What materials and grades do you supply?

We supply Carbon Steel grades including Q235, Q345, St37, St52, St37-2, 20#, and 16mn.

What are the main applications for these pipes?

They are widely used in construction, machinery industry, scaffolding, furniture, low-pressure fluid pipes, and boiler pipes.

What is the production capacity?

Our productivity is 6000 Metric Tons per Month.

Black Iron Pipe Cold Rolled Mild Steel Iron Square Pipe Carbon Rectangular Steel Tube

Name: Black Iron Pipe Cold Rolled Mild Steel Iron Square Pipe Carbon Rectangular Steel Tube
Brand: LIAOCHENG HUAJIAN STEEL CO., LTD.
SKU: 2082164182

Shandong, ChinaLIAOCHENG HUAJIAN STEEL CO., LTD.

US$550.00-650.00

10 Tons

Sample price:US$0.00/piece.Request sample

Product profile

Customization

Available

Type

Welded

Technique

ERW

Material

Carbon Steel

Surface Treatment

Galvanized

Usage

Pipeline Transport, Hydraulic/Automobile Pipe, Food/Beverage/Dairy Products, Machinery Industry, Chemical Industry, Mining, Construction & Decoration, Special Purpose

Section Shape

Square

Shape

Square Pipe

Grade

Q235 Q345 St37 St52 St37-2 20# 16mn

Surface

Black, Paint, Galvanized

Outer Diameter

10*10~1000*1000mm

Thickness

0.5-50mm

Application

Structure Pipe, etc

Packing

in Bundles

Delivery Time

Within 15~20 Days

Sample

Avaliable

Transport Package

Standard Export Sea-Worthy Packing

Specification

100*100*10

Trademark

HJ steel

Origin

Shandong Province, China

Production Capacity

5000tons Per Month

Key features

Wide Size Range: Outer diameter 10*10-1000*1000mm, thickness 0.5-50mm, length 4m-14m.

Multiple Surface Options: Available in Black, Paint, and Galvanized finishes with zinc coating 60-400g/m2.

Extensive Material Grades: Supports Q235, Q345, St37, St52, 20#, 16mn, and other carbon steel grades.

Flexible Customization: Custom shapes, sizes, and surface treatments available based on customer requirements.

Strict Quality Control: Inspection via hydraulic testing, eddy current, infrared, and ISO9001:2000 compliance.

Fast Delivery Options: Stock items ship in 7-10 days; custom orders delivered within 15-30 days.

Versatile Applications: Suitable for construction, machinery, scaffolding, furniture, and pipeline transport.

Competitive Pricing: Low ex-factory prices due to large stocks and long-term cooperative factories.

Company profile

Importers and ExportersHigh Repeat Buyers ChoiceYears of Export ExperienceExhibition Experience

LIAOCHENG HUAJIAN STEEL CO., LTD.

Shandong, China

Business Type: Manufacturer/Factory, Trading Company CertifiedR&D Capacity: ODM Service Available & OEM Service Available CertifiedCustomization Options: Customization from Samples, Customization from Designs, etc. CertifiedExport Year: 12 years CertifiedNearest Port: Qingdao Port, Tianjing PortAverage Response Time: ≤10.75h

AI-Powered supplier vetting

SummaryThe supplier is identified as a professional technical supplier with broad customization, 3D software design, ODM, OEM, and recent new-product development capabilities. It reports substantial steel plate and H-beam output, inventory capability, overseas warehouse services, overseas agents or branches, and direct import-export rights. Export activity represents 90% of total sales, with Europe and North America listed as primary markets and 12 years of export experience. Service procedures exist for corrective and preventive actions and complaint handling, with follow-up records. Financial records are referenced for 2021–2023, but their actual results are not provided. Certification, manufacturing-contract status, environmental compliance, fire-drill status, and formal supplier-service assessment procedures remain insufficiently documented.

Supplier typeThe supplier is explicitly described as a professional technical supplier, with steel plate and H-beam production, direct import-export rights, and Europe and North America identified as primary export markets. Its export share is stated as 90%, and it has 12 years of export experience, indicating a technically oriented and internationally active manufacturing supplier.

After-Sales capabilityThe supplier has clear procedures and follow-up records for corrective and preventive actions and customer complaints. It also reports inventory capability, overseas warehouse services, overseas agents or branches, and participation in the 2023 MTM offline trade show; however, there is no overseas showroom and the number of countries served overseas is recorded as 0.

R&D capabilityThe supplier provides 3D software design services, supports multiple forms of customization, reported new products within the past year, and offers ODM services. It has no available SDK, which limits the evidence for software-development integration capability but does not negate its documented product and design innovation capabilities.

Production capacityThe supplier reports annual production information of 50,000 tons of steel plate and 50,000 tons of H-beam, 21–30 quality-control staff, in-stock capability, and lead times within 15 working days in both peak and off-seasons. A valid manufacturing-capacity contract is unknown, so contractual validation is incomplete, but the stated operating capabilities support a positive assessment.

Customization capabilityThe supplier explicitly offers customization from samples, designs, full customization, minor customization, and flexible customization, together with 3D software design, ODM, and OEM services for well-known brands. This combination demonstrates broad documented customization coverage.

Client casesThe supplier reports OEM services for well-known brands and participation in the 2023 MTM offline trade show. These are relevant customer or market-experience indicators, but no customer names, project details, order outcomes, or verifiable case descriptions are supplied.

Product Q&A

Q:What is the minimum order quantity?

The minimum order quantity is 15 Metric Tons.

Q:What are the payment terms?

We support T/T and 100% L/C at sight.

Q:How long is the delivery time?

For normal sizes with stock, shipment is within 7-10 days after deposit. For custom orders, delivery is within 25-30 days after receiving the deposit.

Q:Do you charge for samples?

No, we provide samples for free; the buyer only needs to pay for the freight charge.

Q:What surface treatments are available?

Available surface treatments include Black, Paint, and Galvanized (Pre-galvanized or Hot-dipped galvanized).