Variable Control Cabinet is designed entirely around power plant needs, from adjustable voltage and safety stability to centralized control. Whether your concern is strict electrical management or improving operational efficiency, this solution is a perfect fit.

If your power plant encounters issues with voltage adjustment, safety concerns, or complex management during bolt heating, or if you wish to procure the RJ-17.5-950 bolt heater and its dedicated control cabinet, please contact us. We provide not only genuine equipment, but also a professional team to help you develop a customized heating solution based on your bolt types and operational scenarios, making your power plant’s bolt heating work both safe and highly efficient.

E-mail: sales@yoyik.com
Tel: +86-838-2226655
Whatsapp: +86-13618105229

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