Induction heat treatment of spring steel wire for vehicle suspension

The vehicle suspension spring wire diameter mostly [Phi] . 5 - [Phi] 12mm, material is 65Mn, 60Si2Mn, 55SiCrA , A Class tensile strength requirements 1500~ 1650 MPa, B class requirements for the tensile strength of 1750 ~ 1600 MPa, the rear stretch length ratio 〉30% o

The induction heat treatment of the spring steel wire of the vehicle suspension is shown in the figure. The production and operation process is as follows: the steel wire is discharged by a double-wheel pay-off machine, passes through the pinch rod, straightens the spoke, and enters the first induction heating furnace for preheating, then austenite allelopathic heating, and after cooling to martensite Into the second induction heating furnace, the inductor is tempered, and then sent to the holding room by the pinch phase, and the air-cooled (or water-cooled) air-cooled (or water-cooled) wire is taken up by a double-wheel take-up machine from the holding room. After coiling, the steel wire is cut at the same time and taken up by the other round of the double-wheel take-up machine. During normal production, a shift can be continuous and uninterrupted for 8 hours . The preheating temperature is about 700 °C, the frequency is 8kHz; the austenitizing temperature is about 900 °C, the frequency is 50kHz, and the synthetic quenching cooling medium is used for cooling; the tempering temperature is 400~ 450 °C, and the frequency is 8kHz. The austenitizing temperature and tempering temperature are measured by an infrared thermometer, and the output voltage of the variable frequency power supply is automatically adjusted through PID to adjust the temperature. The heating time (20~900 ℃) is 5 ~ 10s.

Induction heat treatment of spring steel wire for vehicle suspension

1 a steel wire 2-pinch spread 3-straightening of the spoke 4-induction heating preheating (8kHz) 5-induction heating austenitizing ( 50kHz) 6-quenching cooling 7-induction heating tempering (8kHz) 8-tempering Insulation room 9 a cooling room 10- pinch the spoke

11— Cutter 12—Steering wheel 13—Double-wheel pay-off machine 14, 15—Infrared measuring and control instrument 16—Take-up machine