Products

DESCRIPTION

• Overview
• PRODUCT INTRODUCTION
• MAIN PRODUCT
• Company Profile
• CORPORATE ADVANTAGE
• OUR CERTIFICATE
• CUSTOMER VISIT
• FAQ

Overview

Basic Info.

Model NO.	Hot-dip galvanized rectangular steelpipe
Type	Non-Alloy
Technique	Hot Rolled
Material	Carbon Steel
Surface Treatment	Galvanized
Usage	Construction & Decoration, Curtain Wall Supports Steel Structure Workshops
Section Shape	Rectangular
Thickness	1.5mm-30mm
Alloy	Non-Alloy
Tolerance	Standard
Delivery Time	5 to 25 Days
Length	Customized Length
Transportation	Bulk Vessel, Container Shipment
Steel Grade	Gr.a/B/C/D, S195jr, S235jr, S275jr, S355jr, S355j0
Process	Cutting Welding Bending
Transport Package	Standard Export Packaging
Specification	15-1000mm
Trademark	Huatuo
Origin	Tianjin, China
Production Capacity	400, 000ton/Year

Product Description

PRODUCT INTRODUCTION

Our Hot-dip Galvanized Rectangular Steel Pipe, made in Tianjin, China under the Huatuo brand, is a top-tier carbon steel product for structural use. Made from premium non-alloy carbon steel with grades like Gr.A/B/C/D, S195jr, S235jr, S275jr, S355jr, S355j0, S355j2, S460jr, and S600jr, this pipe offers outstanding load-bearing capacity and durability for demanding structures.
With a specification range of 15-1000mm in rectangular section and thickness from 1.5mm to 30mm, all products meet standard tolerances for consistent quality, allowing easy integration into various projects. The hot-dip galvanizing surface treatment provides superior corrosion and wear resistance, extending service life even in challenging environments. We offer flexible services including cutting, welding, and bending, and support customized lengths to meet diverse customer needs.This versatile Hot-dip Galvanized Rectangular Steel Pipe is used in building structures & curtain wall supports, steel workshops & warehouses, and storage racks & logistics shelving. Its thickness range of 1.5mm-30mm and 15-1000mm specification meet the requirements of large-scale projects. With a strong annual production capacity of 400,000 tons, we ensure a stable supply and delivery time of 5 to 25 days for urgent timelines.
For transport and packaging, we use standard export packaging to protect products during transit, offering two shipping methods: bulk vessel and container shipment, catering to various order volumes globally. Whether for high-rise building supports, industrial structures, or storage racks, our Huatuo Hot-dip Galvanized Rectangular Steel Pipe is a durable, cost-effective choice for structural projects..

Thickness	1.5mm-30mm	Surface Treatment	galvanized
Alloy	Non-alloy	Product Name	Hot-dip galvanized square steel pipe
Section Shape	rectangular	Tolerance	Standard
Delivery Time	5 to 25 days	Application	Building structures & curtain wall supports Steel structure workshops & warehouses Storage racks & logistics shelving
Length	customized length	Transportation	Bulk Vessel,Container Shipment
Transport Package	standard export packaging	Trademark	Huatuo
Origin	Tianjin, China	Production Capacity	400,000ton/Year
steel grade	Gr.a/B/C/D,S195jr,S235jr,S275jr, S355jr ,S355j0,S355j2,S460jr, S600jr	Specification	15-1000mm
process	cutting welding bending	material	carbon steel

MAIN PRODUCT

Company Profile

Zhejiang Huatuo Metal Materials Co., Ltd. is located in the Deqing International Steel Trade City with convenient transportation. Through years of relentless efforts, the company hasdeveloped into a large-sized enterprise integrating steel trading, galvanizing processing,and logistics distribution. Boasting over 16,000square meters of large-scale indoor ware-houses, we maintain long-term and stable strategic cooperative relationships with numer-ous landmark domestic steel mills, including Tianjin Yuantai, Tianjin Youfa Group, andHandan Zhengda Pipe Manufacturing. Our regular inventory stands at 20,000 tons.With 30 years of development, the company has grown into a large-sized steel trading en-terprise in Hangzhou, widely recognized by customers. We have established long-term co-operative partnerships with local well-known enterprises such as Zhejiang Yasha Group andSoutheast Steel Structure.In 2024, the company achieved a major breakthrough in totalsales volume,exceeding 380,000 tons.
Guided by the core values of ".Professionalism, Integrity, and Trustworthiness, the companyhas gained consistent recognition and praise from agents and end customers over theyears,earning an outstanding business reputation. For more than a decade, adhering to acustomer-centric approach, we have not only focused on market development in Hangzhouand its surrounding areas but also established sound cooperative partnerships with agentsand end customers across Zhejiang Province. Our high-quality and dedicated services havewon the trust and acclaim of numerous enterprises, gradually building a strong brand imagein Hangzhou and the neighboring regions.

CORPORATE ADVANTAGE

OUR CERTIFICATE

CUSTOMER VISIT

FAQ1. What are the applications and acceptance criteria of hot-dip galvanized steel pipes?
Answer: From the current application scope, hot-dip galvanized steel pipes are widely used in key fields such as curtain walls, power transmission towers, and communication & power grids. In recent years, they have gained widespread adoption across various regions and industries—fully demonstrating their excellent quality and practical convenience in usage, which ensures reliable and efficient performance in real-world applications.
2. What are the acceptance criteria for hot-dip galvanized steel pipes?
Answer: During project acceptance, hot-dip galvanized steel pipes can be judged qualified by checking their appearance. Specifically, inspect the entire surface for defects such as missing plating or bubbles. Only when these issues are promptly addressed can the product be deemed qualified, ensuring its reliable application in subsequent projects.
3. Why do hot-dip galvanized steel pipes still rust despite being galvanized?
Answer: The main reason for the rusting of hot-dip galvanized steel pipes lies in the zinc coating on their surface. Zinc is chemically active—it dissolves in both acids and alkalis. In humid environments, zinc undergoes chemical reactions to form a basic zinc carbonate film on the surface. However, when in contact with substances containing hydrogen sulfide, zinc's corrosion resistance decreases significantly, making it prone to corrosion. Once the zinc coating is corroded, the underlying steel plate is exposed, leading to subsequent rusting. Galvanized steel coils processed by phosphating treatment have a relatively low risk of rusting. This is because the phosphating coating is thicker, which effectively prevents the steel plate from oxidizing and thus inhibits rust formation.
4. How to avoid cracking when welding square and rectangular steel pipes in low-temperature environments?
Answer: Prioritize low-hydrogen welding materials (dried beforehand). Preheat (80-200℃) based on material/wall thickness before welding. Adopt symmetric welding and control interpass temperature during operation. Insulate and cool slowly for ≥2 hours post-welding. Avoid rapid cooling and stress concentration; conduct stress relief testing for critical welds.