Luoyang HongtengIntermediate frequency induction furnace
Temperature Controller for Furnaces: On-Off vs Proportional Control A furnace temperature controller must do more than indicate temperature. It must convert the measured signal into an action that changes the heat supplied to the furnace. The following discussion explains early switching instruments, potentiometric control systems, and the mechanisms used to regulate fuel-fired and electric resistance furnaces. 1. Early On-Off Temperature Controllers A mercury switch provided one solution to the contact problems found in early control instruments. It consisted of a sealed glass tube containing gas and a small quantity of mercury. Two electrical leads were sealed into one end of the tube. Their material was selected so that it would not form an alloy with the mercury. A compliant depressor mechanism tilted the tube in response to the galvanometer mechanism. When the end containing the leads moved downward, the mercury bridged the leads and completed the circuit. Another design used a vane-operated controller without direct electrical switching contacts. A small, lightweight metal vane was attached to the instrument pointer and positioned between two fixed oscillator coils. Movement of the vane disturbed the oscillator circuit and caused a relay to operate. These instruments were suitable for on-off, or two-position, control where...
Temperature Controller for Industrial Furnaces: Thermocouples and Pyrometers A furnace temperature controller requires a measuring instrument that responds reliably to changes in temperature. Several physical effects can be used for this purpose: the expansion of solids, liquids or gases; changes in electrical resistance; and the electromotive force generated by two dissimilar conductors joined at a measuring junction. The radiation pyrometer described in the source also uses thermocouple elements, although these elements remain outside the furnace. Temperature Measurement Principles Each of these effects has been used for temperature measurement and control. The expansion of a solid, as employed in a bimetallic strip, is widely used for room-temperature control. Other effects have been incorporated into instruments suited to different furnace temperature ranges. Electronic amplification made small electrical signals easier to measure and increased the importance of two temperature-dependent effects in furnace instrumentation: changes in electrical resistance and changes in thermocouple electromotive force. These measurement methods were used before the discovery of the electron, and instruments based on them can operate without electronic amplification. Electronic instruments subsequently extended their measuring capabilities, particularly at low temperatures where the available signals are small. Thermocouples for Furnace Temperature Control The furnace control systems discussed in the...
Presenting full-line equipment for melting, casting, rolling and anti-corrosion, and deepening engagement with the Eurasian market From October 22 to 24, the 17th International Exhibition for Iron, Steel and Foundry, Non-Ferrous Metallurgy Technologies, Machinery and Products (ANKIROS 2026) was held at the Istanbul Expo Center in Türkiye. HTGP exhibited at Booth Hall 4 – E173, presenting a product portfolio that covers the full chain of melting, casting, rolling and steel pipe anti-corrosion. Over the three-day event the booth received more than a hundred batches of professional visitors from Türkiye and neighboring Eurasian countries. At this edition HTGP focused on five main equipment lines: induction melting furnaces for steel, aluminium and copper with high efficiency and stable temperature control; ingot casting machines for aluminium, copper and zinc ingots; foundry equipment for casting workshops; hot rolling mills for steel; and 3LPE steel pipe anti-corrosion equipment for oil and gas transmission. Equipment models, catalogues, technical data and project videos presented the machines on site, together with one-to-one selection advice based on each customer’s material type, capacity target and process flow. The ANKIROS 2026 venue and the HTGP booth Visitors were mainly local Turkish foundries and steel and non-ferrous metal processing enterprises, with others...
Luoyang Hongteng Electrical Equipment Co., Ltd. (HTGP) HTGP will participate in two major international exhibitions this October — FABEX Saudi Arabia 2026 in Riyadh and ANKIROS 2026 in Istanbul, Türkiye. We look forward to meeting customers and industry professionals, presenting selected equipment and components, sharing technical information and discussing project requirements face to face. FABEX Saudi Arabia 2026 Date: October 11–14, 2026 Venue: Riyadh International Convention & Exhibition Center, Saudi Arabia Booth: Hall 1 – A48 At FABEX Saudi Arabia 2026, visitors can meet our professional team, view selected HTGP equipment and components, review product catalogs and technical information, and watch real project videos. Our team will also be available for one-to-one discussions about equipment selection and specific project requirements. ANKIROS 2026 Date: October 22–24, 2026 Venue: IFM – Istanbul Expo Center, Türkiye Booth: Hall 4 – E173 At ANKIROS 2026, visitors can explore selected HTGP equipment and components, review technical specifications and product information, and communicate directly with our professional team. We welcome you to bring your project requirements and discuss suitable equipment solutions with us. HTGP at International Exhibitions HTGP regularly participates in international exhibitions to meet customers, exchange industry insights and communicate our metal hot processing...
Principles of Automatic Control In industrial furnaces, if high-quality products are to be produced, several physical and chemical variables must be kept essentially constant or controlled according to a preset program. These variables include temperature, pressure, gas composition, and, indirectly, flow rate. The basic principle of automatic control is the same for all of these variables, so it is useful to briefly explain the general principles before discussing each type of control. The variable to be controlled, such as temperature or pressure, is called the controlled variable. A variable that changes by itself and can influence the controlled variable is called an independent variable. In some processes, several independent variables may exist. Automatic control works as follows: a force is derived directly or indirectly from the controlled variable. This force is balanced by gravity, mechanical spring force, gas pressure, electromagnetic force, or another corresponding force. The element that produces the balancing force may take many different forms. When the independent variable changes, the value of the controlled variable also changes. This breaks the balance between the derived force and the opposing force. The small difference between these two forces causes a mechanism to move, attempting to return the controlled variable...
Metallurgical Principles of Heat Treatment The diagram shows a simplified equilibrium diagram for ordinary carbon steel. When the temperature is below 721°C, the normal structure of carbon steel containing 0.3% to 0.83% carbon is ferrite plus pearlite. Pearlite is a mixture composed of lamellar ferrite and cementite. When the temperature rises above 721°C, known as the Ac1 line, cementite begins to dissolve into the solid solution. When the temperature reaches the Ac3 line, the entire material transforms into austenite, which is a solid solution with a crystal structure completely different from the original ferrite. If the surface is rapidly cooled to about 350-200°C, the re-formation of the original ferrite and pearlite can be avoided, and the material passes directly through the martensitic stage. During this rapid cooling process, the crystals interlock with each other in a fine and hard crystal structure, forming very hard steel. This rapid cooling method is called quenching. For high-carbon steel with a carbon content of 0.8% to 1.7%, the amount of martensitic crystals increases, making the steel harder. This type of steel should not be heated all the way to the Acm line. Instead, it should be heated to a lower temperature, such as...
Induction Steel Melting Furnace
Aluminum Induction Melting Furnace
Stainless Steel Induction Melting Furnace
Medium Frequency Gold Induction Melting Furnace
Small Medium Frequency Induction Furnace
Aluminum/Copper Ingot Continuous Casting Line
Please fill out the form below (required *), send us a short message, and we will contact you as soon as possible.
Send Message
Copyright © 2026 Luoyang Hongteng Electrical Equipment Co., Ltd.
