Wuxi Wondery Industry Equipment Co., Ltd

I. Project Background and Equipment Application Positioning This case study involves a ladle heating station used for preheating ladle linings after repair and before receiving molten metal. The core function of the equipment is to provide smooth and controllable heating of the lining prior to casting, in order to stabilize the casting temperature regime, reduce metal loss, and ensure process repeatability. The operating environment is an industrial workshop, requiring stable operation across multiple heating cycles. The station is designed to accommodate a conical ladle with a 1-ton molten steel capacity. The ladle has an internal top diameter of 500 mm, internal bottom diameter of 410 mm, and depth of 900 mm; the external top diameter is 770 mm, and the overall height is 1,050 mm. These dimensions establish the geometric boundary conditions for heating element arrangement and station structural design – the conical inner cavity means the radial spacing of heating elements varies along the height direction, precluding the conventional arrangement used for equal-diameter cylindrical furnace chambers. II. Heating System Technical Parameter Requirements The equipment requires electric heating with a total installed power of no less than 30 kW. Heating elements are resistance type, required to withstand high-temperature long-term operation and cyclic thermal loading. The maximum heating temperature must be no less than 800°C, and the heating element temperature must exceed the lining working temperature to ensure sufficient heat transfer intensity without localized overheating. There are inherent constraints among these parameters: an 800°C lining target temperature means the heating element surface temperature must be maintained at a higher level to establish an effective radiative heat transfer differential. If the element surface load is set too high, heat transfer intensity increases but element life under cyclic thermal loading is shortened; if set too low, heating time is extended. Therefore, element material selection and surface load design constitute the core technical trade-off of this project. III. Temperature Uniformity and Control Accuracy Requirements The technical requirements specify two temperature indicators: system temperature stability control accuracy of at least ±10°C, and internal ladle temperature differential not exceeding 50°C. Uniform heating of the ladle inner surface is required along the full height, meaning the type and arrangement position of heating elements must be specifically selected in conjunction with the conical ladle geometry to minimize temperature gradients. The design challenge presented by the conical structure is that the lower section has a smaller diameter while the upper section has a larger diameter. If vertically suspended straight rod elements were used, the spacing between the lower section and the lining would be greater than at the upper section, resulting in insufficient radiative heat transfer intensity at the bottom. Therefore, elements may require segmented arrangement or non-standard geometry to compensate for this geometric difference. The control system must be capable of operating automatically according to a given heating curve, and also allow manual control of main parameters. Temperature control is achieved through real-time thermocouple monitoring, with real-time parameters displayed on the operation panel. Lining heating must be smooth and controllable, eliminating abrupt temperature changes – this requirement points to a heating rate limitation function, meaning the control system requires slope control capability rather than simple on-off temperature regulation. IV. Structural and Safety Design Requirements The heating unit must be insertable into the ladle interior and lockable in the working position. Heating elements must have protective structures to prevent mechanical damage and contact with the lining, such as heat-resistant steel protective mesh or protective sleeves. This requirement stems from actual operating conditions: during ladle lifting and positioning, positional deviation exists, and without protection, elements could be damaged by collision with the lining or ladle wall. Cable routing and connection points must be constructed from high-temperature-resistant