The electric thermal oil heater (also known as the electric heating thermal oil furnace) is a closed-loop liquid-phase industrial heating device that uses electricity as the heat source and thermal oil as the heat carrier. It consists of six core systems in total, with the specific structural composition as follows:
First, the heating body system. As the core unit of electric-to-thermal conversion, it includes a pressurized furnace body, an electric heating tube assembly, and an insulation shell. The furnace body is manufactured according to pressure vessel standards, serving as a carbon steel or stainless steel sealed cavity with internal flow guidance structures to ensure uniform heat exchange for the oil flow. Immersed electric heating tubes are fixed to the furnace body via flanges, containing nickel-chromium resistance wires and magnesium oxide insulation fillers, while the outer shell is made of high-temperature-resistant stainless steel, with strictly controlled surface power density to prevent thermal oil coking. The outer layer of the furnace body is wrapped with aluminum silicate insulation cotton, and an additional metal protective shell is installed to reduce heat loss.
Second, the hot oil circulation system. It drives the heat transfer oil to flow forcibly in a closed-loop circuit for heat exchange, with the core component being a specialized circulating pump for high-temperature-resistant heat transfer oil, which provides stable flow and head to the system, delivering the high-temperature oil to heating equipment and returning it after cooling for reheating. The piping is connected in series with an oil filter to remove impurities and carbonized substances from the oil, protecting the pump body and heating tubes. Supporting pipelines and a group of valves, including shut-off valves and check valves, control the oil flow path and prevent backflow of the oil.
Third, the expansion oil storage system. It compensates for the volume changes of the heat-conducting oil due to thermal expansion and contraction, balancing system pressure. The core component is the high-positioned expansion tank, connected to the main system via an expansion pipe, which accommodates the incremental volume of the heat-conducting oil during thermal expansion. It also serves functions such as oil replenishment, gas venting, and pressure stabilization. A level gauge is installed for real-time monitoring of the oil level, while oil replenishment ports and overflow ports ensure stable oil levels, simultaneously expelling air and light component gases from the system to prevent gas resistance affecting circulation.
Fourth, the temperature control system. It enables precise oil temperature regulation by installing temperature sensors at the heater inlet and outlet as well as the heating terminal to collect real-time oil temperature signals. Standard PID digital temperature control instruments are equipped to adjust heating power via contactors or solid-state relays, achieving a conventional temperature control accuracy of ±1°C. High-end models can be configured with PLC touch screens, supporting multi-stage programmed temperature control and remote data communication.
Fifth, the safety protection system. It features multiple safeguard mechanisms, including an independent overtemperature alarm device that automatically cuts off the heating power when the oil temperature exceeds the safety threshold. The pressure gauge and pressure relay monitor system pressure, triggering alarms or pressure relief in case of anomalies. Low-level protection triggers shutdown to prevent dry burning and damage to heating tubes. The base model is equipped with electrical protections such as overload, short circuit, and phase loss, while the explosion-proof type additionally includes flameproof electrical control components, suitable for flammable and explosive working conditions.
Sixth, auxiliary supporting components. The integrated electrical control cabinet houses all control and protection elements; the skid-mounted frame carries all components, and the system can be put into operation by connecting the pipelines and power supply. A drain valve is installed at the bottom of the furnace body, and an air vent is set at the highest point of the system for daily operation and maintenance. Some models can be optionally equipped with a cooling heat exchanger to achieve rapid oil temperature reduction.
If you want to know more about our product, please contact us!
Post time: Aug-06-2026
