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Industries OverviewThe company's products are primarily used in industrial equipment sectors such as nuclear power, petroleum, petrochemicals, chemical engineering, power generation, automotive manufacturing, shipbuilding, fertilizer production, pharmaceuticals, papermaking, sugar refining, and machinery manufacturing. -
Products & SolutionsOur Products: Ferrous metal ore raw materials (nickel ore, ferronickel, ferrochrome, ferromanganese, ferrosilicon, etc.), seamless pipes, welded pipes, medium-thick plates, plate coils, bars, wire rods, wire coils, pipe fittings, flanges, castings, etc. -
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About UsTsisco Industrial Ltd. was established in 2010. Originating from the Tsingshan ecosystem’s Shanghai platform, the company now operates independently and focuses on global supply-chain integration, distribution, and import/export of steel and alloy materials. We achieved ISO 9001 certification from TÜV Rheinland in 2012, and ISO 9001, ISO 14001 and ISO 45001 certifications from LRQA in 2022. These accreditations underpin continuous improvement and stable performance in quality, environment, and occupational health & safety.
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Products & Solutions
Industrial Heater Tubing
Industrial Heater Tubing
Industrial Heater Tubes｜Global Sourcing for Engineering & Procurement
1. Product Positioning and Applications
1. Definition and positioning: Industrial heater tubes transfer heat from fuel combustion, steam or heat-transfer oil, and electric sources to process media. Typical equipment includes fired heaters (radiant and convection sections) for refining and chemicals, electric heater sheaths and nozzle connections, boiler heating surfaces (superheaters, reheaters, economizers, air preheaters), and shell-and-tube process heaters. Media include hydrocarbons and mixed gases, hydrogen-containing atmospheres, steam and water, heat-transfer oils, and sulfur- or chlorine-bearing gases. Materials must satisfy high-temperature creep, oxidation and carburization resistance, sulfidation resistance, wet-corrosion resistance, and weldability/manufacturability.
2. Standards Matrix (Procurement View)
1. Furnace and calculation codes: API 560 for fired heaters, API 530 for tube wall thickness and metal temperature, and API 941 for hydrogen service material limits.
2. Boilers and power: ASME Section I/II; common material standards include ASME/ASTM A213 (seamless boiler and heat-exchanger tubes in alloy/stainless steels) and ASME/ASTM A335 (P-grade high-temperature alloy steel pipe).
3. Stainless and duplex: ASME/ASTM A312 (process austenitic stainless steel pipe), ASME/ASTM A213 (boiler/heat-exchanger tubes), ASME/ASTM A269 (general-purpose), and duplex via ASME/ASTM A789. General requirements use ASME/ASTM A1016.
4. Nickel and high-nickel alloys: ASME/ASTM B407 (Alloy 800H/800HT), B163/B167 (Alloy 600/601), B444 (Alloy 625), with ASME/ASTM B829 as general requirements when applicable.
5. Centrifugally cast furnace tubes: ASME/ASTM A608 (e.g., HK40, HP-Mod).
6. Small-diameter carbon-steel exchanger tubes: ASME/ASTM A179 (condenser and heat-exchanger tubes), ASME/ASTM A192 (boiler tubes); general requirements for carbon/low-alloy via ASME/ASTM A450.
7. U-bend and geometry: TEMA for U-bend and geometry tolerances; electric heater assemblies per IEC/EN 60079 (explosion-protection) and UL 499 where applicable.
3. Scenario–Material–Standard–Size Mapping (Quick Selection)
1. Fired-heater radiant section: For 400–650 °C with moderate sulfidation/coking, select ASME/ASTM A213 T11/T22 or ASME/ASTM A335 P11/P22 and calculate per API 530; when metal temperature exceeds ~600–650 °C or carburization/oxidation intensifies, upgrade to 321H/347H or 800H/800HT; for extreme radiant flux and carburization, adopt ASME/ASTM A608 HP-Mod/HK40. Typical sizes: OD 4–6 in (up to 8 in), wall 8–18 mm, effective length 10–14 m.
2. Delayed coking/asphalt cracking: Prefer T22/P22 or T9/P9; if metal temperature is high and thermal cycling severe, upgrade to 321H/347H/800H; use HP-Mod in extreme cases.