materials suitable for high-temperature operation. The equipment structure must facilitate maintenance, allowing heating element replacement without complete disassembly – an important availability indicator, since heating elements are periodic consumables and replacement convenience directly affects equipment downtime. Safety requirements include short circuit, overload, and leakage protection devices, as well as emergency stop, over-temperature protection, and abnormal condition interlock protection functions. Hazardous areas must have structural guards to prevent accidental personnel entry. The equipment must be grounded per code, with no accessible live parts under normal operating conditions. Protection scope covers three risk categories: electric current injury, high-temperature injury, and injury from moving and rotating equipment parts. V. Environmental Adaptability and Power Supply Conditions The equipment is powered by AC 380V, 50Hz. The operating environment temperature range is +5°C to +40°C. The equipment structure must be resistant to dust, vibration, and other factors typical of metallurgical production conditions. This environmental requirement imposes constraints on the protection rating and cooling method of the electrical control cabinet – the dust and vibration environment of a metallurgical workshop is unsuitable for conventional open cooling structures. VI. Scope of Supply and Documentation Requirements The scope of supply includes the complete heating station, comprising heating elements, control cabinet, temperature measurement system, and connecting cables. Supply completeness must ensure the equipment can be directly commissioned without additional procurement of major components. Technical documentation includes operation manual, electrical schematic diagrams, general assembly drawings, and installation instructions, sufficient to ensure safe operation and maintenance of the equipment. VII. Service Life and Technical Support Requirements The warranty period is no less than 12 months from the date of commissioning. During the warranty period, faults and defects attributable to the manufacturer shall be rectified by the supplier. Under compliant operating conditions, equipment service life is no less than 5 years. The equipment must reach the set heating temperature within a reasonable process time agreed with the customer, and ensure parameter stability across multiple heating cycles for repeatable process operation. The control system must have high reliability and resistance to industrial interference. Technical support scope includes operational technical consultation, melting mode setup recommendations, and technical assistance under emergency conditions

I. Projekthintergrund und Ausrüstungsspezifikationen Bei dieser Fallstudie handelt es sich um einen vertikalen Schnelllöschöfen aus Aluminiumlegierung mit einer effektiven Arbeitsfläche von 1200×1200×1100 mm (Durchmesser × Höhe).Es handelt sich um einen zyklusbetriebenen Widerstandsheizofen, der hauptsächlich zur Lösungsabarbeitung und zum schnellen Ablösen von Aluminiumlegierungen und -platten verwendet wirdDie Ausrüstung hat eine Nennleistung von 135 kW, eine Nennspannung von 380 V, dreiphasige 50 Hz und eine Nenntemperatur von 650 °C mit einstellbarer Betriebstemperatur. Die Struktur dieser Geräte unterscheidet sich von den herkömmlichen Boxöfen: Die Werkstücke sind im Ofen aufgehängt.und der Löschbehälter befindet sich direkt unterhalb des Ofenkörpers. Nach dem Öffnen der Ofentür kann das Werkstück direkt ins Wasser fallen. II. Temperaturkontrolle und Zonierung Das Temperaturregelsystem verwendet eine zweistufige Architektur. Die obere Ebene ist ein 10-Zoll-Touchscreen, der für die zentralisierte Einstellung, Steuerung, Überwachung, Aufzeichnung,und Speicherung von WärmebehandlungsprozesskurvenDie untere Stufe verwendet Industrie-PID-Temperaturregler Eurotherm 3504 mit einer Steuergenauigkeit von ±1°C und einer Ofentemperaturuniformität von ±3°C während der Haltephase. Die Heizzonen sind als 2 in Sternkonfiguration miteinander verbundene Zonen konfiguriert.Schall- und SichtüberwärmealarmDie Temperaturregelung verfügt über eine Online-Selbstschaltfunktion, die optimale PID-Parameter anhand der tatsächlichen thermischen Eigenschaften des Ofen berechnet.Ausgleichsheizungsrate gegen