57results about How to "The production process is compact" patented technology

The invention relates to a production method of austenitic stainless steel, which comprises the following steps of: a, mixing different low-grade nickel-chromium pig iron in an electric furnace, blowing, desiliconizing and decarbonizing to obtain a stainless steel mother liquor; preparing Cr to be about half of a finished product according to the content requirement of a stainless steel finished product, and properly preparing Ni in the stainless steel mother liquor in the electric furnace by using a grade high-carbon ferrochrome; b, adding the stainless steel mother liquor obtained in the step a to an AOD furnace, adding the high-carbon ferrochrome, laterally blasting air, oxidizing by using a gun and flowing out slag; c, adding metallurgical lime, high-carbon ferrochrome, ferronickel and waste steel to carry out primary decarbonization and secondary decarbonization, adjusting carbon content to the level required by the finished product; and e, finely adjusting components and adjusting temperature in an LF furnace to obtain the austenitic stainless steel. The invention has the advantages of low energy consumption, low cost and stable product quality.

The invention relates to a rare-earth ore crushing and sieving device which comprises a crushing transport chamber, a solid-liquid separation chamber, a drying preheating chamber, an ore powder temporary storage box, a sewage filtering chamber and a water circulation system. Through special arrangement for all the parts, especially arrangement of the sewage filtering chamber, the water circulatingsystem and the drying preheating chamber, in the rare-earth ore crushing process, water resources can be recycled, heat quantity can achieve maximized comprehensive utilization, and the environmentalfriendliness of the crushing process is strengthened.

The invention discloses a method for preparing a high-strength polyacrylonitrile-based carbon fiber precursor. The method comprises the steps of: using azodiisobutyronitrile to trigger acrylonitrile and a comonomer to perform homogeneous solution polymerization in dimethyl sulfoxide to obtain spinning solution, and controlling the temperature of the spinning solution to be between 40 and 70 DEG C and the solid content to be between 18 and 24 percent; performing monomer removal on the spinning solution under the pressure of between -60 and -78KPa, and performing deaeration treatment under the pressure of between -78 and -97KPa; then extruding the spinning solution into a spin duct in a coagulation bath with a temperature of between 35 and 65 DEG C and a dimethyl sulfoxide concentration of between 50 and 70 percent for molding through a spinneret, and obtaining PAN-based as-spun fiber through 45 to 75 percent of minus stretch in the coagulation bath; then molding and stretching through a secondary coagulation bath, a third coagulation bath, a fourth coagulation bath and a fifth coagulation bath; and obtaining the high-strength polyacrylonitrile-based carbon fiber precursor through solvent removal by water scrubbing, hot water stretch, oiling, drying and densification, steam stretch, and hot air setting. The tensile strength of the high-strength polyacrylonitrile-based carbon fiber precursor reaches 10.2cN / dtex.

The invention relates to a nitriding furnace system, which comprises a first nitriding furnace and a second nitriding furnace, and a gas control station is connected between the first nitriding furnace and the second nitriding furnace. The first nitriding furnace includes a base, a material basket, an inner tank, a central air duct, and a thermal insulation shell, the material basket is hoisted on the base, and the inner tank and the thermal insulation shell are fixedly connected to the base through a locking device Above, the central air duct is arranged in the middle of the first nitriding furnace. The beneficial effects of the present invention are as follows: 1) The continuous production of iron nitride alloys is realized by switching between two nitriding furnaces, and the efficiency is greatly improved; 2) The heat exchange system is adopted to make full use of the waste heat of materials, and to speed up the cooling speed, which is both environmentally friendly and Economical; 3) The method of heating the material on both sides increases the amount of material added in a single batch, improving the efficiency and the stability of the nitrogen content of the product; 4) The overall structure design is ingenious, and the entire technical solution occupies a small area and is low in cost , which is convenient for large-scale promotion and use.