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Utilizing 26 high-precision cold rolling mills and 6 cold drawing machines, we ensure dimensional accuracy and superior mechanical properties.
Extra Long Stainless Steel Tubing
ASTM A213 / A249 | Up to 25,000mm Length | TP304L / TP316L / S32205 | Heat Exchanger Grade
ISO 9001 | TEMA | Laser Straightness VerifiedRelated Products
Introduction
In the engineering of large-scale industrial heat exchangers, once-through steam generators, geothermal energy recovery systems, and long-span process cooling installations, a single dimensional parameter — tube length — can have a transformative impact on the technical performance and economic viability of the entire system design. Extra Long Stainless Steel Tubing, defined here as seamless and welded stainless tubes supplied in lengths exceeding the standard random mill length of 6–8 meters and reaching continuous lengths of 20,000mm, 25,000mm, and beyond, enables heat exchanger designers to pursue configurations that deliver superior thermal efficiency, reduced flow resistance, fewer joint connections, and lower total installed cost compared to equivalent heat exchanger designs constrained to standard tube lengths. The relationship between tube length and heat exchanger performance is fundamentally governed by the heat transfer equation: for a given tube OD, wall thickness, and grade, increasing tube length allows a larger heat transfer area to be accommodated within a single-pass shell without the pressure drop penalty associated with multi-pass tube arrangements, and without the increased leak risk that accompanies the additional tubesheet joints required in multi-shell heat exchanger trains with standard-length tubes. In large-scale power plant condensers, desalination plant multi-stage evaporators, and industrial process heat recovery exchangers where individual tube lengths of 15,000–25,000mm are specified by thermal design engineers to optimize shell diameter, tube count, and overall heat exchanger volume, extra long stainless tubing represents the enabling material specification that makes the thermal design achievable with the minimum number of individual components and weld joints.
The production of extra long stainless steel tubing requires manufacturing process capabilities that exceed those of standard mill tube production in several critical dimensions. For seamless extra long tubes, the piercing and elongation sequence of the hot extrusion process must produce a seamless hollow of sufficient length that the subsequent cold-drawing reduction sequence — typically comprising 3–5 drawing passes with intermediate annealing — can achieve the final finished length of 20,000mm or greater while maintaining the geometric straightness, dimensional consistency, and surface quality required for heat exchanger tube bundle assembly. The progressive reduction of tube length in each cold-drawing pass creates an inherent relationship between starting length and finishing length that constrains the maximum achievable finished tube length for a given OD and wall thickness — a constraint that our production planning team manages through careful scheduling of extended-length billet production, optimization of per-pass reduction ratios, and specialized handling of extra-long tube blanks during the annealing and straightening operations that are critical quality-determining steps in the extra long tube production sequence. For welded extra long tubes in diameters above approximately 38mm, the continuous roll-forming and high-frequency welding process can produce strip-welded tube in essentially unlimited lengths limited only by the coil weight of the feed strip — a production advantage that makes welded tube the preferred manufacturing route for large-diameter extra long heat exchanger tube specifications where seamless production would require specialized very large extrusion equipment.
The dimensional quality requirements for extra long stainless heat exchanger tubing are more demanding than for standard-length tubes in two critical parameters: straightness and dimensional consistency along the full tube length. A tube that is straight to within 1mm per meter over a 6-meter length has a total bow of 6mm — acceptable for most heat exchanger bundle assembly operations. The same proportional straightness specification applied to a 24-meter tube produces a total bow of 24mm — potentially sufficient to cause tube-to-baffle clearance issues and tube-to-tube contact in a closely pitched tube bundle layout with narrow baffle spacing. Extra long tube straightening therefore requires specialized multi-roll straightening equipment capable of processing the full tube length in a single pass with independently adjustable roll pressures that correct not just global bow but also local curvature variations along the tube length. Our straightening capability, verified by laser straightness measurement of 100% of extra long tubes before dispatch, ensures that delivered tubes meet the ≤1.5mm/m local straightness and ≤20mm total bow specifications that TEMA standard heat exchanger designs require for reliable tube bundle assembly without rework or remedial straightening on site.
