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. Latar belakang proyek dan spesifikasi peralatan Studi kasus ini melibatkan tungku pemadam cepat paduan aluminium vertikal dengan zona kerja efektif 1200×1200×1100 mm (diameter × tinggi).Ini adalah tungku pemanasan resistansi yang dioperasikan siklus terutama digunakan untuk pengolahan larutan dan cepat meredakan castings paduan aluminium dan pelatPeralatan ini memiliki daya nominal 135 kW, tegangan nominal 380V tiga fase 50Hz, dan suhu nominal 650 °C dengan suhu operasi yang dapat disesuaikan. Posisi struktur peralatan ini berbeda dari tungku pemadam kotak konvensional: benda kerja digantung di dalam tungku,dan tangki pemadam terletak tepat di bawah tubuh tungkuSetelah pintu tungku dibuka, benda kerja dapat jatuh langsung ke dalam air ∙ tata letak vertikal ini adalah dasar fisik untuk mencapai transfer cepat. II. Kontrol suhu dan desain zonasi Sistem kontrol suhu menggunakan arsitektur dua tingkat. tingkat atas adalah layar sentuh 10 inci yang bertanggung jawab untuk pengaturan terpusat, kontrol, pemantauan, rekaman,dan penyimpanan kurva proses pengolahan panasTingkat bawah menggunakan pengontrol suhu industri PID Eurotherm 3504 dengan akurasi kontrol ± 1 °C dan keseragaman suhu tungku dalam ± 3 °C selama tahap penyimpanan. Zona pemanasan dikonfigurasi sebagai 2 zona yang terhubung dalam konfigurasi bintang.Alarm suhu tinggi suara dan visual, dan pemotongan arus otomatis. Pengatur suhu memiliki fungsi penyesuaian diri online yang menghitung parameter PID optimal berdasarkan karakteristik termal sebenarnya dari tungku,tingkat pemanasan penyeimbangan terhadap overshoot. III. Konfigurasi lapisan tungku dan elemen pemanas Lapisan tungku menggunakan kapas serat tahan api standar, dengan kedua dinding dan atap dibangun sebagai struktur serat sepenuhnya dengan ketebalan isolasi total tidak kurang dari 240 mm.Blok serat dilipat mengalami pra-kompresi sekunder sebelum pemasangan, mencapai kepadatan kompresi tidak kurang dari 230 kg/m3, dan diikat ke cangkang atap tungku dengan batang bulat baja tahan karat.,Stabilitas termal yang baik, dan ketahanan kelelahan termal. Elemen pemanas adalah strip tahan paduan 0Cr25Al5, ditekan dengan cetakan khusus untuk menghindari kerusakan pengolahan.memungkinkan perawatan dan penggantian yang nyaman dan cepat. Selama pemasangan, washer keramik ditempatkan di antara dinding serat dan strip resistensi untuk mencegah kontak langsung antara permukaan serat dan strip,dengan demikian meningkatkan disipasi panas dari stripKedua sekrup keramik dan washer terbuat dari bahan alumina tinggi dan sinter pada suhu tinggi untuk memastikan kekuatan yang cukup dan umur layanan.Strip resistensi digantung di sekitar ruang tungku, yang memfasilitasi disipasi panas dan sirkulasi aliran udara.6 W/cm2 ¢ nilai di bawah batas desain konvensional untuk pita resistensi, dimaksudkan untuk memperpanjang umur layanan elemen di bawah siklus pemanasan dan pendinginan yang sering. IV. Sirkulasi Udara Panas dan Sistem Panduan Udara Sebuah kipas sirkulasi tahan suhu tinggi dengan nominal 7,5 kW dipasang di atap tungku.dengan bantalan pendingin udara untuk mengakomodasi lingkungan atap suhu tinggi. Kap air panduan memaksimalkan komponen longitudinal dari gaya sentrifugal yang dihasilkan oleh kipas, menekan udara panas ke bawah.Udara kemudian melewati benda kerja dan ditarik kembali ke inlet kipas dari bawah, membentuk lingkaran sirkulasi tertutup.Jalur aliran udara ini memastikan keseragaman medan suhu dalam ruang tungku dan merupakan desain pendukung untuk metode pemuatan suspensi , memungkinkan aliran udara untuk melewati. V. Bahan Pengangkatan Keranjang dan Mekanisme Penguncian Pintu Tungku Mekanisme pengangkat keranjang bahan terdiri dari lilin listrik, rantai pengangkat cincin, dan blok katrol.Pencet adalah unit kontrol listrik dua kecepatan dengan kecepatan tali hingga 18 meter per menit, memenuhi persyaratan untuk cepat turun ke dalam air; fase naik menggunakan kecepatan lambat untuk mengurangi dampak inersia ketika benda kerja dan keranjang memasuki tungku.Winch memiliki kontrol inching dan perangkat self-locking, yang memungkinkan untuk berhenti di posisi apapun. Mengingat lingkungan tungku suhu tinggi, rantai cincin 16Mn digunakan. Sistem roda dipasang di bagian atas tubuh tungku,terdiri dari 4 katrol dan 4 set bantalan, memastikan pengangkatan dan pengurangan keranjang yang lancar. Pintu tungku terletak di bagian bawah badan tungku dan bergerak secara lateral, dengan rel panduan di sisi untuk menjaga gerakan horizontal.Saat menutup, silinder mendorong pintu ke posisi tertutup dan terus menerapkan tekanan, mengangkat pintu ke atas melalui mekanisme tuas di sisi untuk menekan erat terhadap tubuh tungku.Mekanisme angkat dan mekanisme pintu tungku saling terkunci: mekanisme pengangkat hanya dapat dihidupkan dan dioperasikan setelah pintu tungku terbuka sepenuhnya (di mana daya elemen pemanas telah dipotong).Logika interlock ini mencegah kerusakan peralatan dari kesalahan operasi ketika pintu tidak terbuka. VI. Waktu Transfer Pemadam dan Tangki Pemadam Waktu transfer pemadaman didefinisikan sebagai waktu dari pembukaan pintu tungku hingga pencelupan penuh benda kerja dalam air, dengan persyaratan desain tidak lebih dari 10 detik.Parameter ini sangat penting untuk proses pengolahan larutan paduan aluminium., semakin tinggi laju pendinginan melalui rentang sensitif kepanasan, dan semakin baik efek penguatan penuaan. Tangki pemadam adalah konstruksi yang bergerak, digerakkan oleh motor 2,2 kW. Dua pompa sirkulasi 3 kW dipasang di tangki untuk terus-menerus menggerakkan air selama pemadam,menjaga suhu air yang seragam dan mempercepat transfer panas dari permukaan benda kerja. Tangki dilas dari pelat baja tebal 5 mm dan diuji untuk kedap air. gerobak mobile dilas dari 12 # saluran baja,dengan bagian depan berfungsi sebagai area meja kerja rangka material dan bagian belakang sebagai tangki air, dengan tiga set roda (satu set adalah roda penggerak). VII. Urutan Tindakan Proses Urutan tindakan peralatan lengkap adalah sebagai berikut: 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.