Learn how overpass and bridge guardrails are fabricated for vehicle and pedestrian safety. Discover material selection, crash engineering, and real-world installations.
Reading an Overpass Guardrail Fabrication Drawing Package
Overpass and bridge guardrails prevent vehicles and pedestrians from falling from elevated roadways and walkways. These barriers must withstand vehicle impact forces, resist weather exposure, and meet stringent crash safety standards. At Fulei Metal, we fabricate overpass guardrail components for infrastructure contractors across Europe and Southeast Asia.
Overpass Guardrail Types
Bridge traffic barriers prevent vehicles from leaving the roadway on bridges and overpasses. Pedestrian guardrails protect pedestrians on elevated walkways and bridge sidewalks. Combination barriers provide both vehicle and pedestrian protection. Median barriers separate opposing traffic directions on bridges. Transition barriers connect bridge barriers to approach guardrails.
Material Options for Overpass Guardrail Fabrication
Hot-dip galvanized steel is the standard material for overpass guardrails, providing decades of corrosion resistance in exposed elevated environments. We use 3.0 to 6.0 mm steel sheet and tube depending on crash test requirements. For coastal environments, stainless steel (grade 316L) provides superior corrosion resistance. Powder coating over galvanizing provides color options and additional protection. Concrete barriers may incorporate steel cladding for aesthetic purposes.
Decisions to Make Before Cutting Overpass Guardrail Fabrication
Bridge traffic barriers must meet crash test standards appropriate to the roadway type and speed limit. Barriers must contain and redirect vehicles of specified size and speed without breach. Pedestrian barriers must resist horizontal loads of 1.5 to 3.0 kN per meter. Barrier height must meet standards: typically 800 to 1,370 mm for traffic barriers and 1,000 to 1,100 mm for pedestrian barriers. All components must resist wind loads at elevated positions. Drainage must prevent water accumulation on bridge decks. Aesthetic design should complement bridge architecture. Barriers must accommodate bridge thermal expansion and contraction.
Process Steps for Overpass Guardrail Fabrication
Our TRUMPF fiber laser cuts barrier post components, mounting plates, and connection hardware from flat sheet stock. Tube processing equipment cuts barrier posts and rails. CNC press brake machines form barrier profiles, mounting brackets, and transition components. Component assembly uses MIG welding for galvanized steel and TIG welding for stainless steel, with full-penetration welds at structural connections. Surface treatments include hot-dip galvanizing and powder coating.
Overpass Guardrail: The Attachment Carries the Load
On an elevated structure the fabrication questions change, because the steel is not standing on the ground – it is attached to something that moves, and the attachment is where the load goes. Post fixings are dimensioned for the substrate they land on rather than for the rail they carry, and where the substructure is concrete the fixing pattern is checked against the casting tolerances that the concrete actually achieves. Coating thickness is measured after galvanizing on a sample basis, on the flats and inside the profile, because the inside of a rolled section is consistently the thinnest part of the coating and the first place corrosion starts.
What to Send for Overpass Guardrail Fabrication Pricing
Overpass guardrail fabrication requires crash engineering, structural welding, and corrosion protection. Fulei Metal’s capabilities make us a trusted partner for elevated infrastructure safety projects.
Send drawings and we will check them against our DFM engineering review capability before quoting. You can also see how this fits into our custom sheet metal fabrication work, or read Public Guardrail Fabrication first if you are still comparing options.
Guardrail on a Footbridge: Height, Gap and Continuity
Guardrail for an overpass or a footbridge is governed by dimensions set externally — height above the walking surface, the maximum gap a component may leave, and the load the rail has to resist — and those have to appear on the drawing as stated numbers. They are not proportions that can be taken from an existing installation, because a rail that was compliant under one requirement may not be under another, and a rail that looks continuous may still leave a gap at a post that exceeds the permitted opening.
Continuity is the part that gets missed. The infill — bars, mesh or a panel — has to be continuous past the posts, and where a rail changes direction or steps at a ramp, the transition is where an opening appears. Those transitions are fabricated parts, and they need to be drawn rather than left to the installer to resolve on site.
Can you build to our guardrail schedule?
