Steel Square Bar Manufacturer & Supplier – Sino East Steel Group
Sino East Steel Group has manufactured and exported steel square bars from our production base in Tianjin, China, since 2008. As a factory-direct supplier, we supply carbon steel square bars, stainless steel square bars, and bright drawn square bars straight from our own rolling, drawing, and finishing lines, with no trading intermediaries and no hidden margins. Our export team has delivered square bar steel to buyers in more than 80 countries across Asia, Africa, Europe, the Middle East, and the Americas. Stock sizes are available from a minimum order of just 5 tons, custom and drawn production starts at 20 tons, and standard delivery takes 15–30 days from Tianjin Xingang Port.
Square bars are prized by machinists, fabricators, and builders for their clean geometry, uniform cross-section, and predictable material properties. Our square bar is available in hot-rolled, cold-drawn, and bright finish forms, with side dimensions from 10 mm to 200 mm and standard lengths of 6 m and 12 m. Our annual production capacity for bars exceeds 100,000 tons, and each batch is traceable from raw billet to finished bundle. Whether your project calls for ASTM A36 structural stock, ASTM A276 stainless, or EN 10060 bright bar for precision machining, we deliver consistent, certified material at wholesale factory prices.
Why Choose Sino East Steel Group as Your Steel Square Bar Supplier?
International buyers choose Sino East Steel Group as their square steel bar supplier because we offer the combination that matters most in this product category: tight dimensional control, certified material grades, and genuine factory pricing. With nearly three decades of steel export experience, we understand what machine shops and structural contractors need, and we build our production and inspection routines around those needs. Here is what you can expect on every order.
1. Factory-Direct Manufacturing, No Middlemen
We own the rolling mill, drawing machines, straightening equipment, and surface finishing lines that produce your square bars. Because there is no trading company between you and the mill, you pay the factory price and communicate directly with the engineers who control quality and scheduling. Every inquiry is handled by our in-house export team, and every production order is booked on our own rolling and drawing plan, so delivery dates are commitments we can actually keep.
2. Full International Standards Compliance
Our square bars are manufactured and tested to ASTM A36, ASTM A276 for stainless grades, EN 10060 for drawn bars, and GB/T 702 for hot-rolled sections. Chemical composition, mechanical properties, surface condition, and dimensional tolerances are verified against the applicable standard before release. Each shipment is accompanied by mill test certificates in EN 10204 3.1 format, and we can provide third-party inspection reports with heat-number traceability when your project requires them.
3. Stable Quality with Multi-Step Inspection
Quality control begins with incoming billet analysis and continues through rolling, drawing, straightening, cutting, and surface inspection. We measure side dimensions, corner radii, straightness, and surface finish with calibrated instruments at regular intervals, and our laboratory verifies hardness, tensile strength, and chemical composition for each production lot. This disciplined approach keeps our customer-arrival rejection rate below 0.5 percent, and our written quality guarantee covers every order we ship.
4. Flexible Supply for All Project Scales
Whether you need a 5-ton lot of stock sizes for a job shop or a 1,500-ton allocation for a national construction program, we can supply it. Popular sizes are held in stock for fast dispatch, while custom sections, longer lengths, bright drawn finishes, and tight tolerance requirements are produced to order. We also support mixed-container orders, so you can combine square bars with flat bars, angles, pipes, and other products in a single shipment to save freight.
Steel Square Bar Product Range
Our square bar program covers three main product families, each available across a wide range of sizes and finishes. Describe your application or send your drawing, and our engineers will recommend the most cost-effective grade and production route for your requirement.
Carbon Steel Square Bar (A36 / Q235 / Q345)
Carbon steel square bar is the standard choice for structural bracing, general fabrication, and parts that will be machined or welded. It is supplied hot-rolled in grades A36, Q235, and Q345, with side dimensions from 10 mm to 200 mm and lengths of 6 m or 12 m. The material welds and machines predictably, and it is available in black, bright, or painted surface finishes. For higher strength requirements, Q345 offers improved yield performance for frames and load-bearing members.
Stainless Steel Square Bar (304/316)
Stainless steel square bar in grades 304 and 316 combines clean geometry with excellent corrosion resistance for marine hardware, food processing equipment, chemical plant components, and architectural fittings. We supply hot-rolled and cold-finished stainless square bars with pickled, bright, or polished surfaces. Grade 316 is recommended for coastal and chloride-rich environments, while grade 304 covers most general industrial uses. Each stainless bar carries full material certification, and surface quality is verified piece by piece before packing.