3. Hydro-treating/hydro-cracking (hydrogen partial pressure, HTHA risk): Within API 941 safe zones choose P22/P9 or T22/T9; beyond the safe boundary or to avoid HTHA, use 321H/347H/800H; for very high radiant duty keep HP-Mod as the upper bound.
4. CCR/reforming high-temperature zones (oxidation and carburization): 800H/800HT preferred; for higher heat flux and carbon activity, switch to HP-Mod.
5. SMR/steam-reforming and ethylene cracking coils: Use high-Cr-Ni micro-alloyed centrifugal cast tubes of the HP-Mod family.
6. Convection section and cold end: Use A179/A210 or A213 T11/T22; in acid-dew-point or chloride-condensation zones use 304/316L or 2205/6Mo, and check thermal expansion compatibility. Typical convection sizes: OD 2–3 in, wall 3–6 mm, length 6–9 m; finned tubes optional.
7. Boiler heating surfaces: T22 for mid-temperature sections; T91/T92 for higher steam temperature/stress; economizer/air-preheater with A179/A210 or T11, locally 316L/2205 in corrosion-sensitive areas. Typical OD ~38–60 mm, wall 5–12 mm.
8. Shell-and-tube process heaters (steam or thermal oil): Steam side commonly A179 or T11; process side with chlorides/organic acids use 316L; raise to 2205/2507/6Mo at higher chloride risk or mixed acids; top out with C-276 or 625 for severe corrosion. Sizes per ISO 1127 or drawing.
9. Electric-heater sheaths: Deionized water, fresh water, and glycol use 316L; for higher temperature use 321/347 or 800H; for seawater/brines prefer 625, alternatives 6Mo or 2507 with temperature/crevice limits; hydrocarbons and thermal oils use 316L/321/347, and 800H or 601 at higher oxidation temperatures. Typical sheath sizes: OD 12–22 mm, wall 1.0–2.0 mm, length 2–4 m.
10. Duplex stainless operating boundary: Avoid long-term service above 300–325 °C to prevent sigma-phase formation and 475 °C embrittlement.
4. Size Range and Tolerances (Typical Windows)
1. Hot-rolled/extruded mother-tube capability: OD about 19–260 mm (some mills up to ~320 mm), wall about 3–60 mm, common lengths 6–12 m.
2. Electric-heater sheaths: OD 12–22 mm, wall 1.0–2.0 mm, length 2–4 m.
3. Tolerances and geometry: Minimum wall typically not less than 87.5% of nominal per ASME/ASTM A450 or A1016; ovality, straightness, and squareness per order or TEMA; metric series may reference ISO 1127 classes.
5. Manufacturing Process and Key Controls
1. Seamless rolling route: Piercing, rolling/pilgering, heat treatment (normalize/temper or solution/stabilize), straightening, hydrotest and NDE.
2. Centrifugal casting route: Casting, optional HIP, heat treatment and finish machining, NDE and metallography (e.g., carbide morphology and dendrite spacing per project details).
3. U-bend and serpentine coils: Control bend radius, leg-length tolerance and out-of-plane deviation per TEMA; local post-bend heat treatment and re-hydrotest as needed.
4. Welding and surface: WPS/PQR per ASME IX; for austenitic/nickel alloys control back-purge, heat input, and interpass temperature; for duplex/high-alloy control phase balance via ASTM A923 or ferrite content; bevels and ends per ASME B16.25; pickling/passivation or BA/EP as specified.
6. Quality Inspection and Documentation
1. General and docs: A1016 for stainless/alloy tubes, A450 for carbon/low-alloy, and B829 for nickel/high-nickel when applicable; EN 10204 3.1/3.2 for MTC.
2. Chemistry and mechanics: OES/ICP for chemistry; tensile and hardness, with creep/rupture as required; metallography or grain size and δ-ferrite checks for T91/T92, 800H and cast tubes.
3. Corrosion and phase balance: ASTM A262 for austenitic, ASTM A923 for duplex; ASTM G48 for pitting/crevice with CPT/CCT or mass-loss criteria.
4. NDE and pressure: UT/ET/RT/PT/MT per product standards and A450/A1016; radiant tubes may be hydrotested piece by piece or electrically tested; size and surface per order and applicable standards.