Our extra long stainless steel tubing program covers seamless and welded product forms in TP304L, TP316L, TP321, duplex S32205, and super duplex S32750, available in standard heat exchanger OD dimensions from 15.88mm to 50.8mm with fixed lengths from 9,000mm to 25,000mm in 500mm increments. Dimensional verification of every tube including OD, wall thickness, and straightness is performed and documented before dispatch. All tubes are supplied with EN 10204 3.1 Mill Test Reports with actual chemistry, mechanical properties, and NDE results. For power plant and refinery heat exchanger projects requiring extra long tubes in large quantities with fixed-length dimensional tolerance of ±3mm, we provide project-specific production scheduling to ensure dimensional consistency across all tubes in the bundle, eliminating the dimensional variation between production lots that creates tube-to-tubesheet joint inconsistency in large heat exchanger bundle fabrication programs.
Specifications
| Available Grades | TP304L, TP316L, TP321, S32205, S32750 |
| Standard | ASTM A213, A249, EN 10216-5 |
| Outer Diameter | 15.88mm - 50.8mm |
| Wall Thickness | 1.0mm - 4.0mm |
| Maximum Length | 25,000mm (Fixed ±3mm) |
| Straightness | ≤1.5mm/m Local, ≤20mm Total (Laser Verified) |
Chemical Composition (TP316L)
| Element | C | Cr | Ni | Mo | Mn | Si | N |
| Value (%) | ≤0.030 | 16.0-18.0 | 10.0-14.0 | 2.0-3.0 | ≤2.00 | ≤0.75 | ≤0.10 |
Up to 25,000mmLaser StraightnessTEMA HX Ready
Mechanical Strength (TP316L)
Comprehensive Info
| MOQ | 200kg per dimension (Project quantities) |
| Lead Time | 30 - 55 Days |
| Packaging | Extra-Long Plywood Crates / Steel Racks |
| Certifications | ISO 9001, TEMA, PED, ASTM A213 |
| Raw Materials | Premium Low-Carbon Austenitic / Duplex Melt |
| Customization | Grade, OD/WT, Fixed Length ±3mm, Straightness Report |
Applications
Power Plant CondensersExtra long TP316L tubes for large surface condenser tube bundles in fossil fuel, nuclear, and geothermal power generation facilities
Desalination Evaporators20,000mm+ tubes in multi-stage flash and multi-effect distillation evaporator tube bundles for large-scale seawater desalination
Industrial Process Heat RecoveryLong-tube waste heat recovery exchangers in cement, glass, and steel plant exhaust gas cooling and heat recovery systems
Refinery Overhead CondensersExtra long tubes minimizing tube joints in large crude distillation overhead condensers handling corrosive overhead vapor streams
Once-Through Steam GeneratorsExtended tube lengths in once-through steam generator (OTSG) designs for nuclear and industrial process steam production
Offshore Platform Cooling SystemsS32205 extra long tubes for large-capacity offshore seawater cooling heat exchangers requiring minimum tube-to-tubesheet joints
Advantages
25,000mm Single-Piece Length
Eliminates intermediate tube-to-tubesheet joints in long heat exchanger designs — each eliminated joint removes one potential leak path, one hydraulic expansion or seal weld operation, and one dimensional quality inspection point from the bundle fabrication program.
Laser Straightness Verification
100% laser straightness measurement of every tube with ≤1.5mm/m local and ≤20mm total bow certification — ensuring drop-in tube bundle assembly without on-site remedial straightening that delays fabrication schedules.
Thermal Efficiency Optimization
Longer tube length enables single-pass shell designs with maximum LMTD — the thermal driving force — for superior heat transfer efficiency compared to multi-pass arrangements needed to achieve equivalent duty with standard-length tubes.
Project Batch Consistency
Production scheduling of complete project tube quantities from a single production campaign ensures dimensional and mechanical property consistency across the entire tube bundle — eliminating inter-lot variation that creates joint tightness variations in large heat exchanger fabrication programs.
About Jiangsu Jend Tube Co.,Ltd.
As China Extra Long Stainless Steel Tubing Manufacturers and Wholesale Extra Long Stainless Steel Tubing Factory, Established in 2011 and is a manufacturing enterprise with a complete manufacturing cycle from raw material selection to finished product delivery. The company currently has more than 100 employees, covers an area of 30015 square meters, and has a registered capital of 48 million yuan, annual production capacity of 3800 tons.
