2results about How to "Refined grain size" patented technology

The present application relates to the technical field of highway-railway dual-purpose transport equipment, in particular to a highway-railway dual-purpose steel rail double-frequency electric normalizing train, which comprises a vehicle body, a tool container and a mobile steel rail pressure-keeping double-frequency electric normalizing device are carried on the vehicle body; the vehicle body comprises a truck chassis assembly, a load-bearing frame and a hydraulic pump station are connected to the truck chassis assembly, and a set of telescopic hydraulic leg mechanisms are arranged at the front and rear ends of the truck chassis assembly respectively, and a wheel-rail running lifting mechanism is connected to the load-bearing frame; the present device is suitable for post-welding pressure-keeping double-frequency electric normalizing heat treatment operation of steel rail joints in seamless lines and urban rail transit. Furthermore, the device and the tool box are integrated and installed on a highway-railway dual-purpose vehicle, so that the working efficiency is improved, the on-and-off track operation and construction requirements of the device are facilitated, and the hoisting and carrying cost of the device can be greatly saved.

This invention relates to a forging method for stepped gear shafts from continuously cast billets with diameters of φ600~φ785mm. The method involves loading the continuously cast billet into a heating furnace, holding it at 700~800℃, and then raising it to 1230℃±10℃. The billet is then upset with the tail end facing upwards using a concave upsetting plate, with an upsetting height-to-diameter ratio of 0.6~0.7. The billet is then drawn on an upper and lower flat plate, with a reduction of 13~18% per pass, and rotated 90° per pass. Finally, the billet is drawn on upper and lower flat anvils, with a reduction of 18~22%, and fed into the anvils at full capacity, ensuring at least one [unclear unit] per two anvils. With a 5% anvil loading, the anvil is rotated 90° per pass. A 3150-ton hydraulic press is used to upset the riser end with a concave upsetting plate, resulting in a height-to-diameter ratio of 0.6 to 0.8. The billet is drawn to be 20 to 30 mm larger than the maximum step diameter of the stepped gear shaft. After scoring, the billet is kept at a furnace temperature of 1030±10℃. The small steps at both ends are forged into finished products, and the large steps are forged into finished products within the range of 760℃ to 790℃. This improves the actual grain size and banded structure qualification rate of the stepped gear shaft, reduces the need for one normalizing step, and improves the low-magnification structure.