5. Traceability and witnessing: Provide heat-treatment curves, NDE/hydro curves, corrosion/metallography reports; third-party witnessing by TÜV/DNV/LR/SGS as specified; ATEX/IECEx/UL for electric-heater parts when required.
7. Supply Forms and Packaging
1. Forms: Hot-finished or cold-finished straight tubes; U-bends or coils where applicable; ends plain/beveled/expanded per drawings.
2. Packaging and marking: End caps and dry protection, internal cleanliness; pickling/passivation or BA/EP for stainless/nickel alloys; marking with standard, grade, size, heat number, and NDE status; MTC and conformity certificates attached.
8. Order Checklist (Copy-Ready)
1. Code boundary: API 560 and API 530 applicability; hydrogen service requiring API 941; ASME I/VIII and TEMA scope.
2. Grade and standard: Explicitly state grade and standard, e.g., SA213 T22, A608 HP-Mod, B407 800H, B444 625, A179, with corrosion allowance.
3. Size and tolerances: OD × wall × length; choose ASME B36.10 or B36.19 series, or ISO 1127, and quantify eccentricity, ovality, and straightness in the PO.
4. Tests: Chemistry, mechanics, UT/ET/RT, pressure; A262/A923/G48 and metallography/phase balance as required.
5. Heat treatment and ends: Condition; ASME B16.25 bevels/ends; pickling/passivation or BA/EP for stainless/nickel.
6. Docs and witnessing: EN 10204 3.1/3.2; TPI list and report templates; ATEX/IECEx/UL for electric-heater components as applicable.
9. Material Selection—One-Line Guide
Use A335/A213 for steam and pressure; A312 316L for general corrosion resistance; A789 2205/2507 for seawater/brines; B444 (625)/B423 (825)/B167 (600/601)/B622 (C-276/C-22) for severe corrosion or high-temperature carburization; A608 HP-Mod for extreme radiant duty.
10. Risks in Procurement, Installation, and O&M
1. Do not apply API 5L as a furnace-tube standard.
2. Ignoring API 941 hydrogen limits invites HTHA risk.
3. Avoid long-term use of 2205/2507 above 300–325 °C (sigma phase/475 °C embrittlement).
4. Using low-Ni steels in strong carburizing environments without upgrading to 800H/601/625 or HP-Mod.
5. Heater sheath without power-density and flow-rate control causes hotspots and local failures.
6. Acid-dew-point corrosion at the cold end overlooked.
7. U-bends not controlled per TEMA for minimum thinning and geometry.
11. Sample Spec Lines (Drop-in for POs)
1. Radiant section (conventional): SA213 T22, OD 168.3 mm × WT 12.7 mm × L 12 m; API 530 calc; hydrotest each; 100% UT; ASME B16.25 bevel; MTC 3.1 with HT curve and NDE report.
2. Cracking furnace (ultra-high temperature): ASTM A608 HP-Mod, centrifugal cast; finish-machined to OD 139.7 mm × WT 16 mm × L 11.5 m; chemistry/microstructure/creep per project; UT/RT per ITP; hydrotest each; MTC 3.2.
3. Steam heater tubes (shell-and-tube): ASTM A179, OD 19.05 mm × WT 1.65 mm × L 6 m; end expansion/rolling; U-bend per TEMA; 100% hydrotest; MTC 3.1.
4. Heater sheath: UNS N06625 (ASTM B444), OD 19 mm × WT 1.24 mm × L 3 m; power-density and flow per datasheet; 100% ET on welds; MTC 3.1; IEC/EN 60079 alignment.
12. Representative Global Producers (Examples, A–Z)
1. Stainless and nickel alloy seamless/welded tubes: Alleima (ex-Sandvik), Mannesmann Stainless Tubes, Plymouth Tube, Tenaris Dalmine, Tubacex Group, TPS Technitube, Fine Tubes, Centravis, Jiuli, JFE, Nippon Steel Stainless Pipe, Vallourec.
2. Boiler and alloy tubes (carbon and Cr-Mo): Vallourec, Tenaris, JFE, Nippon Steel, TPCO.
3. Centrifugally cast furnace tubes: Duraloy, Manoir, MetalTek (Wisconsin Centrifugal), Paralloy, Schmidt + Clemens.
4. Electric-heater OEM ecosystem (for materials context): Chromalox, Watlow, Thermon, Tempco.
Industrial Heater Tubes｜Technical Specifications
1. Product definition and use
• Tubes for heat input to process media using fuel firing, steam/thermal-fluid, or electric power: fired-heater radiant/convection coils, electric-heater sheaths and nozzles, boiler heat-transfer surfaces, shell-and-tube process heaters.
