Pre-engineered Structural Steel Industrial Real Estate Building Construction
What is Pre-engineered Steel Building?
Pre-engineered steel buildings are steel structures built over a structural concept of primary members, secondary members, roof and wall sheeting connected to each other and various other building components.
These buildings can be provided with different structural and non-structural additions such as skylights, wall lights, turbo vents, ridge ventilators, louvers, roof monitors, doors & windows, trusses, mezzanine floors, fascias, canopies, crane systems, insulation etc., based on the customer's requirements. All the steel buildings are custom designed to be lighter in weight and high in strength.
Model of Pre-engineered Steel Buildings
Applications of Pre-engineered Steel Buildings
Pre-Engineered Buildings are the most flexible solutions for contractors and owners. With the advantages of low cost, high durability, perfect quality control and fast erection; PEBs are used for various applications such as factories, warehouses, logistics center, showrooms, shopping malls, schools, hospitals, community buildings, etc.
Industrial Applications:
- Factories
- Workshop
- Warehouses
- Cold Storages
- Steel Mills
- Assembly Plant
Commercial Applications:
- Showrooms
- Supermarkets
- Offices
- Shopping Centers
- Exhibition Halls
- Restaurants
- Logistic Centers
- Multi-pupose Buildings
Public & Other Applications:
- Schools
- Hospitals
- Conference Halls
- Laboratories
- Museums
- Stadiums
- Farms
- Utility Shelters
- Pump Stations
- Aircraft Hangars
- Airport Terminals
Why Choose Pre-engineered Steel Buildings?
1. Cost Savings
Price per square meter can be 25%-30% lower than conventional steel buildings. Site erection cost is low because of faster erection times and easier erection process.
2. Quick Erection
All steel components are fabricated at the factory and linked by bolts at the site. So the erection process is fast, step by step, easy to install and requires simple equipment. 60% less construction time required compared with the tradtional R.C.C (reinforced concrete) building.
3. Flexibility
Pre-engineered steel buildings are flexible in any requirement of design, easy to expand in the future and also economically with low transportation costs.
4. Energy Efficiency
Nowadays, pre-engineered buildings are the green solution for the environment with CO2 reduction, energy efficiency, and recyclability.
Components of Pre-engineered Steel Building
Pre-engineered metal buildings consists of following components:
- Primary Members / Main Frames
- Secondary Members / Cold Formed Members
- Roof & Wall Panels
- Accessories, Buyouts, Crane System, Mezzanine System, Insulation, etc.
- Sandwich Panels
Primary Members / Main Frames
Primary members are the main load carrying and support members of a pre-engineered building. The main frame members include columns, rafters and other supporting members. The shape and size of these members vary based on the application and requirements.
Secondary Members / Cold Formed Members
Secondary structural framing refers to purlins, girts, eave struts, wind bracing, flange bracing, base angles, clips and other miscellaneous structural parts.
Purlins, girts and eave struts are cold formed steel members which have a minimum yield strength of 345 MPa (50,000 psi) and will conform to the physical specifications of GB/ISO/CE or equivalent.
Roof & Wall Sheets/Panels
Standard steel panels are 0.3, 0.4, 0.5 mm or 0.6 mm thick and have a minimum yield strength of 345 MPa. Steel panels are hot dipped and galvanized with zinc or zinc-aluminium coating. The base material is pretreated, before applying a corrosion resistant primer and top coat. The combined thickness of the painted film is 25 microns on the front side and 12 microns on the reverse side.
Other Building Accessories
Other building accessories include anchor bolts, fasteners (bolts, nuts, turnbuckle, expansion bolts), gutters, downspouts, doors, windows, ventilators, skylight panels, louvers and all other building-related materials.
Manufacturing Process and Quality Control
A: Material Receiving Procedure
- Verify the receiving documents and quantity of the received material by stores
- Submit the load for QC inspection by stores
- Visual inspection to confirm surface condition and for any damages
- Dimensional inspection checking length, width, depth, thickness etc.