Überschreitung. III. Konfiguration der Ofenbelagung und des Heizungselements Die Ofenverkleidung besteht aus refraktärer Baumwolle, wobei sowohl Wände als auch Dach aus Faserstrukturen mit einer Gesamtiddicke von mindestens 240 mm bestehen.Die Faser gefalteten Blöcke werden vor der Montage einer sekundären Vorkompression unterzogen, die eine Druckdichte von mindestens 230 kg/m3 erreichen und mit runden Balken aus rostfreiem Stahl an der Ofendecke befestigt sind.,Die Befestigungskomponenten sind aus 1Cr18Ni9Ti-Edelstahlplatte gestempelt. Die Wärmeelemente bestehen aus 0Cr25Al5-Legierungsstreifen, die mit speziellen Formen gepresst werden, um Verarbeitungsschäden zu vermeiden.die eine bequeme und schnelle Wartung und den Austausch ermöglichen. Während der Montage werden keramische Wäscher zwischen die Faserwand und den Widerstandsstreifen platziert, um einen direkten Kontakt zwischen der Faseroberfläche und dem Streifen zu verhindern,Auf diese Weise wird die Wärmeabgabe aus dem Streifen erhöhtSowohl Keramikschrauben als auch Waschmaschinen sind aus hochhaltigem Aluminiummaterial hergestellt und bei hohen Temperaturen gesintert, um eine ausreichende Festigkeit und Lebensdauer zu gewährleisten.Die Widerstandsstreifen sind um die Ofenkammer hängenDie Heizungselemente verwenden eine Sternverbindung, wobei die Oberflächenbelastung unter 1 gesteuert wird.6 W/cm2 ¢ ein Wert unter dem herkömmlichen Konstruktionsgrenzwert für Widerstandsstreifen, die zur Verlängerung der Lebensdauer eines Bauteils unter häufigen Heiz- und Kühlzyklen bestimmt sind. IV. Warmluftzirkulation und Luftführungssystem Auf dem Ofendach ist ein hochtemperaturbeständiger Kreislaufventilator mit einer Leistung von 7,5 kW installiert.mit Luftkühllagern für die hochtemperaturförmige DachumgebungDie Luftleitkappe maximiert die Längskomponente der vom Lüfter erzeugten Zentrifugalkraft und drückt heiße Luft nach unten.Die Luft umgeht dann das Werkstück und wird von unten wieder in den Lüfteranschluss gezogen, die einen geschlossenen Kreislauf bilden.Dieser Luftströmungspfad sorgt für die Gleichmäßigkeit des Temperaturfeldes innerhalb der Ofenkammer und ist ein Stützkonzept für die Aufhängungslastmethode, wodurch der Luftstrom durchläuft. V. Materialkorbheben und Öffnungstürverriegelungsmechanismus Der Materialkorbhebenmechanismus besteht aus einer elektrischen Winde, einer Ringhebekette und Katzenscheibenblöcken.Die Winde ist eine elektrisch gesteuerte Einheit mit zwei Geschwindigkeiten mit einer Seilgeschwindigkeit von bis zu 18 Metern pro Minute, die den Anspruch auf einen schnellen Abstieg in das Wasser erfüllt; die Aufstiegsphase verwendet eine langsame Geschwindigkeit, um den Trägheitsschlag zu verringern, wenn das Werkstück und der Korb in den Ofen gelangen.Die Winde verfügt über Inching-Steuerung und eine SelbstverschlussvorrichtungDie Schrägsteine werden mit einer 16Mn-Ringkette ausgerüstet, um den hochtemperaturspezifischen Öfen zu dienen.mit einer Breite von mehr als 30 mm,, um ein reibungsloses Heben und Senken des Korbs zu gewährleisten. Die Öffnung und Schließung der Tür wird durch einen Zylinder angetrieben.Bei Schließung, drückt der Zylinder die Tür in die geschlossene Position und setzt den Druck fort, indem er die Tür über einen Hebel an der Seite nach oben hebt, um sie fest gegen den Ofenkörper zu drücken.Der Hebemechanismus und der Ofentürmechanismus sind miteinander verbunden: Der Aufzugsmechanismus kann erst eingeschaltet und betrieben werden, wenn die Ofentür vollständig geöffnet ist (wenn dann die Stromversorgung des Heizteils abgeschaltet ist).Diese Verriegelungslogik verhindert, dass die Ausrüstung beschädigt wird, wenn die Tür nicht geöffnet ist. VI. Übertragungszeit und Auslöschbehälter Die Übertragungszeit für das Löschen ist definiert als die Zeit von der Öffnung der Ofentür bis zum vollständigen Eintauchen des Werkstücks in Wasser, wobei die Konstruktionsanforderung nicht mehr als 10 Sekunden beträgt.Dieser Parameter ist für den Aluminiumlegierungslösungsbehandlungsprozess von entscheidender Bedeutung., je höher die Kühlgeschwindigkeit durch den löschempfindlichen Bereich und desto besser die Alterungserstärkung. Der Löschbehälter ist von mobiler Konstruktion und wird von einem Motor mit 2,2 kW angetrieben.Aufrechterhaltung einer gleichmäßigen Wassertemperatur und Beschleunigung der