Data Center Liquid Cooling Stainless Steel Tube
Short Description:
Stainless steel tubing and drawing-based tube components for CDU internal piping, TCS supply and return lines, rack manifolds, cold-plate circuits and RDHx loops. Welded, seamless, precision and fabricated forms are available in 304, 304L, 316L and other grades to project specification.
Liquid Cooling Tube Overview
SAKYSTEEL supplies stainless steel tubing and drawing-based tube components for coolant distribution units (CDUs), technology cooling system supply and return lines, row or rack manifolds, cold-plate circuits and rear-door heat-exchanger loops. Welded, seamless, precision and fabricated forms can be produced to the selected standard, drawing and project acceptance requirements.
| Material Grades | 304 / 304L / 316L; other stainless grades to specification |
|---|---|
| Tube Types | Welded, seamless, precision straight tube and fabricated tube components |
| Common Reference Sizes | OD 9.5–114.3 mm; wall 0.80–3.05 mm; length 3500–7500 mm; other sizes and cut lengths by drawing |
| Cross Sections | Round, square, rectangular and drawing-based hollow sections |
| Surface Conditions | Pickled, bright annealed, mechanically polished or electropolished |
| Supply Basis | Standard dimensions, special tolerances, formed ends and fabricated details to purchase specification |
Where the Tube Is Used in a Liquid Cooling System
| CDU Internal Piping | Connects the heat exchanger, pumps, filters, valves and supply or return ports inside the coolant distribution unit. |
|---|---|
| TCS Supply and Return Lines | Transfers controlled coolant between the CDU and row or rack distribution points. |
| Row and Rack Manifolds | Used as distribution headers and drawing-based branch assemblies for multiple rack connections. |
| Cold Plate and RDHx Loops | Supports direct-to-chip cold-plate and rear-door heat-exchanger coolant circuits where the approved system design specifies stainless tubing. |
Selection basis: identify the exact loop, coolant chemistry, temperature, design pressure, test pressure, connection method and complete wetted-material list before the tube specification is finalized.
Material Grade Selection
| Grade | UNS / EN | Procurement Basis |
|---|---|---|
| 304 | S30400 / 1.4301 | General austenitic stainless grade; confirm against coolant chemistry and external environment. |
| 304L | S30403 / 1.4307 | Low-carbon grade commonly selected for welded tubing and fabricated assemblies. |
| 316L | S31603 / 1.4404 | Molybdenum-bearing low-carbon grade considered where project corrosion conditions are more demanding. |
Applicable Tube Standards
| Standard | Applicable Scope |
|---|---|
| ASTM A269/A269M-25 | Seamless and welded austenitic stainless tubing for general service. |
| ASTM A249/A249M-24aε1 | Welded austenitic steel boiler, heat-exchanger and condenser tubes. |
| JIS G 3463:2023 | Stainless steel boiler and heat-exchanger tubes; generally applicable to OD 15.9–139.8 mm. |
| DIN 17457 / DIN EN 10217-7:2021 | Welded stainless steel tubes for pressure purposes; use the current purchase specification on the order. |
| GB/T 24593-2018 | Welded austenitic stainless steel tubes for boilers and heat exchangers; standard scope up to OD 305 mm and wall 8.0 mm, with other dimensions by agreement. |
Dimensional Tolerance Reference
ASTM A269/A269M Typical Dimensional Tolerances
| Outside Diameter | OD Tolerance | Wall Tolerance | Cut Length Over / Under |
|---|---|---|---|
| Up to 12.7 mm | ±0.13 mm | ±15% | +3.2 / 0 mm |
| 12.7 to <38.1 mm | ±0.13 mm | ±10% | +3.2 / 0 mm |
| 38.1 to <88.9 mm | ±0.25 mm | ±10% | +4.8 / 0 mm |
| 88.9 to <139.7 mm | ±0.38 mm | ±10% | +4.8 / 0 mm |
| 139.7 to <203.2 mm | ±0.76 mm | ±10% | +4.8 / 0 mm |
ASTM A249/A249M Typical Dimensional Tolerances
| Outside Diameter | OD Tolerance | Wall Tolerance | Cut Length Over / Under |
|---|---|---|---|
| Under 25.0 mm | +0.10 / −0.11 mm | ±10% | +3.0 / 0 mm |
| 25.0 to 40.0 mm | ±0.15 mm | ±10% | +3.0 / 0 mm |
| >40.0 to <50.0 mm | ±0.20 mm | ±10% | +3.0 / 0 mm |
| 50.0 to <65.0 mm | ±0.25 mm | ±10% | +5.0 / 0 mm |
| 65.0 to <75.0 mm | ±0.30 mm | ±10% | +5.0 / 0 mm |
| 75.0 to 100.0 mm | ±0.38 mm | ±10% | +5.0 / 0 mm |
| >100.0 to 200.0 mm | +0.38 / −0.64 mm | ±10% | +5.0 / 0 mm |
Order note: tolerance values must be checked against the selected standard edition, manufacturing route, tube size and purchase order. Special tolerances can be produced to an approved drawing or technical agreement.
