Description

80mm x 40mm x 5mm Galvanised Rectangular Box Section

Our Galvanised Rectangular Box Section is a strong and versatile steel hollow section protected by a hot-dip galvanised zinc coating. It combines the practical strength of steel box section with improved resistance to rust and atmospheric corrosion, making it particularly suitable for outdoor, agricultural, construction and general fabrication projects.

The hollow profile provides reliable structural performance while remaining practical to handle and fabricate. Products can be ordered cut to your required length, helping reduce waste and preparation time.

Technical Specifications

Key Features

• Hot-dip galvanised zinc coating for improved corrosion resistance
• Rectangular Hollow Section (RHS) profile with consistent external dimensions
• Strong and durable steel construction
• Good strength-to-weight ratio
• Suitable for cutting, drilling and fabrication
• Suitable for indoor and outdoor applications
• Available cut to your required length

Benefits

• Improved protection against rust compared with untreated mild steel
• Reduced maintenance in exposed environments
• Suitable for structural and general fabrication projects, subject to the required design specification
• Clean and practical finish for visible applications
• Cut-to-length ordering helps reduce material waste
• Available in a broad selection of sizes and wall thicknesses

Grade Information

Galvanised Steel Box Section is commonly supplied in S235JRH structural hollow section grade to BS EN 10219.

Selected sections may be supplied in S355J2H structural hollow section grade to BS EN 10219, where applicable depending on the section size, supplier and current stock availability. This does not mean that every section is available in both grades.

The galvanised coating is separate from the underlying steel grade. Where applicable to the supplied product, hot-dip galvanising is carried out in accordance with BS EN ISO 1461:2022.

If your project requires a specific material grade, including S235JRH or S355J2H, certification, coating specification or material traceability, please contact KI Metals before placing your order and obtain written confirmation from KI Metals.

Telephone or verbal discussions, customer order notes, notes included with drawings, and other instructions submitted with an order do not constitute confirmation of the material grade or supply requirements. A specific grade, certification, coating specification or traceability is only confirmed where KI Metals has provided written confirmation before the order is placed.

Where a guaranteed material grade, certification or traceability is required, KI Metals may need to source suitable material specifically against the customer’s written requirements.

Galvanising Process and Cut-End Protection

Galvanised Steel Box Section is normally cut to the required length before hot-dip galvanising. Each pre-cut length will usually include an approximately 8 mm process hole to allow safe venting and drainage during the galvanising process.

In some cases, material may be galvanised in full lengths and cut afterwards to avoid unnecessary process holes in smaller finished pieces. Where this method is used, the exposed cut ends are protected with a suitable zinc-rich cold galvanising spray.

If zinc-rich cold galvanising spray is not permitted for your project, or you require the cut ends to be hot-dip galvanised, please contact KI Metals before placing your order. We can review the cutting and galvanising requirements and confirm the most suitable production method.

Surface Condition

Galvanised Steel Box Section is supplied with a protective hot-dip galvanised zinc coating. The appearance of the finish may vary between sections and production batches.

Normal characteristics can include differences in colour or brightness, visible zinc spangle, drainage marks or runs, handling and storage marks, small areas of surface roughness, and variations around weld seams, corners and drainage points. These cosmetic variations are normal features of hot-dip galvanised steel and do not necessarily indicate a fault with the product or coating.

Corrosion Protection

The hot-dip galvanised zinc coating forms a protective barrier over the steel and provides improved resistance to atmospheric corrosion compared with untreated mild steel.

The service life of the coating depends on exposure conditions, environment, moisture or chemical contact, installation, maintenance and any later cutting, drilling, grinding or welding. Areas exposed or damaged after delivery through further fabrication should be protected with a suitable zinc-rich repair coating where continued corrosion resistance is required.

Typical Applications

• Gates and fencing
• Outdoor frames and supports
• Agricultural structures and equipment
• Sign frames
• Security barriers and bollards
• Shelving and storage frames
• Building and construction projects
• Garden structures
• Trailer and vehicle fabrication
• General engineering, maintenance and fabrication

Suitability for any load-bearing or safety-critical application should be confirmed by a suitably qualified engineer.

Custom Cut to Your Required Length

Enter your required measurement in the Length box before adding the product to your basket. We will cut the material to your specified length with a cutting tolerance of ±3 mm. The ordered quantity refers to the number of individual cut lengths required.

Customise Your Product

Depending on the selected product and available services, you may be able to add drilling instructions, upload a hand sketch or engineering drawing, request additional fabrication, or select available finishing options. Please provide clear measurements and instructions when ordering customised work.

Also Known As

• Galvanised Box Section
• Galvanised Rectangular Box Section
• Galvanised Hollow Section
• Galvanised Steel Tube
• Zinc-Coated Box Section
• Galvanised Mild Steel Box Section

Can Galvanised Box Section Be Welded?

Galvanised steel can be welded, but it should not be welded in the same way as untreated mild steel without appropriate preparation. The zinc coating should be removed from the immediate weld area before welding.

Heating zinc can produce hazardous zinc oxide fumes, so suitable ventilation, local fume extraction and appropriate personal protective equipment must be used. After welding, the affected area should be cleaned and treated with a suitable zinc-rich repair coating where corrosion protection is required.

KI Metals does not recommend welding galvanised products without the correct equipment, preparation, training and safety controls.

Frequently Asked Questions

Why is there an 8 mm hole in the section?

An approximately 8 mm process hole may be required to allow safe venting and drainage during hot-dip galvanising. This is a normal production feature and is not a product defect.

For some cutting requirements, the material may instead be galvanised in full lengths and cut afterwards, helping avoid a process hole in each smaller finished piece. Any exposed cut ends are then protected with zinc-rich cold galvanising spray.

If this repair method is not acceptable for your application, please contact KI Metals before ordering so that alternative galvanising arrangements can be discussed.

Can Galvanised Steel Box Section be used outdoors?

Yes. The zinc coating provides improved resistance to atmospheric corrosion, making it suitable for many outdoor applications. Service life depends on the environment, installation and maintenance.

Can it be cut to my required length?

Yes. Enter your required length on the product page before adding the item to your basket. We will cut it within our stated tolerance.

Will every piece have the same appearance?

Not necessarily. Variations in colour, brightness, spangle and surface texture are normal characteristics of galvanised steel.

Can Galvanised Box Section be drilled?

Yes. It is suitable for drilling and general fabrication using appropriate tools and working methods. Newly exposed areas may require additional corrosion protection.

Can it be painted?

Yes, but the galvanised surface must be cleaned and prepared correctly. Use primers and paint systems specifically suitable for galvanised steel.

Is a particular steel grade guaranteed?

No. Galvanised Steel Box Section is commonly supplied in S235JRH structural hollow section grade to BS EN 10219. Selected sections may be supplied in S355J2H structural hollow section grade to BS EN 10219 where applicable, depending on section size, supplier and current stock availability.

If a specific grade, certification or traceability is required, please contact KI Metals before ordering and obtain written confirmation from KI Metals. Telephone or verbal discussions, order notes and notes included with drawings do not constitute confirmation of supply requirements.

Safety Notice

This product is supplied as cut and is not deburred. Cut ends and edges may be sharp. Wear suitable protective gloves and appropriate personal protective equipment during handling, fabrication and installation.

Take particular care when cutting, grinding or drilling galvanised steel. Use suitable extraction and respiratory protection where dust or fumes may be generated.

Welding galvanised steel can produce hazardous zinc oxide fumes. The zinc coating must be appropriately removed from the weld area, and suitable ventilation, fume extraction and personal protective equipment must be used.