Steel Plate Induction Hardening and Tempering Line | Working Flow

Overview of Plate Induction Heat Treatment Line

Steel plate induction hardening and tempering line is a dedicated continuous heat treatment unit for medium and thick steel plates. It is widely used in engineering machinery, container manufacturing, shipbuilding and heavy equipment industries. Many manufacturers face unstable hardness, uneven metallographic structure and low production efficiency with traditional furnace heating. Forever Electromechanical has optimized the whole workflow of this induction line, realizing automatic, controllable and repeatable plate quenching and tempering for global heavy industry clients.

Step 1: Automatic Feeding and Positioning

The first link is automatic feeding and precise positioning. Raw steel plates are sent to the roller conveyor by loading mechanism. The photoelectric sensor detects plate length, width and thickness, and transmits data to the PLC control system. The system automatically adjusts conveying speed, induction coil gap and power parameters according to plate specifications. This step avoids manual positioning deviation and ensures every plate enters the heating section with consistent posture. It is suitable for alloy steel, carbon steel and wear-resistant steel plates of different sizes.

Step 2: Induction Preheating and Quenching Heating

After positioning, the plate moves into the induction heating zone. The IGBT induction heating power supply generates alternating electromagnetic field, heating the steel plate from inside to outside rapidly. The line adopts segmented heating design: preheating section reduces temperature gradient to prevent plate deformation; the quenching heating section raises the plate to the target austenitizing temperature. Infrared temperature sensors conduct real-time closed-loop monitoring, keeping temperature fluctuation within a narrow range. Uniform heating effectively reduces oxidation and surface decarburization compared with gas furnaces.

Step 3: Synchronized Quenching Cooling

When the plate reaches the preset quenching temperature, it enters the spray cooling chamber immediately. High-pressure cooling nozzles are arranged on upper and lower sides, spraying cooling medium evenly on the plate surface. The cooling flow rate and pressure are adjustable. Controlled rapid cooling forms uniform martensite structure, which greatly improves surface hardness and wear resistance. The linkage design of heating and cooling prevents over-cooling or insufficient cooling, effectively reducing plate warpage and scrap rate.

Step 4: Tempering Heating and Heat Preservation

Quenched plates are then transported to the tempering section. Low-medium frequency induction heating raises the plate to tempering temperature for holding. This process releases huge internal stress generated during quenching, adjusts metallographic structure, balances hardness and toughness. After tempering, the steel plate will not crack easily under impact load. The continuous mode avoids the batch limitation of box furnaces, supporting uninterrupted production.

Step 5: Post Cooling, Inspection and Discharging

The final stage includes slow cooling, automatic detection and discharging. After tempering, plates go through the air cooling section to lower temperature gradually. The online detection module records hardness and flatness data. Qualified products flow to the unloading platform; unqualified ones will be screened out. All production data can be stored for traceability. Forever Electromechanical provides customized layout and parameter tuning services. The complete workflow helps plate manufacturers get stable heat treatment quality and cut comprehensive production costs. 

Overseas manager:Mr. Wang

Email:tom@foreverfurnace.com

Phone/Wechat/Whatsapp:+8613303078975