Bright Drawn Square Bar
Bright drawn square bar is produced by cold drawing hot-rolled bar through a die, which improves dimensional accuracy, surface finish, and mechanical properties. Tolerances are considerably tighter than hot-rolled bar, typically H9 to H11, and the bright surface reduces machining stock and finishing time in your workshop. It is ideal for shafts, pins, guide rails, fasteners, and precision components that go straight to machining. We supply bright drawn bar in carbon and stainless grades, in sizes from 10 mm to 100 mm.
Steel Square Bar Specifications
The table below summarizes the standard size range and specifications for our steel square bars. Non-standard sections can be produced subject to rolling or drawing program confirmation, so please send your exact requirement for a firm quotation.
| Parameter | Available Range |
|---|---|
| Material Grade | A36 / Q235 / Q345 (carbon); 304 / 316 (stainless) |
| Side Dimension | 10 – 200 mm |
| Length | 6 m / 12 m (cut-to-length available) |
| Production Form | Hot-rolled / Cold-drawn / Bright finish |
| Standards | ASTM A36 / ASTM A276 / EN 10060 / GB/T 702 |
| Surface Finish | Black / Bright / Polished / Painted |
| Straightness | Per applicable standard, improved for drawn bars |
| Packing | Hexagonal bundles with steel straps |
| Certification | Mill test certificate, EN 10204 3.1, third-party inspection |
Square Bar Dimension and Weight Reference Table
Theoretical weight is calculated as side × side × 0.00785 kg/m, based on a steel density of 7.85 g/cm³. Actual bundle weights may vary slightly with rolling tolerances; invoicing is based on weighbridge weight at loading.
| Section (Side × Side) | Theoretical Weight (kg/m) |
|---|---|
| 10 × 10 mm | 0.79 |
| 16 × 16 mm | 2.01 |
| 20 × 20 mm | 3.14 |
| 25 × 25 mm | 4.91 |
| 32 × 32 mm | 8.04 |
| 40 × 40 mm | 12.56 |
| 50 × 50 mm | 19.63 |
| 60 × 60 mm | 28.26 |
| 80 × 80 mm | 50.24 |
| 100 × 100 mm | 78.50 |
Typical Applications of Steel Square Bar
Steel square bars are used wherever designers need a strong, straight, machinable section with clean geometry. Typical applications include:
- Machine shafts, axles, pins, and drive components
- Jigs, fixtures, tooling, and press brake tooling stock
- Structural bracing, frames, and support columns in steel buildings
- Handrails, balustrades, gates, and architectural detailing
- Fastener and key stock for mechanical assemblies
- Dowels, anchors, and embedded items in concrete work
- Furniture frames and decorative metalwork
- Trailer, truck, and agricultural equipment components
Precision Cross-Section, Delivered Consistently
The value of a square bar lies in its geometry: four flat faces, sharp or slightly rounded corners, and a cross-section that does not wander along the length. Our rolling stands are set to tight tolerances, drawn bars pass through precision dies, and straightening rolls remove any residual bow before cutting. We check the section with micrometers at both ends and the middle of each bar, and we verify surface quality under good lighting so scratches, seams, and rolled-in scale are caught at the mill rather than at your machine. For bright drawn material, we also confirm diameter-over-corners and corner radius so your collet, chuck, or broaching setup works first time. This attention to detail is why machine shops across 80 countries reorder from us year after year.
How We Ensure Reliable Export Service
Nearly three decades of exporting steel has taught us that reliable service is about documentation, communication, and packing as much as it is about price. Here is how we protect every square bar shipment from our factory to your warehouse.
Export Experience Across 80+ Countries
We ship steel square bars to more than 80 countries every year, covering Southeast Asia, the Middle East, Africa, Europe, and the Americas. We know the documentary requirements, port practices, and packing preferences of each region, and we apply that knowledge to every order, from single-container lots to large project allocations. Your local agent or customs broker will find our paperwork consistent and complete.
Professional Export Documentation
Every shipment includes a commercial invoice, packing list, bill of lading, certificate of origin, and mill test certificates with chemical and mechanical data. Where projects require independent verification, we arrange SGS, BV, or TÜV inspection before loading and provide loading supervision reports with photographs and weighbridge tickets. Special documents such as EUR.1, Form A, or pre-shipment quality certificates can be prepared on request.
Flexible Payment and Incoterms
We quote FOB Tianjin as standard and can also provide CIF, CFR, and DDP pricing to almost any destination. Payment terms are T/T with a 30 percent deposit and 70 percent balance against shipping documents, or L/C at sight for established accounts. For repeat buyers we can discuss more flexible settlement arrangements, and for urgent projects we will always tell you honestly which dates we can commit to.