The company has passed ISO9001:2015 quality certification, domestic pressure vessel TS certification, and foreign pressure vessel PED certification. With rich experience and mature technology, we have been expanding our market internationally. At present, our products are exported to more than 50 countries and regions including Europe, America, Southeast Asia, and the Middle East.
The company adheres to different production norms and standards such as the American standard (ASTM), the European standard (EN), the German standard (DIN), the Japanese standard (JIS), the Russian standard (GOST), and the Chinese standard (GB).
Our company specializes in and customizes various specifications of Martensite TP410 (0Cr13, 1Cr13), Ferrite TP405 (1Cr13Al), TP430 (1Cr17), TP444 (0Cr18Mo2), TP439, TP409 (0Cr11Ti), It is also proficient in manufacturing Austenitic seamless stainless steel pipes of series such as TP304(L/H), TP316(L/H/Ti), TP310S, TP317, TP321(H) and TP347(H). Duplex such as S31803, S2205, S32750, S32304, and Nickel-based alloys Monel400, Monel600, Monel800, GH3030, 904L, Inconel 625, etc.
The company mainly produces seamless steel pipes with the following specifications: outer diameter: 3.18mm to 406.4mm, wall thickness: 0.3mm to 20mm, and the longest length is 25000mm. Additionally, it can customize seamless steel pipes with special materials and specifications according to customer requirements. The company attaches great importance to scientific innovation. The staff of the company vigorously develop technological research and development.
Jiangsu Jend Tube Co.,Ltd. will continuously accumulate professional knowledge and capabilities, striving to become a leader in the domestic market and even the world market. Strive to be the most reassuring pipe manufacturing enterprise for customers.
Precision Manufacturing and Process Optimization
We rely on precision equipment and optimized production technologies to achieve outstanding mechanical performance and consistent product quality.
Cold Rolling and Cold Drawing
Solution Heat Treatment
Natural gas solution treatment furnaces and BA solution treatment furnaces optimize the material's grain structure, enhancing corrosion resistance.
Precision Straightening and Polishing
10 straightening machines and 8 finishing polishing machines guarantee product surface smoothness and dimensional accuracy.
Automated Inspection and Quality Assurance
Real-time monitoring systems ensure the stable quality of every batch of products.
Product Usage Tips
Logistics Planning for Extra Long Tubes
Tubes above 12,000mm require flatbed trailer transport with over-length permits and specialized loading fixtures to prevent tube contact damage during transit. Plan logistics from our factory to the fabrication workshop at the project engineering stage — access road clearance, workshop bay length, and crane lift capacity must all accommodate the extra long tube dimensions before finalizing the tube length specification with the heat exchanger thermal designer.
Straightness Verification on Receipt
Verify tube straightness on receipt before beginning tube bundle assembly — transportation vibration and improper stacking during transit can introduce local bow in extra long tubes that were straight when dispatched. Inspect using a taut wire reference along the full tube length and verify local deviation does not exceed the TEMA design clearance between tube OD and baffle hole ID. Mark and segregate any tubes exceeding the straightness tolerance before bundle assembly commences.
Thermal Expansion Allowance
Extra long tubes have proportionally greater thermal expansion under operating temperature conditions — a 25,000mm TP316L tube operating at 200°C above ambient experiences approximately 45mm of thermal elongation relative to the fixed tubesheet. Verify that the heat exchanger design includes an adequate expansion accommodation mechanism — floating head, U-tube configuration, or bellows expansion joint — to prevent excessive thermal stress in the tube-to-tubesheet joints under the larger absolute thermal expansion of extra long tube designs.
Hydrostatic Test After Bundle Assembly
Conduct hydrostatic pressure testing of the completed extra long tube bundle at the TEMA or ASME-specified test pressure before shell installation to verify all tube-to-tubesheet joint integrity. For very long tube bundles where individual tube straightness variation accumulates across the full length, joints at both the fixed and floating tubesheets should be inspected with equal diligence as differential expansion during the test cycle from ambient to test pressure can selectively stress joints at one end more than the other.
Value-Added Processing Services
We provide project-specific processing for extra long heat exchanger tube supply programs:
Fixed-Length Precision Cutting
±3mm fixed-length cutting with individual tube length measurement record for TEMA heat exchanger bundle assembly.
Laser Straightness Report
100% laser straightness measurement with individual tube straightness certificate for every length supplied.