Wärmeübertragung von der WerkstückoberflächeDer Tank ist aus 5 mm dickem Stahlblech geschweißt und auf Leckdichtigkeit geprüft.mit dem vorderen Teil als Werktabelle und dem hinteren Teil als Wasserbehälter, mit drei Rädern (ein Antriebsrad). VII. Abfolge der Prozessmaßnahmen Die komplette Aktionsfolge der Ausrüstung ist wie folgt: manual loading → quenching cart moves to below the furnace body → furnace door opens → material frame lifting mechanism descends → manual hooking → material frame rises → furnace door closes → heating and holding according to process time → solution treatment ends → stirring water pump starts → furnace door opens → material frame descends → material frame rapidly enters water for quenching → material frame rises → quenching cart exits → material frame descends → manual unhooking followed by return to furnace opening → furnace door closes → manual unloading → next cycle begins.

I. Project Background and Equipment Specifications This case study involves a medium frequency induction melting furnace, model WDL-KGPS-500, with a rated capacity of 0.5 tons and a maximum capacity of 0.6 tons, designed for aluminum melting applications. The equipment employs medium frequency induction heating and is equipped with a hydraulic tilting system for molten aluminum discharge. The most notable configuration feature of this equipment is its grid compatibility scheme: the power supply side is fed at 440V/3P/60Hz, while the medium frequency power supply input voltage is specified at 380V. This means the equipment is intended for 60Hz grid regions (such as South Korea, parts of Central and South America, and the Middle East), requiring a transformer or voltage adaptation unit either inside or external to the power supply cabinet to step down the 440V grid voltage to 380V before feeding the medium frequency power supply. This dual adaptation of both voltage and frequency is a parameter that must be confirmed upfront during the electrical design phase for export projects. II. KGPS Medium Frequency Power Supply System The power supply system adopts the KGPS thyristor-based medium frequency power supply, with a rated power of 400 kW, a medium frequency output voltage of 2400 volts, and an output frequency of 1000 Hz. The power factor exceeds 0.9, and the startup success rate is 100%. The rectifier section is a three-phase full-controlled bridge with a three-phase six-pulse rectifier structure and a parallel-connected inverter. The control circuit employs an eighth-generation digital circuit board architecture, featuring wide frequency range adaptability, constant power control, swept-frequency zero-pressure soft start, and dual closed-loop voltage-current feedback. The swept-frequency zero-pressure startup means the system automatically scans frequencies during startup, establishing medium frequency oscillation upon finding the load resonant point – avoiding the sensitivity to load parameter variations inherent in separate-excitation startup methods. The protection system encompasses overcurrent, overvoltage, undercurrent, undervoltage, water loss, and phase-loss conditions. When any protection parameter exceeds the set threshold, the system automatically blocks pulse output and disconnects the main circuit power. The power supply cabinet panel includes full voltage, current, and power readings along with operating status indicators. The capacitor cabinet provides medium frequency parallel compensation, reducing reactive power transmission losses on the distribution lines. The capacitor bank capacity is matched to the resonant frequency of the induction coil, ensuring operation near the resonant point under rated conditions. III. Induction Coil Design and Magnetic Yoke Shielding The induction coil is the core energy conversion component, constructed from T2/TU1 copper with a wall thickness of 4 mm. When energized, the coil generates a 1000 Hz alternating magnetic field that induces eddy currents in the metal charge within the furnace hearth, generating heat. The coil design is based on electromagnetic field principles and verified through dedicated computer software, with the deviation between actual operating power and design power controlled within 5%. Turn-to-turn insulation is processed using advanced insulation techniques, with dedicated clamping technology reducing