Pricing, MOQ & Delivery
The summary below explains how we price and schedule square bar orders. Firm quotations depend on grade, size, finish, quantity, and current raw material markets, so please send your specification for an exact price.
- Price range: USD 520–1100 per ton FOB Tianjin, depending on grade, size, and finish
- MOQ: 5 tons for stock sizes; 20 tons for custom, drawn, or cut-to-length production
- Payment: T/T 30% deposit plus 70% against shipping documents, or L/C at sight
- Delivery: 15–30 days after deposit confirmation, depending on size and quantity
- Packing: hexagonal bundles with steel straps, waterproof inner wrapping for ocean freight
Buyer’s Guide: How to Choose a Reliable Steel Square Bar Supplier
A dependable square steel bar supplier is defined by traceability and tolerance control. First, confirm that mill test certificates are issued for your actual heat numbers, not generic templates, because grade verification protects your downstream certification. Second, agree on dimensional tolerances in writing, especially for drawn bars where H-grade tolerances are critical for machining. Third, compare the cost of the finished part, not just the price per ton, because better straightness and surface finish save machining time and tool wear. Fourth, check the supplier’s packing and marking practices, since mixed or unmarked bundles create chaos in your warehouse. Finally, choose a factory you can visit or audit, and test them with a first small order before committing to large volumes.
How to Get a Quotation
Requesting a square bar price from Sino East Steel Group is straightforward. Send us the grade, side dimension, length, surface finish, quantity, and destination port, and our export team will respond within 24 hours with a complete offer covering unit price, delivery time, packing, and documentation. If you are comparing options between hot-rolled and bright drawn bar, tell us how the bar will be used and we will recommend the most economical solution. Contact us through the form on this page, by email, or by phone and WhatsApp, and our engineers will be happy to answer technical questions.
Frequently Asked Questions (FAQ)
Q1: What is the difference between hot-rolled and bright drawn square bar?
Hot-rolled square bar is formed at high temperature directly from the rolling mill, so it has a black mill scale surface and standard rolling tolerances, which makes it economical for structural and general fabrication. Bright drawn square bar is hot-rolled bar that is cold drawn through a die, giving a clean bright surface, tighter dimensional tolerances, and slightly higher strength. Choose hot-rolled for framing and welding work, and bright drawn for machined parts, shafts, and components that need accurate dimensions and a smooth finish.
Q2: How do you calculate the weight of a steel square bar?
The theoretical weight is calculated as side dimension in millimeters multiplied by itself, then multiplied by 0.00785, which gives kilograms per meter. For example, a 50 mm square bar weighs 50 × 50 × 0.00785 = 19.63 kg/m. Multiply by the length to get the weight per bar, and remember that actual shipment weight is based on weighbridge tickets, which may differ slightly from theoretical values because of rolling tolerances.
Q3: Can you supply square bars for precision machining with tight tolerances?
Yes. For machining applications we recommend bright drawn square bar, which we supply to H9–H11 tolerance classes with verified straightness and corner radius. We can also provide centerless-ground or cold-finished material for demanding applications, subject to size and quantity. Send us your drawing with the required tolerance class and surface finish, and we will confirm the best production route and price.
Q4: Which stainless steel grade should I choose for square bar?
Grade 304 is the general-purpose choice for food processing, chemical, and architectural applications where corrosion resistance and easy cleaning matter. Grade 316 adds molybdenum for superior resistance to chlorides, seawater, and industrial chemicals, making it the right choice for marine hardware, coastal construction, and offshore equipment. If you need higher strength or special properties, we can also source duplex and other grades on request.
Q5: Can I combine square bars with other steel products in one container?
Yes, mixed-container loading is one of our specialties. You can combine square bars with flat bars, angles, channels, pipes, and other sections in a single shipment, which reduces freight cost per ton and simplifies customs clearance. Our loading team balances bundle weights and arranges dunnage so the container remains stable and safe in transit, and we provide a detailed packing list for every mixed load.
Q6: How is square bar marked and packed for export?
Each bundle is marked with size, grade, heat number, and bundle weight using durable tags and paint markings. Bars are packed in hexagonal bundles secured with steel straps, wrapped in waterproof material for ocean voyages, and loaded with proper dunnage in the container. This marking system lets your warehouse staff identify material instantly and keeps your quality records traceable from our mill to your finished product.
Contact Sino East Steel Group today – send us your square bar requirement and receive factory-direct pricing, certified grades, and dependable export service from a manufacturer trusted in 80+ countries. Our team is ready to help you source the right steel square bars for your next project.