Sihe Steel
Sihe Steel
Explore our top industrial-grade tubing solutions engineered for subsea, pharmaceutical, and high-temperature systems.
As a premier developer and manufacturer operating from Shandong, China, Liaocheng Sihe Stainless Steel Material LTD is a leading expert in the production of high-performance stainless steel coiled tube, stainless steel polishing tube, and seamless coiled tubing. Armed with multiple production lines and a highly specialized metallurgical division, we strictly execute production standards in alignment with GB, ASTM, ASME, JIS, and EN requirements.
Our material portfolio spans standard austenitic alloys such as 304/304L, 316L, 321, 317L, 309S, 310S to specialized duplex grades including Incoloy 800, Austenitic steel 316L, Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625. We engineer structural profiles ranging in outer diameter from 0.125 inches (3.175 mm) to 1 inch (25.4 mm) with wall thicknesses up to 0.165 inches (3 mm). Continuous, weld-free spooled lengths up to 32,800 feet (10,000 meters) are made available for subsea umbilical control systems and industrial instrumentation modules.
As global energy operations move to deep waters and extreme processing environments, the demand for corrosion-resistant, high-strength tubing material has grown exponentially. Our focus lies in providing optimal coiled umbilical tubing that meets mechanical stress and chemical tolerance requirements in these offshore environments.
Liaocheng Sihe has built an export footprint spanning over 30 countries and regions, including the US, Germany, Spain, South America, Southeast Asia, the Middle East, and Eastern Europe. Approximately 80% of our high-precision coils are exported globally, supported by advanced bright annealing treatment lines that enable online softening to ensure consistent mechanical ductility and surface finish.
Witness the operational scale of our Chinese facility, incorporating inline bright annealing and automated cold drawing systems.
Our heavy-duty drawing machinery applies precision sizing to coiled tubes, optimizing wall uniformity and preventing thickness variations. This provides structural integrity required for high-pressure control lines.
Continuous coiled tubes are spooled on heavy-duty drums. This design minimizes orbital field welding requirements, reducing potential leak paths across long-distance distribution networks.
A deep metallurgical analysis of performance characteristics, microstructural control, and manufacturing pathways.
Type 304 stainless steel represents the classic 18-8 austenitic alloy family. At the molecular level, its alloy composition is controlled to maintain a stable austenitic structure at low and high temperatures:
Cold working during continuous drawing increases yield strength but reduces elongation properties. To restore the required ductility, Sihe utilizes online bright annealing (BA) technology:
The tubing is heated to 1040°C - 1150°C within a controlled, dry hydrogen atmosphere. This process dissolves precipitated carbides back into the solid solution without exposure to oxygen. The result is a clean surface finish on the outer and inner diameters, eliminating the need for post-heat-treatment chemical pickling.
To verify reliability across demanding applications, each run of coiled tubing undergoes a comprehensive quality check:
How 304 and alternative alloy coiled tubing designs serve critical systems across industries.
Subsea control systems rely on hydraulic fluid transmission through continuous umbilical assemblies. Our coiled tubing provides the required fatigue resistance to withstand cyclic ocean currents and high external pressures. By selecting corrosion-resistant alloys like Incoloy 825 or Inconel 625, offshore operators can reduce the risk of localized pitting and stress-corrosion cracking (SCC) in chloride-rich environments.
For gas delivery systems in semiconductor cleanrooms and pharmaceutical facilities, internal surface roughness is a key parameter. Our bright-annealed and polished 304 and 316L capillary lines feature highly smooth internal surfaces. This prevents moisture entrapment and particulate contamination, meeting high-purity standards.
Downstream fabrication capabilities supporting mechanical and thermal configuration needs.
We support various materials (e.g., 304, 316L, 2205) and custom specifications, offering diameter ranges from 6.35mm to 19mm for stainless steel coils.
Includes bending, spiral forming, and precision drawing, designed specifically for heat exchanger applications.
We utilize laser cutting, mechanical cutting, and flame cutting methods to deliver clean, precise cuts with tight tolerances.
Our facility incorporates polishing and pickling systems to finish outer and inner surfaces, meeting specific surface requirements.
Commonly used in automotive exhaust systems, chemical pipelines, and precision instrument connections to secure leak-free joints.
Sihe coiled and straight tubes are utilized in many systems worldwide.
Documented validation of our manufacturing protocols and quality assurance standards.
Every shipment from Liaocheng Sihe is accompanied by comprehensive certifications, including EN 10204 3.1 Material Test Certificates (MTC), which provide full traceability from the raw steel heat number down to the final coiled product. Our quality management system conforms to ISO standards, ensuring consistent tolerances across production runs.
Our documentation suite includes:
Our factory in Shandong leverages local raw material supply chains to secure consistent steel feedstock and mitigate price volatility. We use reinforced packaging, including heavy-duty wooden spools, steel reels, and moisture-barrier wrap, to protect the tubing during international transport. Our logistics teams handle the necessary steps for shipping dangerous or sensitive cargo safely.
Understanding cost structures, material selection, and optimization options for international purchases.
As 304 and 316L contain significant quantities of nickel (Ni) and chromium (Cr), the pricing of raw materials is linked to London Metal Exchange (LME) price fluctuations. Sourcing during favorable market cycles can help optimize material acquisition costs.
Longer continuous lines require careful monitoring of wall thickness and consistency during draw cycles. Continuous spools without welds command premium pricing compared to welded segments but offer greater reliability for subsea or high-pressure installations.
Proper packaging, such as metal spools or specialized wooden reels, is essential to protect thin-walled tubing from deformation during transit. The choice of packaging depends on the delivery method, shipping duration, and installation requirements.
Answers to common questions regarding specifications, logistics, and procurement processes.
Our prices are subject to change depending on supply and other market factors. We will send you an updated price list after your company contacts us for further information, outlining custom sizes, lengths, and grades.
Yes, we require all international orders to have an ongoing minimum order quantity. If you are looking to resell but in much smaller quantities, we recommend you check out our website for smaller custom orders or local distributor listings.
Yes, we can provide most documentation including Certificates of Analysis / Conformance; Insurance; Origin, and other export documents where required. All shipments are traceable back to the raw material melt.
For samples, the lead time is about 7 days. For mass production, the lead time is 20-30 days after receiving the deposit payment. The lead times become effective when (1) we have received your deposit, and (2) we have your final approval for your products. If our lead times do not work with your deadline, please go over your requirements with your sales representative.
You can make the payment to our bank account, Western Union or PayPal: 30% deposit in advance, 70% balance against the copy of B/L.
We warranty our materials and workmanship. Our commitment is to your satisfaction with our products. In warranty or not, it is the culture of our company to address and resolve all customer issues to everyone’s satisfaction.
Yes, we always use high quality export packaging. We also use specialized hazard packing for dangerous goods and validated cold storage shippers for temperature sensitive items. Specialist packaging and non-standard packing requirements may incur an additional charge.
The shipping cost depends on the way you choose to get the goods. Express is normally the quickest but also most expensive way. By sea freight is the best solution for large quantities. Exact freight rates can be provided once we confirm weight, volume, and destination port.
Browse our extended product catalog for specialized industrial applications, including heat exchanger and capillary systems.
