ISO 9001 · EN 9100 certified EN 10204 3.1 MTC on every heat
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Nickel-alloy tube that arrives certified, on time, and to spec.

Zero weld-seam construction for extreme service. Backed by an EN 10204 3.1 certificate on every heat, a named engineer on every account, and an on-time delivery guarantee — or we cover the freight.

Get a certified quote → Calculate tube weight ↓
No MOQ on stock grades OD 3–610 mm 14 ASTM standards covered
24hQuote SLA
99.2%On-time delivery
0MTC rejections '24
4.9/5Buyer rating
Nickel alloy seamless pipes — TrueGrade Metals studio product shot
OD 3–610 mm WT 0.1–60 mm
Engineer online now
JL

Meet James Lin — your dedicated engineer

Senior sales engineer · Metallurgist · 24h technical SLA

One senior metallurgist owns your project from RFQ through delivery — technical answers within 24 hours, direct line, no ticket queues.

Email James WhatsApp →
01 — Where projects go wrong

The 6 sourcing headaches — and how we fix them.

Compiled from 217 buyer reviews and 900+ international shipments since 2019.

02 — Three promises, in writing

We put the risk on our side of the table.

Promise 01

Certified or refunded

If any heat fails MTC verification at your incoming inspection, we replace it or refund in full — no dispute process.

Promise 02

On time, or we cover freight

Delivery date fixed at PO acceptance. Miss it by more than 5 working days and we absorb the freight cost.

Promise 03

Named engineer, one contact

One senior metallurgist owns your project from RFQ through delivery. No handoffs, no lost context.

03 — A recent project

Subsea umbilical: 4.2 t of Inconel 625, Rotterdam in 47 days.

Challenge

Original supplier missed the MTC 3.2 requirement and cracked the delivery date. Buyer needed a re-source with only 8 weeks to the first-oil deadline.

What we did

Reserved an existing heat lot within 48 h. Bureau Veritas witnessed the hydrostatic test on-site. Air-freight-rated wooden crates for the polished OD.

Outcome

All 148 pieces delivered day 47. Zero incoming rejections. Buyer converted to a blanket order for 2026 — 32 t across 4 grades.

"TrueGrade stepped in on 48 hours' notice and hit every date. They're now our first-call supplier for nickel alloys."— Marc D., Procurement Lead, offshore EPC
04 — Spec configurator

Build your exact tube spec. Get the weight instantly.

Configure grade, dimensions and finish — the calculator applies grade-specific density (ρ) for per-piece and total shipment weight, exactly what you need for freight, budgets and PO drafting.

Range: 3 – 610 mm
Range: 0.1 – 60 mm
Standard: 6000 / 12000 mm
Unit weight—kg/m
Per piece—kg
Total shipment—kg

—

Formula
m = (OD − WT) × WT × L × ρ × π
L is length and ρ is grade density (g/cm³). Result in kg per piece.
05 — Technical performance

Data your engineers can defend in review.

Cross-grade mechanical, thermal, corrosion and composition data. Every point is the nominal published property — certified heat lots ship with actual MTC values.

Tensile & yield strength at room temperature

MPa, longitudinal, annealed condition unless noted

Highest yield

Inconel 718 — 1035 MPa

Aged temper for turbine sections and high-load fasteners.

Best hot strength

Inconel 625 — 335 MPa @ 600 °C

Mo + Nb solid-solution strengthening, no aging needed.

Highest PREN

Hastelloy C-276 — PREN 68

Chloride pitting immune; worst-case chemical exposure.

Best ductility

Monel 400 — ~45% elongation

Formability retained for severe bending and flanging.

Tensile strength vs. service temperature

Inconel 625 vs. Inconel 718 vs. Incoloy 825 — where each alloy stops working

Pitting resistance equivalent number (PREN)

Higher = better resistance to chloride pitting & crevice corrosion

Nominal chemistry — nickel content drives the family

wt % nickel (balance) by grade — Mo, Cr, Nb and Cu define each alloy's character

06 — Grade explorer

Four families. 60+ grades. Zero compromise on chemistry.

Every grade below is stocked or on a frequent smelting rotation — shorter lead times and heat-lot flexibility.

07 — Manufacturing

19-step process. 100% NDT. Zero surprises at incoming inspection.

Every heat is PMI-verified, hydrostatically tested and shipped with EN 10204 3.1 documentation.

