For steel bar heat treatment, achieving uniform hardness along the entire length is a common challenge. Many manufacturers face head-to-tail temperature differences that lead to rejected batches and high energy consumption.

Hebei Yuanto Electromechanical Equipment Manufacturing Co., Ltd. recently delivered a complete steel bar quenching and tempering line to a wind power fastener producer in Hunan Province, China. The customer processes Φ65-75 mm alloy steel bars (length ≤6.5 m) for high-strength anchor bolts and wind power fasteners.

Customer’s original pain points:

Obvious hardness difference between head and tail (±5 HRC)

Bending deformation after quenching

Energy consumption above 450 kWh/ton

Our solution:

Quenching power: IGBT 760 kW / 2.5 kHz

Tempering power: IGBT 420 kW / 1.5 kHz

Tilted roller conveyor (18-21°) with 304 non-magnetic water-cooled rollers between heating sections

Closed-loop temperature control using Raytek infrared pyrometers + Siemens S7 PLC

Automatic power regulation based on real-time bar temperature and feed speed

Actual results after commissioning:

Hardness uniformity improved to ±1.5 HRC along the full length

Bending amount reduced to ≤0.5 mm/m

Energy consumption dropped to 380 kWh/ton (saving over 15%)

Production capacity: 2 tons/hour

Complete system supplied by Hebei Yuanto:

IGBT intelligent induction heating power supply (DSP+FPGA+ARM control)

Quenching heating coil and tempering heating coil (customized geometry)

High-efficiency closed cooling tower + plate heat exchanger

Water spray quenching system with adjustable flow

PLC/HMI automation with recipe management for different steel grades

Online infrared temperature monitoring and historical data traceability

If you are struggling with hardness inconsistency or high energy costs on your steel bar heat treatment line, contact Hebei Yuanto. Provide your bar diameter, length, material grade, and target hardness – we will send you a customized induction heating solution within 48 hours.