axial vibration of the coil. The coil inner wall is sprayed with imported high-temperature-resistant insulating materials, and a furnace lining leakage alarm system is installed – when molten aluminum seeps into the coil layer, the system detects it early and signals the condition, preventing furnace breakout incidents. A refractory coating of 10 to 15 mm thickness is applied to the inner surface of the coil, serving both to facilitate furnace lining construction and to prevent thermal deformation of the lining. The magnetic yokes are of crescent profile construction, laminated from cold-rolled silicon steel sheets and clamped with stainless steel splints. The contact surface between the yoke and the coil outer surface is curved, providing face contact rather than line contact, achieving better clamping efficiency and reduced magnetic flux leakage. The silicon steel sheets are reinforced with dedicated splints rather than through-bolts, maximizing the effective magnetic area and reducing localized heating. The magnetic yokes simultaneously shield magnetic flux leakage, prevent furnace body heating, and support and secure the induction coil. IV. Hydraulic Tilting System Furnace tilting is driven by a hydraulic system with two cylinders arranged on both sides of the furnace body for lifting, with furnace return accomplished by gravity. The hydraulic station is equipped with dual motors and dual pumps – one in service and one on standby, with automatic switching capability. The fuel tank is fully enclosed and welded to prevent hydraulic oil leakage. The tilting angle range is 0 to 95 degrees, with smooth operation without shock or creeping, adjustable speed, and the ability to hold at any position. Tilt operation is controlled via manual valves, suitable for casting processes requiring precise control of molten aluminum pouring volume. V. Crucible Mold and Lining Formation A configuration detail of this equipment is that it supplies a crucible mold rather than a finished graphite crucible. The crucible mold is formed from 3 mm iron plate and is used to control the shape and volume positioning of the refractory lining during formation. The user must select the lining material and ramming/sintering method according to the specific metal being melted and the casting process – a difference at the user operation level compared to solutions that directly supply finished graphite crucibles. The positioning function of the crucible mold ensures dimensional consistency of the lining cavity, thereby maintaining the coupling distance between the furnace hearth and the induction coil stable within the design range. VI. Water Cooling System and Cooling Cables The water-cooled cables are constructed from TU1 multi-strand oxygen-free copper wire, sheathed in high-strength fire-resistant rubber tubing, with cold-formed connectors ensuring contact resistance and tensile strength. The power supply side requires a cooling water flow rate of no less than 8 m³/h, while the furnace body side requires no less than 12 m³/h. The outlet water temperature on the power supply side must not exceed 35°C, and on the furnace body side must not exceed 45°C, with inlet water pressure maintained between 0.15 and 0.35 MPa. The water cooling system employs a fully enclosed circulating cooling method using soft water as the circulating medium. The core advantage of soft water circulation lies in avoiding overheating damage to the power supply, thyristors, capacitors, IGBT modules, and induction coil caused by scale deposition; additionally, soft water contains no ionic conductive components, so cooling components will not be damaged by electrolysis. The system requires no water pool or cooling tower, occupies minimal floor space, and has low makeup water consumption. The cooling system consists of three parts: main machine, water tank, and control box. The main machine includes the housing, copper cooler, exhaust system, spray system, water separator, collecting annulus, and spray pump. The water tank includes the main pump (one in service, one standby), stainless steel water tank, electrical cabinet, temperature control system, and pressure control system. The control box enables remote operation of the water cooling system, displaying water temperature and allowing setup of delayed operation after work hours.