Roller zero mesh belt furnace heat treatment method for controlling the decarburization

The present invention discloses a mesh belt furnace roller control method of decarburizing zero thermal treatment including quenching, tempering and three detecting step, innovative in that: said quenching step is quenched in quench zone mesh belt furnace, using methanol, propane, nitrogen and carbon potential control three kinds of atmosphere, quenching process, the flow of controlled atmosphere divided into three areas, a first, a second region nitrogen gas and propane, a two-part control, a portion with a constant low flow 0.5 1L / min, another portion of the oxygen sensor using the automatic compensation control, which leads to insufficient carbon potential 2-3L / min, nitrogen and methanol third regions, respectively, the flow rate 6-6.4m3 / h and 4-4.5m3 / h . Roller heating time of 52-60 minutes, the quenching temperature of 850 ± 5 ℃, carbon potential controlled at 0.7-0.8% stabilizer; the tempering phase, the tempering temperature of 160-165 deg.] C, holding time of 180-210 minute. The method of the present invention is effective to solve the conventional control process, at a high carbon potential by real easy and low carbon potential problem easily depleted carbon.