Yes. Send the schedule with the stated heights, gaps, load requirement and post spacing, and we will build to them and flag any transition or termination the schedule does not cover.
Who confirms the compliance?
Height, gap and load requirements, and the assessment of the complete installation, belong to the specifier, the engineer or the authority having jurisdiction. We fabricate to the dimensions and sections you state and tell you what we need in order to hold them.
Galvanizing Sequence and the Fixing Detail
Bridge and overpass hardware is hot-dip galvanized in nearly every case, and the sequence decides the service life: all cutting, welding and drilling done first, galvanizing after, so that every opening and every weld is coated. Anything drilled on site — for a fixing, for a cable, for a sign — breaks that coating and becomes the first rust point, and on a structure that is visible from the road below it shows quickly.
The base detail is the second issue. Water sits where a post meets a deck, and a base plate sealed against the deck without a drain path will hold it. A base plate with a drainage gap, or a spigot that lets water out, removes the problem; so does specifying the fixing as stainless where the post is galvanized, because dissimilar metal contact at a wet base is a corrosion cell waiting to happen.
Inspection follows the buyer drawing and the approved sample, with general tolerances to ISO 2768 unless stated. Stated heights and gaps are checked on a sample from each batch, and coating thickness is recorded. Material and coating documentation is issued per order — see material certification and traceability. Long runs are bundled and packed with separation; for export consignments see export packaging standards.
Need a Similar Part?
Most enquiries that start on a page like this are not an order for Overpass Guardrail Fabrication — they are a search for a factory that can make something like it. Send us your drawing, 3D model or sample and we will review the manufacturing process and the quotation requirements, then come back with a process plan, a price and a lead time.
We work from 2D drawings, STEP / DWG / DXF / PDF files, or a physical sample if that is all you have.
No complete drawings yet? Describe the part, send photos or a sketch, or send a sample — we can start from there. Discuss your project.
Trade Terms and Delivery
We quote under the standard Incoterms your logistics team already works with, and build the packing and documentation around the one you choose.
- EXW — you collect from our Ningbo facility and run export clearance through your own forwarder.
- FOB Ningbo — we deliver to the vessel at Ningbo port and handle export clearance.
- CIF — we cover carriage and insurance to your named destination port.
- DDP — we handle carriage, insurance, import clearance and duties through to your door.
Send your destination country, target delivery date and preferred trade term together with the drawing. Request a quotation.
Payment Terms
How a project is paid for is agreed before production starts, and the structure that applies to your order is stated on the quotation and on the order confirmation, so there is no ambiguity later.
- 30% advance payment with the order and the 70% balance before shipment — our standard structure.
- 70% advance payment with the order and the 30% balance before shipment — used for some projects.
- 100% payment in advance before production starts — used for some projects.
If your finance team works to a fixed structure, say so in the first enquiry and we will confirm what applies to your order before you commit. Request a quotation.
Quotation Time
We quote from your drawings. How long that takes depends on what the part asks for:
- Simple parts — quoted within 24 hours. Laser-cut blanks and bent components, supplied with complete 2D or 3D drawings. Mon–Fri, GMT+8.
- Complex assemblies — quoted after the drawing review. Payment kiosks, multi-part welded frames, enclosures with purchased hardware, or anything needing a coating or assembly trial. We confirm a quotation date once the scope is clear.
Production lead time is quoted separately, after drawing review and process confirmation. Send your drawings.
What stands behind this quotation
- Manufacturing since 20162,500 m² Ningbo plant — 3 laser cutting machines (including newer TRUMPF), 4 CNC press brakes and 10 welding stations.
- Shipped to more than 30 export marketsEnclosures, cabinets and formed parts supplied to OEM buyers across Europe, North America and Asia.
- 123 documented product casesMedical device housings, HVAC and heat pump enclosures, agricultural and livestock equipment, industrial hydraulics, material handling trolleys and EV charging cabinets.
- Factory evidence you can checkTUV Rheinland audit reference MIC-ASI243729 and Bureau Veritas reference MIC-ASR263630 available for buyer review on request.
Before you send drawings: project confidentiality is default · first-article inspection is carried out before a batch continues · pricing is staged from prototype quantity to repeat volume · pre-shipment photos and packing records are prepared when the project needs them.