Heat Exchanger Stainless Steel Tubing

Shuangsen supplies Heat Exchanger Stainless Steel Tubing from China factory direct. Prime 316L and 304 coils from TISCO and Zhangpu are used as raw material. Argon-nitrogen shielded welding plus online annealing solution produce tubing that withstands 10MPa pressure. Internal Ra≤0.2µm after mechanical fine polishing. 1000h salt spray resistance verified. Used in heat exchangers, boilers, condensers, evaporators, and reboilers across chemical, petrochemical, power, pharmaceutical, and food industries.

Coil selection and welding environment control

Production of Heat Exchanger Stainless Steel Tubing begins with prime 316L and 304 coils from TISCO and Zhangpu. Each coil carries a mill certificate and heat number, enabling full traceability from melt to finished tube. The forming and welding line is configured with argon-nitrogen shielding gas delivery, which prevents atmospheric contamination of the weld pool. This controlled atmosphere welding environment eliminates oxide formation and produces a clean, consistent weld bead.

After welding, the tube passes through an online annealing solution treatment. This step restores the metallurgical structure and corrosion resistance of the weld zone, ensuring the weld seam performs identically to the base metal under thermal cycling and pressure. The entire process is monitored continuously for wall thickness, ovality, and weld bead consistency.

Material and welding parameters

• Material grades: 316L (primary), 304 (alternative) – prime coils only
• Coil sources: TISCO and Zhangpu – direct mill certificates provided
• Weld shielding gas: argon-nitrogen mix – prevents oxidation during welding
• Post-weld treatment: online annealing solution – no separate batch annealing required
• Surface finish: mechanical fine polishing – internal and external Ra ≤ 0.2 µm
• Finish alternatives: pickling, bright 180#~600#
• Standing stock: φ 8~25mm available for immediate dispatch

Dimensional range and hydrostatic pressure rating

Standard OD range from 19.0mm to 165.2mm. Wall thickness options from 0.89mm to 3.05mm. Pressure rating reaches 10MPa (30kg) based on hydrostatic testing. Custom dimensions are produced to drawing specifications.

Tolerances follow JIS G3447 or ASTM A269/A270. Lengths typically -0/+10mm.

Physical testing and formability verification

Weld seam integrity and reprocessing capability are confirmed through physical testing. The tubing passes:

• Tube expansion tests – expanded without rupture or cracking
• 180° bending tests – bent without fracture or visible defect
• Flattening tests – flattened without weld seam separation
• Hydrostatic pressure testing – holds 10MPa (30kg) without leakage

These results confirm that the weld seam matches the base metal in strength and ductility. The argon-nitrogen shielded welding process, combined with online annealing, produces a homogeneous weld structure that behaves identically to the parent material under mechanical stress and thermal cycling. This makes the tubing suitable for fabrication processes involving bending, expanding, or flaring during heat exchanger assembly.

Inspection methods and quality documentation

Each batch of Heat Exchanger Stainless Steel Tubing undergoes the following inspection sequence:

• Transverse and longitudinal pressure leveling – confirms ductility and weld soundness
• Reverse flattening – detects weld seam separation or lamination
• Hydrostatic test or eddy current flaw detection – screens for pinholes and linear defects
• Mechanical property verification – tensile strength, yield point, and elongation
• Inner surface roughness measurement – Ra and Rz values per ASTM B912

Traceability is maintained from coil heat number through forming, welding, and finishing. Factory test reports are issued per batch. Third-party inspection (SGS, BV) can be engaged at the production site.

Order specification checklist

1. Product designation
2. Material grade (304 or 316L)
3. Dimensions and tolerance class
4. Quantity (pieces or total length)
5. Packing method (bundles, crates, or custom)
6. Heat treatment condition
7. Testing method (hydrostatic, eddy current, etc.)
8. External surface finish (pickling, 180#~600# bright)
9. Internal wall roughness requirement (Ra, Rz)
10. Special marking or end protection

Heat transfer equipment applications

This tubing is specified for heat exchange equipment across multiple industrial sectors:

• Chemical processing – heat exchangers, reboilers, condensers
• Petroleum refining – cooler and condenser tubes
• Power generation – boiler tubes, economizers, heat recovery
• Pharmaceutical manufacturing – sterile heat transfer equipment
• Food and beverage – pasteurization and sterilization heat exchangers
• HVAC – radiators, heating coils, chilled water systems

Compliance standards and certifications

Certifications held: ISO 9001:2015, ISO 14001:2015, ISO 45001:2018, ISO 13485:2016. National designations: "Specialized, Refined, Unique and New" Little Giant Enterprise and National High-Tech Enterprise.

Frequently asked operational questions

Can the Heat Exchanger Stainless Steel Tubing be produced to non-standard dimensions?
Yes. Custom production covers special OD, wall thickness, length, tighter tolerances, special surface finishes (pickling, 180#~600# bright), OEM marking, and specific end preparations.

Is this a manufacturer or a trading operation?
Direct manufacturer. The facility operates 133 welded pipe lines and performs all key processes in-house.

Are samples available and what is the cost?
Samples are provided free of charge. The receiver covers freight. Lead time: 5–10 working days.

Can the factory be visited or inspected remotely?
On-site visits and online video walkthroughs are available. Real-time quality data can be shared.

What quality assurance procedures are in place?
Three inspection stages: incoming coil verification, in-process checks, and final inspection including NDT, mechanical tests, surface roughness, and dimensional audit.

What is the typical delivery lead time?
Stock items (φ 8~25mm): 3–10 days. Made-to-order: 25–45 days. Large orders: 50–60 days.

How is shipping arranged?
Long-term freight forwarders provide competitive rates. Delivery terms: FOB Ningbo/Shanghai, CIF, or EXW.

What surface finishes can be supplied?
External: pickling, bright 180#, 320#, 400#, 600#. Internal: mechanical polished (Ra ≤ 0.2 µm) or pickled.

Is full traceability maintained?
Each coil is assigned a unique heat number. Full traceability to raw material certificate is maintained.

Why this tubing is selected for heat exchanger applications

• Prime 316L/304 coils from TISCO and Zhangpu – mill certificates provided
• 133 welded pipe lines with proprietary leveling and heat treatment
• Argon-nitrogen shielded welding + online annealing – no separate batch annealing
• In-house NDT and mechanical lab – accelerates batch release
• Proven pressure rating up to 10MPa – hydrostatic tested
• Standing stock φ 8~25mm – reduces lead time
• Non-standard sizes – no minimum batch restrictions
• Full documentation – supports audits and compliance

Shuangsen Pipe Industry – National High-Tech Enterprise. Building a world-renowned Chinese pipeline brand. Every tube, from 19mm to 165mm OD, reflects 25 years of continuous process refinement and strict quality discipline.