ET + Hydrostatic Testing
Combined eddy current and hydrostatic testing per ASTM A213 for complete tube integrity qualification.
Project Batch Scheduling
Complete project quantity production from a single campaign ensuring inter-tube dimensional consistency across the full bundle.
Payment & Shipping
Payment Terms
- T/T (Telegraphic Transfer)
- L/C at Sight (Letter of Credit)
- Western Union
- Flexible terms for long-term partners
Shipping Options
- Sea Freight (FCL — open-top or flat-rack container for lengths above 12m)
- Over-dimensional road transport with permits for domestic delivery
- Specialized cradle and tie-down loading for transit damage prevention
- Full transit insurance for extra long tube consignments
Certifications & Standards
Our extra long stainless steel tubing is manufactured and certified to heat exchanger and pressure tube standards:
ISO 9001:2015
ASTM A213 / A249
TEMA Standards
EN 10216-5
PED Certification
EN 10204 3.1 MTR
Frequently Asked Questions
What is the maximum tube length you can supply?
We supply extra long stainless heat exchanger tubing up to 25,000mm (25 meters) in standard heat exchanger OD dimensions from 15.88mm to 50.8mm. Lengths beyond 25,000mm are potentially feasible for welded tube grades in larger ODs — contact our engineering team for feasibility assessment of specific dimensions above 25 meters.
Why use extra long tubes instead of standard length tubes in heat exchangers?
Extra long tubes reduce the number of tube-to-tubesheet joints — each joint is a potential leak site and requires individual hydraulic expansion or seal welding during fabrication. In a condenser with 10,000 tubes at 20m length versus two 10m shells, the extra long tube design eliminates 10,000 intermediate tubesheet joints, dramatically reducing both fabrication manhours and long-term leak risk in service.
What straightness tolerance is achievable for 20,000mm tubes?
We achieve ≤1.5mm/m local bow and ≤20mm total bow for 20,000mm tubes, verified by 100% laser measurement. This corresponds to a maximum total bow of 30mm at full length — within the clearance available in standard TEMA baffle hole designs for most tube OD and pitch combinations used in large heat exchanger specifications.
How are extra long tubes packaged and shipped?
Tubes above 12,000mm are shipped in custom-length plywood crates on open-top or flat-rack sea containers. Cradle supports prevent tube sagging and contact damage during ocean transit. Road transport from port to fabrication workshop uses flatbed trailers with over-length permits and escort vehicles where required by local regulations. We coordinate full transport logistics from factory to fabrication site for extra long tube project supplies.
Can seamless extra long tubes be produced in duplex grade S32205?
Yes, seamless S32205 duplex extra long tubing is available up to 20,000mm length in the standard heat exchanger OD range. Duplex grades are increasingly specified for offshore and seawater heat exchanger extra long tube designs where the higher yield strength reduces required wall thickness and the PREN >34 provides reliable pitting resistance in warm seawater service that austenitic TP316L cannot match.
What length tolerance is achievable for fixed-length extra long tubes?
Fixed-length cutting tolerance of ±3mm is standard for tubes up to 20,000mm. For tubes above 20,000mm, ±5mm is the achievable tolerance due to the longer measurement and handling distance involved in precision-cutting very long tubes. Both tolerances are within the TEMA standard allowance for heat exchanger tube length variation in normal bundle assembly operations.
What is the typical lead time for extra long stainless tubing?
Extra long tube production requires extended production scheduling for the multi-pass cold-drawing sequence and final precision straightening. Typical lead time is 30–55 days depending on grade, dimensions, required length, and total project quantity. Project orders should be placed minimum 10 weeks before required delivery to the heat exchanger fabrication workshop to allow adequate production and logistics scheduling.
Is eddy current testing available for extra long heat exchanger tubes?
Yes, 100% eddy current testing per ASTM E426 is available for all extra long stainless heat exchanger tube grades. ET testing is performed on a continuous draw-through testing machine that scans the full tube length in a single pass, with calibrated reference defect sensitivity. Combined ET plus hydrostatic testing is recommended as the standard NDE specification for critical power plant and offshore heat exchanger tube supply programs.
Ready to Order Extra Long Stainless Steel Tubing?
Up to 25,000mm, laser straightness certified, TEMA compliant — the heat exchanger tube specialists for large-scale projects
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