The cold rolling of smls
is to change the martensite to the seamless steel pipe before the rolled piece enters the finishing extruder. Rough rolling is still carried out in a fully martensitic condition, and then the hot strip temperature is reduced to a change of Click below.
The nitriding treatment method of seamless steel pipe is mainly to use a nitriding furnace, put the seamless steel pipe into the material frame, and then use the driver to lift the product workpiece and place it on the bottom of the furnace for heating. In addition, it can make a nitriding furnace with a design scheme for lifting the load of the furnace door, and heat the workpiece vertically on the wall according to the special tools for lifting and hanging on the wall. The furnace shell of the nitriding furnace is generally driven by a reducer motor and an electric automatic lift. After the furnace cover is closed, the anchor bolts are also clamped to ensure the airtightness of the vacuum pump of the nitriding furnace. First vacuum packaging, and then enter N2 to carry out nitriding heat treatment process.
Nitriding treatment of seamless steel pipe refers to an organic chemical heat treatment method in which a certain substance at a certain temperature makes the surface of the workpiece of the organic chemical heat treatment process product. Nitriding furnace is used to carry out vapor nitriding heat treatment process in various steel mechanical parts, car curved glaze, transmission gear, motorcycle brake pads, mold shells, etc. In the field of non-ferrous plates, it can be used for bright and air-free oxidation quenching of copper materials such as air-conditioning copper pipes, copper coins, copper core wires, and copper rods in a protective atmosphere. Or use the air-free oxidation quenching heat treatment method for the vacuum pump N2 maintenance of thick-walled seamless steel pipes, short shafts, and various metal parts.
Obviously, because the heating temperature of the cold rolled slab in the seamless steel pipe area is lower than that of the basic cold rolling, the heating energy consumption can be greatly reduced, and the production capacity of the heat treatment furnace is also improved. The low heating temperature can also reduce the heating of the hot-rolled strip, thereby reducing the fatigue cracking and cracking of the hot-rolled strip caused by internal stress, and reducing the wear of the hot-rolled strip; ultra-low temperature cold rolling can also reduce the secondary zinc ash. , to improve the process performance of hot rolled products, and also to improve the operating speed of the pickling passivation line
. Life practice has proved that replacing the traditional cold-rolled quenched hot-rolled strip with the thin hot-rolled strip produced by hot rolling in the seamless steel pipe area can greatly reduce the product cost.