- Verification of supporting documents like MTC
- Preparation of Incoming Material Inspection Report
B: Preparation of Material
Preparation of Plates:
- Drawings transferred to storage device using expert software
- Drawings copied into plate processing machine
- Automated machine senses plate length and carries out processing
- Punching of part mark on the plate
- Drilling of plates as per NC files
- Plasma cutting of plates
Preparation of Beams/Tubes etc.:
- Fabrication drawings prepared by design department
- Automated cutting and drilling machine processing
- Transfer to fit-up section after completion
C: Fit-up
- Fabrication drawings issued by production engineer
- Prepared beams and connection detail items collected for fit-up
- End plates, gusset plates, stiffeners, purlin cleats fixed by tack welding
- QC inspection after fit-up completion
D: Welding & Grinding
Submerged Arc Welding Procedure:
- Plan jobs to be welded
- Clean welding location free of dust, oil, grease
- Set wire feed and voltage for welding
- Maintain fillet size parameters per GB50661-2011 standard
- Remove spatters and slag completely after welding
- Grind off burrs, sharp edges and excessive reinforcements
- QC inspection after completion
MIG Welding Procedure:
- Plan jobs to be welded
- Clean welding location free of dust, oil, grease
- Set wire feed and voltage for welding
- Maintain fillet size parameters per GB50661-2011 standard
- Remove spatters and slag completely after welding
- Grind off burrs, sharp edges and excessive reinforcements
- QC inspection after completion
E: Blasting
- Tool Box Talk performed by Foreman for every task
- Working area barricaded with information notices
- ID of fabricated steel recorded for traceability
- Raw material steel sections craned onto "in-feed" rack
- Material cleaned with high pressure air to remove dust
- Automated blasting process using six internally mounted wheels
- Steel emerges fully cleaned (Grade - SA 2/2.5)
- Full PPE required for personnel
F: Painting of Fabricated Material
- QC inspection of blasted surfaces before priming
- Ambient conditions checked and recorded before application
- Surface must be at least 3˚C above dew point temperature
- Relative humidity must be 85% or below
- Paint applied by Airless spray method
- WFT (Wet Film Thickness) readings taken during application
- Only experienced spray applicators used with appropriate PPE
Specification of Painting System:
- Primer coat: Per the project requirement
- Second coat: Per the project requirement
- Third coat: Per the project requirement
- Touchup at site - after erection
G: Loading and Shipping
- Receives finished components from production department
- Store components properly job wise in the yard
- Arrange trucks from contract signed truck companies
- Loading starts after getting clearance
- Copies of all documents kept in Job file
Quality Standards & Control
With 20 year warranty in the steel building industry, our company has standard on the quality of steel building. We have acquired the ISO9001 and CE certificate. The followings are the related standard that we strictly follow whether for the design and fabrication of steel buildings:
- GB/T1591-2008/2018
- GB/T11263-2010
- GB/T 2518-2008
- GB/T12754-2006
- GB/T 1228-2006
Fillet Weld Size Quality Control
1. Purpose
To ensure the quality of fillet weld, meeting up the technical requirements of welded members and improve the standardization of our fabrication.
2. Application Scope
This manual is applying for the design, fabricate and inspection for the fillet weld size.
3. Fillet Weld Leg Size Requirements
Definition: Length of catheti from maximum isosceles triangle that drawn from the section of fillet welding seam.
Minimum fillet weld size: K≥1.5×t (t--thickness of thicker welding member)
Maximum fillet weld size: K≤1.2t (t--thickness of thinner welding members)
Edge welding: When t≤6mm, K≤t; when t>6mm, K≤t-(1~2)mm
Circular holes: K≤(1/3)d (d--diameter of circular hole)
Maximum without groove: Should not be more than 17mm
Selection of Fillet Weld Size
| Form of fillet weld leg |
K(fillet weld size) value |
Note |
| Fillet weld without groove |
K=(0.7~1)t and≤15mm |
for most of the steel structure buildings |
| Fillet weld without groove |
K=(0.5~0.6)t |
for the strengthening ribs and other secondary members |
| Fillet weld with groove (CJP and PJP) |
K=t/4 and K≤10mm |
for most of the steel structure buildings |
| Fillet weld with groove (CJP and PJP) |
K=t/2 and K≤10mm |
important members (crane beams or connection between web plates and flange plates) |
Minimum Fillet Weld Size Chart
| Parent metal thickness(t)(mm) |
Minimum fillet weld size |
| t≤6 |
3 (minimum value being 5 for crane beam) |
| 6 |
5 |
| 12 |
6 |
| t>20 |
8 |
KXD's H Section Manufacturing Equipment and Process
Steel plate cutting → H section assembly → Automatic welding → H section strengthening → Assembly → Manual welding → Shot blasting → Painting → Storage
I. Steel Plate Cutting
Equipment: Portable CNC Fire-cutting machine (Model: CNCDG-1530)
Application: Steel plate cutting (5-100mm thickness), beveling of the edge
II. H Section Steel Assembly
Equipment: H section steel assembly machine (Model: Z20B)
Application: H type assembly, flange width 150-800mm, web height 160-2000 mm
III. Automatic Welding
Equipment: Gantry-type submerged arc automatic welding machine (Model: LHA5ZB)
Application: Assembly welding of H section steel up to 800mm×2000mm cross section
IV. H Section Steel Strengthening
Equipment: H section steel strengthening machine (Model: YTJ60B)
Application: Correcting deformation of I beam or H section steel flange plate
VII. Shot Blasting
Equipment: 10-ramming heads shot blasting machine (Model: QH1525)
Application: Shot blasting of section steels, up to Sa2.5 Grade
VIII. Painting
Equipment: Airless sprayer (Model: CPQ9CA)
Application: Surface paint of structural members, Pressure ration: 32:1
