Sihe Steel
Sihe Steel
Explore our high-performance capillary tubes, heat exchanger pipes, and coiled configurations designed for extreme operational environments.
In modern industrial engineering, demanding thermal environments require piping solutions that maintain structural integrity, resist oxidation, and prevent creep deformation. Grade 310 (UNS S31000) and its low-carbon variant 310S (UNS S31008) are high-alloy austenitic stainless steels engineered for high-temperature service. When drawn into precision capillary tubing formats (typically with outer diameters ranging from 0.5 mm to 10 mm), these alloys provide critical performance metrics for instrumentation, chromatography, aerospace, and furnace sensing arrays.
The excellent high-temperature properties of Grade 310S stem from its chemical composition. By incorporating 24% to 26% Chromium and 19% to 22% Nickel, the alloy forms a stable protective chromium oxide film that resists oxidation in continuous service up to 1035°C (1895°F) and intermittent service up to 1150°C (2102°F). The high nickel content reduces susceptibility to carburizing and sulfidizing environments compared to lower alloyed steels like 304 or 316.
| Grade | Chromium (Cr) | Nickel (Ni) | Carbon (C) | Manganese (Mn) | Silicon (Si) | Phosphorus (P) | Sulfur (S) |
|---|---|---|---|---|---|---|---|
| 310 / UNS S31000 | 24.0 - 26.0% | 19.0 - 22.0% | 0.15% max | 2.00% max | 1.50% max | 0.045% max | 0.030% max |
| 310S / UNS S31008 | 24.0 - 26.0% | 19.0 - 22.0% | 0.08% max | 2.00% max | 1.50% max | 0.045% max | 0.030% max |
A capillary tube is defined not just by its size, but by its strict dimensional tolerances and clean inner surface. At Liaocheng Sihe Stainless Steel Material LTD, we ensure our capillary products maintain high concentricity and a smooth inner bore (Ra < 0.4 µm). This prevents turbulent flow, minimizes blockages in chromatography, and guarantees uniform heat transfer in micro-heat exchangers. The bright annealing process, conducted in a pure hydrogen protective atmosphere, ensures our tubes remain scale-free and ready for high-vacuum applications.
The shifting landscape of modern process engineering, green transition systems, and localized production networks.
Industrial furnaces, gas turbine instrumentation, and thermal processing equipment are transitioning to autonomous feedback loops. This shift requires stable sensor protection tubes—primarily 310S capillary tubing—to protect delicate thermocouple wires under continuous operational heat up to 1100°C.
To optimize thermal dynamics, petrochemical reactors are sizing down their pilot plant sampling systems. Using miniature-diameter, corrosion-resistant 310/310S coiled capillary lines allows engineers to draw high-pressure gas samples directly from high-heat reaction zones without thermal shock or material failure.
Offshore exploration continues to move into deeper, harsher waters. The demand for ultra-long continuous coiled tubing (up to 10,000 meters / 32,800 feet) without orbital joint welds is increasing. High-performance alloys like Incoloy 825, Duplex 2205, and Grade 310S prevent crevice corrosion under marine atmospheres.
For international buyers (specifically from the US, Germany, Spain, and Southeast Asia), verifying the supplier's technical compliance is crucial. Liaocheng Sihe meets these standards by executing rigorous testing protocols:
How Liaocheng Sihe integrates advanced automation with strategic raw material sourcing to ensure supply stability.
Operating from Liaocheng, China, the heart of advanced pipe manufacturing, Liaocheng Sihe Stainless Steel Material LTD leverages Factory 4.0 principles to balance price competitiveness with precision engineering. Across our six dedicated production lines, we control every variable of the cold drawing and rolling processes.
Our multi-pass drawing machinery adjusts speeds dynamically based on load sensors. This minimizes micro-cracking and maintains outer diameter (OD) and wall thickness tolerances within ±0.02mm, even for capillaries below 1.5mm OD.
Integrating real-time heat treatment within the production line prevents oxidation scale. This step eliminates the need for acid pickling, preserving a clean internal bore and yielding ductile, high-strength structural profiles.
Every batch of 310/310S capillary tubing undergoes tensile testing, pneumatic leak testing (up to 100 bar), and chemical composition confirmation (PMI). We guarantee that 100% of our products meet the ordered specifications.
Our advanced bright annealing and drawing production lines.
From subsea wells to high-precision aerospace instrumentation, our alloys deliver stable performance in harsh conditions.
We provide a comprehensive range of stainless steel products and technical services to support demanding project designs:
Seamless coiled tubing available in dimensions from 0.125" to 1" OD. Max continuous length reaches up to 10,000 meters for umbilical systems, minimizing leak risk by reducing fittings.
Ultra-fine diameter tubes for precision sensing, laboratory analysis, and gas chromatography. Manufactured to ASTM A269 standards to ensure tight dimensional tolerances.
Value-added processes including precise CNC bending, spiral forming, micro-cutting, end-flanging, and internal surface polishing (mechanical and electrochemical).
Our high-capacity continuous coil winding and testing facilities.
Liaocheng Sihe is certified to international industrial standards, providing fully traceable manufacturing runs.
A: Grade 310S is a high-alloy austenitic stainless steel designed for high-temperature service. It offers superior oxidation resistance under continuous temperatures up to 1035°C (1895°F) due to its high chromium (24-26%) and nickel (19-22%) content. In contrast, 316L begins to oxidize rapidly above 800°C and is prone to mechanical deformation at high temperatures. 310S provides better creep strength and resists carburizing and sulfidizing in industrial furnace environments.
A: Liaocheng Sihe can manufacture continuous seamless coiled tubing in lengths up to 32,800 feet (10,000 meters) per coil, depending on the outer diameter and wall thickness. These ultra-long coils are ideal for subsea control lines and chemical injection lines, as they minimize the need for intermediate orbital welds, reducing the risk of leak points in high-pressure installations.
A: All export-grade capillary runs undergo strict testing, including: 100% online Eddy Current Testing (ECT) for defect detection, pneumatic leak testing (up to 100 bar) or hydrostatic testing, dimensional checks (using laser micrometer systems for outer diameter and concentricity), mechanical tests (yield, tensile, elongation, and hardness), and metallurgical verification (chemical PMI).
A: Yes, we provide custom sizing. We draw tubes with outer diameters ranging from 0.125 inches (3.175 mm) to 1.0 inch (25.4 mm) and wall thicknesses up to 0.165 inches (3 mm). The inner diameter can be custom configured to meet specific volume or flow requirements, maintaining tolerances within ±0.02 mm to ±0.05 mm.
A: For initial material samples, the lead time is approximately 7 days. For mass production runs, the standard lead time is 20 to 30 days following deposit receipt and dimensional approval. We work closely with our logistics partners to accommodate urgent project timelines.
A: We support standard export terms (FOB, CFR, CIF) and offer payment structures including T/T (30% deposit in advance, 70% balance against the copy of B/L), Western Union, and PayPal. All packages are securely wrapped to protect the capillary coils from physical damage or salt-spray oxidation during maritime transit.
Review our secondary portfolio of high-temperature sheets, custom welding tubes, and super-duplex alloys.