• Media include hydrocarbons/mixed gases, hydrogenbearing atmospheres, steam/water, thermal oils, sulfur/chloride/acid contaminants.
• Requirements: creep strength at high temperature, resistance to oxidation/carburization/sulfidation, wet-corrosion resistance (pitting/crevice/SCC), weldability and manufacturability.
2. Standards matrix (by application and material family)
• Fired heaters: API 560; API 530; API 941 (Nelson curves).
• Boilers/power: ASME Section I/II; SA-213 for alloy/stainless heattransfer tubes.
• Process/wrought tubes: ASTM/ASME A213 (seamless alloy/stainless), A335 (P-series CrMo), A312 (austenitic SS process pipe), B407 (Alloy 800H/800HT), B163/B167/B444 (Inconel 600/601/625).
• Centrifugal-cast tubes: ASTM A608 (HK40/HP-Mod and related cast alloys).
• Small OD carbon steel: ASTM A179 (HX/condensers), A192 (boilers).
• General requirements: ASTM A450 (carbon/low-alloy), ASTM A1016 (ferritic/austenitic).
• EU/GB/JIS references: EN 10216-2/-5, EN 10217-7, GB/T 5310/13296/14976, JIS G3459/G3463.
• Heat-exchanger geometry and U-bends: TEMA (e.g., RCB-2.31).
• Electric heaters: IEC/EN 60079, UL 499, ATEX/IECEx as applicable.
3. Materials and grades (temperature windows and mechanisms)
• Carbon/low-alloy (to ~450–550 °C and mid-temperature): A179/A210/A106/B; A213 T11/T22; A335 P11/P22.
• Higher Cr-Mo for higher temperature/creep: A213 T9/T91/T92; A335 P9/P91/P92.
• Austenitic SS (600–800 °C, oxidation/sensitization control): A312/A213 TP304H/321H/347H; 316/316L for moderate temperature/corrosion.
• Nickel/highNi (≥800–950 °C or severe carburization/oxidation/sulfidation): B407 800H/800HT; B163/B167/B444 600/601/625; C276 via B622 (seamless)/B619 (welded).
• Centrifugalcast radiant coils: ASTM A608 HK40/HPMod microalloyed families.
• Duplex 2205/2507: strong chloride wet-corrosion zones; avoid sustained >300–325 °C (sigma/475 °C embrittlement).
• Clad/lined: carbonsteel base with CRA liner for combined high-T and wet corrosion.
• Electric sheaths: 316L, 321/347, 800H/800HT, 601/625 (co-design watt density and flow).
4. Sizes and tolerances (typical ranges and general rules)
• Radiant coils: OD 4–6 in (up to 8 in), WT 8–18 mm (per API 530), effective length 10–14 m each.
• Convection banks: OD 2–3 in, WT 3–6 mm, length 6–9 m; finned tubes optional.
• Boiler tubes: OD ~38–60 mm, WT 5–12 mm, cumulative length in km scale.
• Shell-and-tube process heaters: OD 19 mm (3/4”) or 25.4 mm (1”), WT ~1.65–2.11 mm (BWG 14–12), length 3–9 m.
• Electric sheaths: OD 12–22 mm, WT 1.0–2.0 mm, length 2–4 m.
• General tolerances per A450/A1016 or ISO/EN 1127; minimum wall typically ≥87.5% of nominal (−12.5%); ovality, straightness, endsquareness and U-bend Smin per TEMA/PO.
5. Manufacturing and process control
• Wrought tubes (A213/A335/A312/Bseries): piercing → rolling/push bench → heat treatment (normalize/temper, solution/stabilize) → straightening → hydro/NDE.
• Centrifugal cast (A608): spin casting → HIP (if specified) → heat treatment → machining → NDE → metallography/creeprelated microstructure checks per project.
• U-bends and serpentine: control R, leg-difference and out-of-plane per TEMA; local heattreat and re-test when required.
• Electric sheaths: control weld integrity, bend quality, inner-surface defects; design watt density with flow/ΔT to avoid hot spots.