Governing standards

14 international standards fully covered

  • ASTM B161Ni 200/201 seamless pipe & tube
  • ASTM B163Condenser & heat-exchanger tube
  • ASTM B165Monel 400 seamless pipe & tube
  • ASTM B167Inconel 600/601/690 pipe & tube
  • ASTM B407Incoloy 800/800H/800HT tube
  • ASTM B423Incoloy 825 seamless tube
  • ASTM B444Inconel 625 & 625LCF seamless
  • ASTM B535Incoloy 330 seamless pipe
  • ASTM B622Hastelloy B / C-276 / C-22 / G-30 tube
  • ASTM B677Alloy 904L / UNS N08926 tube
  • ASTM B729Alloy 20 seamless tube
  • ASTM B829General requirements, pipe & tube

Quality documentation

Included in every shipment

  • Mill Test Certificate EN 10204 3.1
  • Chemical composition (ladle + product)
  • Mechanical test report (tensile, hardness)
  • Hydrostatic pressure test log
  • NDT report (ET / UT / visual)
  • PMI verification per heat number
  • Dimensional inspection report
  • Packing list & certificate of origin
ISO 9001ISO 14001ISO 45001EN 9100PED 2014/68
08 — Dimensional data

ANSI B36.10 / B36.19 wall-thickness reference.

Select a schedule to highlight its column. Values in millimetres. Custom OD/WT outside standard schedules available on request.

NPSDNOD (mm)SCH 10SCH 40SCH 80SCH 160

Highlighted column = selected schedule. Tolerances per ASTM B829; tighter tolerances by agreement.

Tolerance — cold worked

  • OD 10–16 mm: ±0.13 mm
  • OD 16–38 mm: ±0.19 mm
  • OD 38–76 mm: ±0.25 mm
  • OD 76–152 mm: ±0.51 mm
  • Wall thickness: ±10–15%

Delivery states

  • Cold rolled / drawn: pickled, polished, sand-blasted
  • Annealed: pickled, polished, sand-blasted
  • Lengths: 1 m / 6 m standard; 12 m & 24 m on request
  • Cut lengths: laser / plasma / waterjet options
09 — Buyer voices

Sourcing agents don't leave 5-star reviews unless the delivery earns it.

★★★★★
The quotation was clear and easy to review. Pricing on both Inconel 625 and Hastelloy C-276 helped us compare alternatives for the Pointe-Noire project without extra rounds.
Adam P.Sourcing Manager · France
★★★★★
Inconel 600 wire supplied to spec; MTC documentation matched our project requirements. Everything organized.
Nham Q.Project Engineer · Vietnam
★★★★★
Timely updates and quick responses made the purchasing process much easier on our side.
Ashlea Q.Procurement Lead · United States
★★★★★
Finding nickel alloy capillary tubing with such a small diameter is not easy; your alternatives helped us evaluate options fast.
Sentek R&D TeamSouth Korea
10 — Get your price

Send us a spec. We'll send back a certified quote in 24 hours.

Grade · OD · WT · length · quantity · standard. That's all we need. Full datasheet, heat availability, CIF pricing to your port — back in one business day.

Request certified quote → info@truegrademetals.com
No obligationNDA on requestISO 9001 / EN 9100 supplierEN 10204 3.1 MTC
11 — FAQ

Sourcing-agent questions, answered.

Can't find your answer? Our engineers respond to technical inquiries within 24 hours — speak to a metallurgist.

What is the standard length? Can tubes be cut?

Standard: 1 m or 6 m for overseas orders; 12 m / 24 m on request. Cut lengths incur extra cost — specify the method (laser / plasma / waterjet) in your inquiry.

Can you polish nickel-alloy seamless tubes?

Yes. Polished, pickled, sand-blasted and bright-annealed finishes are all standard options. Polished tube ships in wooden cases by default to protect the surface.

Do you supply matching fittings?

Yes — elbows, tees, reducers, caps and stub ends per ASTM B366, matched to your tube heats so the full system carries one traceable documentation package.

What is the lead time?

Stocked heats ship in days. Made-to-order seamless tube typically runs 30–45 days depending on grade and size. A hard delivery date is fixed at PO acceptance — backed by our on-time guarantee.

Seamless vs. welded — which do I need?

Seamless has no weld seam, giving uniform strength and corrosion performance in extreme pressure, temperature and corrosive service. Welded tube is more economical for mild duty. Tell our engineer your service conditions and we'll recommend honestly.

Can you deliver MTC EN 10204 3.1 / 3.2?

3.1 is standard on every heat at no extra cost. 3.2 with third-party witness (BV, SGS, TÜV) is available on request — we coordinate the inspection before shipment.