1. What is structural steel?
- Steel structure is a product line processed and manufactured from cast iron and steel by mechanical technologies to serve people, transportation, industry, military.
- Steel structure products: industrial factories, offices, fences, bridges, conveyors, ...
2. Input materials for the production of steel structures
For the production of steel structures, raw materials are carefully checked.
– Characteristics, dimensions and geometry of steel structures
+ In steel structure, the default unit is mm (millimeter).
. For example: TL 6000x1500x10 corrugated iron is 6m long, 1m wide, 5mm thick
+ Between H and I steel, H steel has the same belly height and wing length, different I
+ Round steel: D (200×10)
+ Roofing sheet is also calculated in mm, color is specified in English (Red = R). Roofing corrugated iron is produced in rolls, the processing unit uses a straightening machine, rolling it into the following roofing sheet
Chemical and mechanical properties:
+ Steel has 2 types according to the most common JIS standards, SS400 and Q345
. SS400: Low tensile strength (strength, yield strength, relative elongation) where:
Yield: hydraulic clamp pulls the ends of the steel, when the steel crystals start to move -> reach the yield point
Durability limit: when broken
Elongation: Subtract the original length from the length after stretching
. Q345: more advanced, higher stats than SS400
(*): There are 2 types of steel plate, shape steel only SS400
+ Galvanized products, usually electro-galvanized or hot-dip galvanized (SP dc plated when required by contract)
. Electroplating: thin coating, less durable but cheaper and more beautiful
. Hot-dip plating: much more durable (10 times thicker plating) but less aesthetically pleasing
. Colored corrugated iron: galvanized sheet is hot dipped compressed air blown, surface chemical treatment, then painted.
+ Panel: using fiberglass insulation to cover the corrugated iron.
- Sensory recognition features
+ Good materials must have the company's identification mark by paint or badge, etc., of origin, clear COCQ, must be packed methodically, surface not oxidized, not pitted, not damaged. has a different color than normal iron oxide
+ Colored sheet must not scratch paint, must have proof of plating thickness, paint thickness, must be verified by ruler, tested by tensile test method
+ All materials must be digitally checked, appraised and accepted, ensuring the prestige and quality of Hai L:ong products.
3. Processing and product quality control process of Hai Long steel structure
-Processing > Importing materials > Marking, keeping it separate > Cutting operations > Drilling to create holes > Rough jigs > Rough welding > Finished jigs > Welding > Cleaning, grinding > Primer > Inspection and acceptance > Packing
– The production process is only started after having the documents signed by the factory director (the dossier includes the list of components to be produced, along with the specification, thickness, etc.)
– The production order is only signed after it is approved, received advance from the investor, sufficient materials, approved by the Board of Directors and approved design drawings.
- Product quality control
– Check bolts, paint surface, …, based on JIS and design contract by measuring, based on sensory, COCQ, inspection -> materials are only used after KCS meets the requirements
– Manufacturing checks: (operations) are performed sporadically, but throughout the process.
Steel structure projects of Hai Long https://hailongjsc.vn/danh-muc-du-an/du-an-ket-cau-thep/