Surface, Cleanliness and Delivery Options
| Internal Surface | Bright annealed, mechanically polished or electropolished; roughness requirement stated on the order. |
|---|---|
| Internal Condition | Oil, particle, moisture and residue limits defined by the project cleanliness specification. |
| Cleaning and Protection | Flushing, drying, protective wrapping and capped ends available to the agreed delivery requirement. |
| Fabrication Controls | OD or section, wall, bend radius, straightness, twist, cut length, weld condition and connection details controlled by drawing. |
Inspection and Quality Control
Inspection requirements are defined by the applicable material standard, tube type, drawing and purchase specification. Test methods, sampling scope, acceptance criteria and required reports are confirmed before production.
| Inspection Group | Inspection Item | Verification |
|---|---|---|
| Mechanical & Formability | Tensile Test | Tensile strength, yield strength and elongation. |
| Hardness Test | Material hardness against the specified requirement. | |
| Flattening Test | Tube ductility, formability and weld integrity where applicable. | |
| Bend Test | Bending performance and resistance to cracking. | |
| Material & Surface | Positive Material Identification (PMI) | Alloy grade and material identity. |
| Surface Roughness Measurement | Specified surface roughness, including Ra when required. | |
| Liquid Penetrant Testing (PT) | Surface-breaking discontinuities in welded or fabricated areas. | |
| Intergranular Corrosion Test | Susceptibility to intergranular corrosion under the specified method. | |
| Tube Integrity | Eddy Current Testing (ECT) | Discontinuities in seamless or welded stainless steel tubing. |
| Hydrostatic Pressure Testing | Tube pressure integrity and leakage resistance. |
Inspection note: testing scope and documentation are supplied according to the applicable standard, purchase specification and agreed inspection plan. Not every test is required for every order.
Mechanical & Formability Testing
Flattening Test
Evaluates tube ductility, formability and weld integrity where applicable.
Tensile Test
Measures tensile strength, yield strength and elongation.
Material & Surface Verification
Positive Material Identification (PMI)
Confirms alloy grade and material identity.
Surface Roughness Measurement
Measures the specified tube surface roughness, including Ra when required.
Tube Integrity Testing
Eddy Current Testing (ECT)
Detects discontinuities in seamless or welded stainless steel tubing.
Hydrostatic Pressure Testing
Verifies tube pressure integrity and leakage resistance.
Information Required for a Liquid Cooling Tube Quote
| Material and Standard | Grade, applicable standard and required edition. |
|---|---|
| Dimensions | Drawing or OD/section, wall thickness, length and tolerances. |
| Operating Conditions | Coolant type and concentration, operating temperature, design pressure and test pressure. |
| Surface and Cleanliness | Surface condition, internal roughness, particle or residue limit, cleaning and end protection. |
| Fabrication and Delivery | Connection details, drawing features, documentation, packing and quantity. |
Send Your Liquid Cooling Tube Drawing
Submit the application, drawing and purchasing requirements for a specification review and quotation.