• Welding: WPS/PQR to ASME IX; backpurge and heat-input/interpass control for austenitic/Ni-alloys; duplex per ASTM A923/ferrite balance or project-specified phase targets.
6. Service–material–standard quick mapping (detailed guide)
• Radiant coils (crude/vacuum, 400–650 °C, moderate sulfidation/coking): T11/T22 (A213) or P11/P22 (A335) per API 530; upgrade to 321H/347H or 800H/800HT when TMT >~600–650 °C or carburization/oxidation intensifies; extreme radiant duty → A608 HPMod/HK40 cast.
• Delayed coker/visbreaker: T22/P22 or T9/P9; if sustained high TMT and severe cycling, move to 321H/347H/800H; extreme → HP-Mod cast.
• Hydrotreating/hydrocracking (hydrogen partial pressure, HTHA): select P22/P9 within API 941 safe limits; outside envelope, switch to austenitic 321H/347H/800H; high radiant duty still favors HPMod cast.
• CCR/reformer high-T oxidation/carburization: 800H/800HT; for higher flux/carbon activity adopt HPMod.
• SMR and ethylene pyrolysis radiant: industrystandard centrifugal-cast high Cr-Ni (HP-Mod family).
• Convection sections: A179/A210/A213 T11/T22; for acid-dew-point/chloride coldend corrosion, use 304/316L or 2205/6Mo, verifying CTE/corrosion compatibility.
• Boilers: T22 for midT; T91/T92 for higher steam temperatures/creep; economizer/APH in A179/A210 or T11 with localized 316L/2205 upgrade.
• Shell-and-tube process heating (steam/thermal-fluid): A179 or T11 on steam side; 316L for chloride/organic acid process side; upgrade to 2205/2507/6Mo for high pitting/crevice risk; C276/625 for severe acids.
• Electric heater sheaths: 316L for DI water/fresh water/glycol (control watt density/flow); 321/347 or 800H at higher temperature; seawater/brines prefer 625 (6Mo/2507 as conditional alternatives); hydrocarbons/thermal oils 316L/321/347, upgrade to 800H/601 for higher oxidation skin temperature.
• Generic triggers: TMT >~600–650 °C → from T22/P22 to 321H/347H/800H; >~800–850 °C → HP-Mod cast. Outside API 941 → upgrade to higher CrMo or austenitic/cast. Strong carburization/sulfidation/oxidation → raise Ni/Cr (800H/601/625/HPMod). Wet corrosion (Cl-/acid dew-point/amine/sour water) → 316L/2205/6Mo/Nibase with crevice/stagnation controls. Duplex not for long-term >300–325 °C.
7. QA/QC and testing
• Chemistry/cleanliness: OES/ICP; control C/S/P/N and inclusions; verify Ni/Cr/Mo/Al/Ti windows for Ni-alloys.
• Mechanical/high-T: tensile/hardness; creep/rupture as required; metallography/grain size/δ-ferrite for T91/T92, 800H and cast tubes.
• Corrosion: ASTM A262 (IGC) for austenitic; ASTM A923 for duplex; ASTM G48 for pitting/crevice (define CPT/CCT or mass-loss).
• NDE/hydro: UT/ET/RT/PT/MT per standards/PO; A450/A1016 general rules; radiant coils hydro or electrical alternatives as permitted.
• Geometry/surface: OD/WT/ovality/straightness/end-squareness and bevel; U-bend per TEMA; sheath surface condition and defects recorded.
• Documentation: EN 10204 3.1/3.2; heat-treatment charts, NDE/hydro traces, corrosion/metallography reports; thirdparty witness (TÜV/DNV/LR/SGS) if required.
8. Delivery and packaging
• Ends PE/BE/bevel to ASME B16.25; endcaps, dryness, internal cleanliness; SS/Ni alloy pickled/passivated or BA/EP if specified.
• Long pieces secured for lifting; serpentine/coil sections protected against twist and local denting; clear identification with spec/grade/size/heatlot/NDE status.
• Shipping docs: MTC, NDE/hydro, heat-treat, compliance (API/ASME/TEMA/IECEx/ATEX/UL per project).
