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STEP 1: Procurement, Material Storage, Traceability

Procure Maruichi spec HRC, raw materials specially designed for Maruichi group, from Japanese steel manufacturers to ensure that final products will be top-notch.
Materials are then stored and managed in the system to maintain the traceability throughout the production process.

STEP 2: Production Preparation, Roll-Forming

After the HRC is slitted, the slit coils are accumulated inside the looper, which allows the material to be fed continuously into the roll-forming line. Roll-forming line changes the flat slit coils into round pipe shape.

STEP 3: High-Frequency Welding

Both edges of roll-formed slit coils are then pressed against each other, and high frequency electric current is applied to melt and joint them, making them into welded pipe.

STEP 4: Sizing

Welded pipe then goes thru sizing process, series of dies mechanically squeezing it to become the desired shapes with required dimension tolerance.

STEP 5: Automatic Cutting

Programmed automatic cutting machine chases the welded pipe while it runs thru the production line, and cut it to the length required by customers.

STEP 6: Tube end lathing

Both pipe ends are lathed to be suitable for handling.

STEP 7: Packing

Pipes are bundled to the order standard for shipping.

STEP 1: Procurement, Material Storage, Traceability

Procure Maruichi spec HRC, raw materials specially designed for Maruichi group, from Japanese steel manufacturers to ensure that final products will be top-notch. Materials are then stored and managed in the system to maintain the traceability throughout the production process.
(Raw material Thickness : 1.2~4.5mm)

STEP 2: Acid Cleaning

HRC goes thru 6 tanks for continuous cleaning by HCl acid solution to remove its surface scale and rust. Acid solution then circulates into acid regeneration treatment system.

STEP 3: Hot Water Rinsing

Acid cleaned coil then goes thru the hot water shower to rinse off the acid solution.

STEP 4: Edge Trimming

Both edges is trimmed to the desired width and smooth shape for the next processing. Coil is the re-coiled and weighed.

STEP 5: Cold Rolling

Coil is transferred and set onto the pay-off reel of 6 High Cold Rolling Mill, which rolls the coil while pressing it by 6 rolls(2 back-up, 2 intermediate, 2 work) . Coil’s dimensional accuracy is achieved to the order specification, (0.180-2.00mm), making it cold rolled coil.

STEP 1: Material Set-up

Cold-rolled coil sheet(or pickled hot rolled coil) is set onto the payoff reel. Sheet end is welded with another coil’s edge which allows continuous production.

STEP 2: Pre-treatment

Sheet is treated and cleaned with NaOH alkaline solution to remove surface impurity.

STEP 3: Heat Treatment

Sheet is exposed to direct and indirect heat to achieve ideal surface condition for the galvanizing process. In addition, mechanical property is carefully controlled to give the necessary strength for the end use.

STEP 4: Galvanizing, Zinc-Aluminum Coating (55% Al-Zn)

Sheet is dipped into molten Zinc or Zinc-Aluminum to coat it with corrosion resistant coating layer. Coating mass is controlled to meet the order specification.

STEP 5: Cooling

Coating layer is rapidly cooled to form the desired property.

STEP 6: Surface treatment

Surface quality and dimension is controlled thru skin-pass mill, tension leveler, then resin is applied to provide additional corrosion resistance.

STEP 7: Re-coiling and Packing

Sheet is recoiled and cut to the specified weight range of orders. Packing is applied to provide the adequate protection through the transportation.

STEP 1: Material Set-up

Galvaleum (Zinc-Aluminum coated steel) sheet in coil is set on is set onto the payoff reel. Sheet end is conjoined with another sheet’s end, which allows continuous production

STEP 2: Entry Looper

Enough amount of sheet is accumulated in the entry looper so that during the material Set-up process above, the production line is continuously fed with enough material.

STEP 3: Surface Cleaning

Sheet surface is cleaned with iron brush to improve adhesion then cleaned with hot water.

STEP 4: Chemical coating

Chemical is applied on the surface to protect the surface from oxidation and to increase the adhesion between the sheet surface and paint coating layer

STEP 5: Painting

Primer coating is applied on the sheet surface, then top coating is applied to provide the desired color both on the top side and back side.

STEP 6: Tension levelling

Sheet dimensional accuracy, which is affected at the different stages of production, is corrected to meet the order specification.

STEP 7: Exit Looper

Color Painted Sheet is accumulated in the exit looper to allow continuous production.

STEP 8: Re-coiling and Packing

Sheet is recoiled and cut to the specified weight range of orders. Packing is applied to provide the adequate protection through the transportation.