CORPORATION Jonan Steel

manufacturing process

Aiming for low cost and high quality,we have established our own production line developed using advanced technical capabilities.
We provide products under a thorough management system, from order receipt, manufacturing, to shipping.


STEP-01

Detection of radioactivity of iron scrap
We check if there are radioactive substances in iron scrap by "Radioactive ray detection monitor" as a first step.
The inspection is done by trailer track basis. If it contains,the iron scrap will be returned to iron scrap wholesaler.
There are so many substances surround us, which radiant rays is used for, such as medical equipment, various analyzing equipment, etc. We strictly prevent radioactive substances to be in our plant.

STEP-01

Acceptance and mixing of iron scrap
The iron scrap collected is unloaded using a huge magnet, then the scrap is selected in order by each class and stored in the yard. Later, we mix the scrap iron in order to ensure that the chemical composition will be even when the scrap is melted, then feed the mixed scrap into the electric furnace.

STEP-01

Electric Furnace
We melt the iron scrap in an electric furnace using arc discharge. In addition, we adjust chemical compositions by removing impurities from the melted steel and adding auxiliary materials.
Chemical compositions have great influence on the mechanical property of products. We use an analyzing system to inspect the product, and after we have refined the products to meet to our company standards, we top liquid steel in to a ladle.

STEP-01

Tapping liquid steel
One charge is about 70 tons, and we can produce about 25 charges per day.

STEP-01

Continuous Casing
Next, the liquid steel from the electric furnace is carried to the continuous casting process, and we produce the billets which are the basis for deformed steel bars are produced here.

STEP-01

Billet
A billet is a block of steel in a square bar shape. Our company produces billet in size 125mm×125mm. Length 3〜4m.

STEP-01

Rolling Mill
Billets are passed through 18 rolling machines in order, to gradually extend (roll) to make bar steel. In the final rolling machine, knots and marks are stamped into the bar steel, and the bar steel is transformed into the deformed steel bar shape.

STEP-01

Reforming & Cooling
Hot deformed steel bars are cooled down to normal temperature.

STEP-01

Bundling
The deformed steel bars are cut to specified lengths, and bundled in to specified numbers.

STEP-01

Inspection
Various inspections are carried out to check whether or not each deformed steel bar product meets the standards. Qualified products are shipped out.

STEP-01

Shipping
The products are loaded on trailer trucks according to the details of each order, and delivered to customers according to the specified delivery dates.