9. RFQ/PO checklist
10. Code envelopes: API 560/530; hydrogen service per API 941; boilers/HX per ASME I/VIII + TEMA.
11. Grade and standard: e.g., SA-213 T22 / ASTM A608 HP-Mod / ASTM B407 800H / ASTM B444 625 / ASTM A179, with corrosion allowance.
12. Dimensions: OD × WT × length; bend radius/U-bend; serpentine/loops and circuits; nozzles/headers; allowable ΔP/heat flux; sheath watt density and flow.
13. Inspection: NDE type/ratio (UT/ET/RT/PMI), hydro/electrical test, corrosion/metallography add-ons.
14. Condition/surface: HT condition, pickling/passivation/BA/EP, cleanliness.
15. Docs/witness: 3.1/3.2, third-party, ATEX/IECEx/UL (electric).
16. Packing/ID: endcaps, dryness, crates/skids, barcode/traceability.
17. Installation and construction QA
• Welding to ASME IX; heat-input/interpass control; PWHT as required; post-weld pickling/passivation for SS/Ni.
• Thermal expansion: guides/slides/expansion loops; anti-sag and spacing; support serpentine legs.
• Electric: watt-density/flow adherence; no dry-fire; hazardous-area terminations.
• Decoking: compatible procedures and cycles; avoid thermal shock.
• Corrosion mitigation: dew-point and chloride-laden zones protected; avoid crevices and condensate traps.
11. Common pitfalls and risk controls
• Using API 5L as heatertube basis (wrong).
• Ignoring API 941, risking HTHA.
• Longterm >300–325 °C service with duplex steels.
• LowNi steels in strong carburization; should use 800H/601/625/HPMod.
• Electric sheaths with excessive W/cm² and low flow → hotspot failure.
• Convection cold-end acid-dew-point corrosion not addressed.
• U-bend geometry (Smin/out-of-plane) not controlled per TEMA.
12. Global industry clusters and representative companies (alphabetical, indicative)
• Centrifugal-cast radiant tubes: Duraloy (US), Manoir (FR), MetalTek (US, Wisconsin Centrifugal), Paralloy (UK), Schmidt + Clemens S+C (DE).
• Stainless/Ni alloy seamless/welded: Alleima (SE), Mannesmann Stainless Tubes (DE), Plymouth Tube (US), Tenaris Dalmine (IT), Tubacex Group (ES), TPS Technitube (DE), Fine Tubes (AMETEK, UK), Centravis (UA), Jiuli (CN), JFE (JP), Nippon Steel Stainless Pipe NSSP (JP), Vallourec (FR).
• Boiler/carbon-alloy tubes: Vallourec, Tenaris, JFE, Nippon Steel, TPCO (CN).
• Electric-heater ecosystem (for sheath/application context): Chromalox, Watlow, Thermon, Tempco.
13. Example spec lines
• Radiant, conventional: “SA-213 T22, OD 168.3 mm × WT 12.7 mm × L 12 m, API 530 calc; 100% UT; hydro each; ASME B16.25 bevel; MTC 3.1 + HT chart + NDE report.”
• Pyrolysis radiant, extreme: “ASTM A608 HP-Mod centrifugal-cast, machined to OD 139.7 mm × WT 16 mm × L 11.5 m; chemistry/metallography/creep per project; UT/RT per ITP; hydro each; MTC 3.2.”
• Convection: “SA-213 T11, OD 60.3 mm × WT 4.5 mm × L 9 m; finned in zones as noted; UT/ET sampling; hydro per A450.
• Shell-and-tube steam heater: “ASTM A179, OD 19.05 mm × WT 1.65 mm × L 6 m; expanded/rolled ends; U-bends per TEMA; 100% hydro; MTC 3.1.”
• Electric sheath: “UNS N06625 (ASTM B444), OD 19 mm × WT 1.24 mm × L 3 m; watt-density/flow per datasheet; 100% ET on welds; MTC 3.1; IEC/EN 60079 compliance.”
14. Early estimates and checks
• Radiant area A ≈ Q / q″ (Q in MW, q″ ≈ 20–60 kW/m²); tube count n ≈ A / (π·OD·L_eff). Finalize with API 530 thickness, supports/spacing, ΔP/heatflux optimization, and API 941 check for hydrogen service.
• Electric sheaths: element count ≈ total kW ÷ unit kW; verify W/cm² and min. flow to prevent film boiling and hot spots.
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