Sihe Steel
Sihe Steel
Explore our elite selection of high-performance alloy tubing manufactured strictly according to international standards.
An Industry Pioneer with 10 Years of Manufacturing History & Advanced Refining Production Lines
Based in China, Liaocheng Sihe Stainless Steel Material LTD stands at the forefront of precision steel metallurgy. We are a specialized, large-scale expert in producing high-quality stainless steel coiled tubes, stainless steel polishing tubes, and seamless coiled tubing. Utilizing world-class online bright annealing technology, we produce ultra-long seamless pipes up to 32,800 feet (10,000 meters) in a single continuous coil.
We maintain strict adherence to international production standards including GB, ASTM, ASME, JIS, and EN. Our capability extends to a diverse array of steel grades: 304/304L, 316L, 321, 317L, 309S, 310S, and high-performance super alloys such as INCOLOY 800, Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625.
As offshore oil and gas developments shift toward deeper and harsher waters, our mission remains critical: providing the correct corrosion-resistant material for coiled umbilical tubing to guarantee operational safety, mitigate failures, and ensure structural reliability.
Analyzing key advancements, metallurgical optimizations, and the shifts in high-purity industrial requirements.
The global transition to hydrogen energy requires pipeline infrastructure that resists hydrogen embrittlement. Seamless 316L tubing, with low carbon and controlled nickel content, provides the microstructure stability needed for high-pressure storage and distribution systems.
Subsea umbilicals operate in depths exceeding 3,000 meters. Structural integrity is critical in these environments. 316L seamless tubes provide high creep-rupture strength and high pitting resistance (PREN ≥ 23-25), preventing offshore chemical spills and costly pipeline failures.
Microelectronics manufacturing relies on clean-room grade gas delivery. Seamless tubing processed with online bright annealing guarantees an ultra-smooth internal surface (Ra ≤ 0.4 μm) and minimal particle shedding, meeting semiconductor fabrication standards.
Custom dimensions engineered to support heavy industrial operations and precise engineering requirements.
Our coiled and seamless stainless steel tubes are manufactured with high precision to meet tight engineering tolerances. Outside diameters range from 0.125 inches (3.175 mm) to 1 inch (25.4 mm). Wall thicknesses are available up to 0.165 inches (3.0 mm) depending on application requirements.
By using modern continuous cold-drawing and cold-rolling equipment, we can achieve single continuous coils up to 32,800 feet (10,000 meters). This reduces the need for orbital welding joints during field installation, minimizing risk points and reducing installer layout costs.
Comparing chemical compositions and properties to help procurement teams choose the correct steel grade for specific operating environments.
| Steel Grade / Alloy | UNS Designation | Cr (%) | Ni (%) | Mo (%) | Key Environmental Strength |
|---|---|---|---|---|---|
| Austenitic 304/304L | S30400/S30403 | 18.0 - 20.0 | 8.0 - 12.0 | - | General corrosion resistance; cost-effective instrumentation tubing. |
| Austenitic 316L | S31603 | 16.0 - 18.0 | 10.0 - 14.0 | 2.0 - 3.0 | High resistance to chloride pitting; ideal for marine and chemical systems. |
| Duplex 2205 | S31803 / S32205 | 21.0 - 23.0 | 4.5 - 6.5 | 2.5 - 3.5 | High yield strength; superior resistance to stress corrosion cracking (SCC). |
| Super Duplex 2507 | S32750 | 24.0 - 26.0 | 6.0 - 8.0 | 3.0 - 5.0 | Designed for harsh offshore oil/gas operations; high PREN rating. |
| Incoloy 825 | N08825 | 19.5 - 23.5 | 38.0 - 46.0 | 2.5 - 3.5 | Resists reducing/oxidizing acids and stress corrosion cracking. |
| Inconel 625 | N06625 | 20.0 - 23.0 | ≥ 58.0 | 8.0 - 10.0 | High temperature stability and extreme oxidation resistance. |
We provide full-process fabrication options tailored to demanding mechanical layout designs.
We custom process multiple steel grades (304, 316L, 2205) in diameters ranging from 6.35mm to 19mm to fit custom layout designs.
We perform precision tube bending and spiral forming, including long continuous coil configurations for heat exchanger installations.
We offer laser, mechanical, or flame cutting options to supply accurate tube lengths with clean, burr-free cuts.
We perform mechanical polishing, electropolishing, and passivation to meet critical purity standards.
We prepare tube ends with flanging and pre-flared profiles for use in automotive exhausts, chemical pipelines, and instrument manifolds.
Our stainless steel coiled tubing is utilized across many engineering fields and harsh environments.
We perform mechanical and non-destructive testing to verify that our tubing meets global engineering standards.
To verify the mechanical and dimensional stability of our products, we perform a complete series of tests on every production run:
We ship products directly to international ports, supporting logistics and customs clearance.
Liaocheng Sihe Stainless Steel Material LTD has exported products to over 30 countries and regions, including the United States, Germany, Spain, South America, Southeast Asia, the Middle East, and Eastern Europe. Over 80% of our production volume is exported to meet international client needs.
We work with global shipping lines to arrange ocean freight, air transport, and overland transport, helping to manage delivery timelines for large-scale engineering projects.
Our planned technical developments focus on cleaner alloys and improved surface treatment processes.
We are refining our melting processes to reduce trace elements, minimizing slag and oxide inclusions to increase structural strength under fatigue load.
We are developing polishing lines targeting an internal roughness of Ra ≤ 0.2 μm, supporting ultra-high purity gas delivery in microelectronics.
We are expanding our alloy production capacity for high-nickel, high-chromium, and molybdenum grades to handle high H2S and CO2 downhole environments.
We supply a broad range of products, from flexible coiled tubing to heavy structural plates.
Answers to common questions regarding our products, minimum order quantities, lead times, and payment terms.
Our prices are subject to change depending on supply, raw material costs, and global market factors. We will send you an updated price list after you contact us with details on your grade and dimension requirements.
Yes, we require all international orders to have an ongoing minimum order quantity. If you are looking to purchase smaller quantities for regional distribution, please reach out to check our current inventory.
Yes, we provide standard export documentation, including Certificates of Analysis (MTC / Mill Test Certificate EN 10204 3.1), Certificates of Conformance, Insurance, Certificates of Origin, and related logistics paperwork.
Sample production takes approximately 7 days. Mass production runs require 20 to 30 days after receiving the deposit payment. Lead times begin once deposit payment is received and technical design approvals are completed.
We accept bank transfers (T/T), Western Union, and PayPal. Our standard terms are a 30% deposit in advance, with the 70% balance paid against the copy of the Bill of Lading (B/L).
We provide a warranty covering material defects and workmanship. In the event of a quality issue, we work to evaluate and resolve the problem according to our standard warranty terms.
Yes, we pack all coiled and straight tubes in reinforced wooden crates or metal frames to prevent shifting and surface scratches during ocean transit. Special packaging requirements can be accommodated upon request.
Shipping costs depend on the delivery method, order weight, volume, and destination port. Sea freight is generally the most cost-effective solution for large volumes. Contact our sales department to request a freight quote.
Select specialized alloy tubing and connectors to meet high-pressure fluid handling requirements.
