ASTM B622 / ASME SB-622 / UNS N06455 / W.Nr. 2.4610
Thaida Stainless Steel Manufacturing (Thailand) Co., Ltd. manufactures ASTM B622 Alloy C4 seamless pipes at Ban Bueng, Chonburi, Thailand, and dispatches them from Bang Phli, Samut Prakan, to acid handling and pulp bleaching plants across the region. The alloy carries the UNS number N06455 and the European number W.Nr. 2.4610, and the grade sits inside our Hastelloy Seamless Pipes range. Each length carries its heat number and nominal size, on the pipe body or on the bundle tag, which a receiving store checks first.
Alloy C4 seamless pipeUNS N06455 / W.Nr. 2.4610
EN 10204 3.1 certificate / 3.2 on request
Every figure below comes from the production range we hold for this grade. Match it against your line list before you send sizes.
ASTM B622, and ASME SB-622 alongside it, covers seamless nickel and nickel-cobalt alloy pipe and tube, and it names these alloys by UNS number alone rather than by any grade designation, so N06455 is what we stamp and certify. A pipe item is written as a nominal pipe size with a schedule, which is the ordering basis the specification gives pipe; where a bundle is dimensioned by outside diameter and wall instead, our Alloy C4 seamless tubes cover the same alloy. Each length leaves the works solution annealed and descaled, and descaling is not needed where the anneal runs under atmosphere control.
One chemical analysis and one tension test cover each lot, and no length goes out until it has passed a hydrostatic pressure test or, in its place, a nondestructive electric examination. The lot certificate for an ASME SB-622 C4 seamless pipe is EN 10204 3.1 (3.2 on request), and we add an independent inspection report where the order calls for one.
Nickel is the balance in a seamless Alloy C4 pipe, with chromium and molybdenum in near-equal amounts and a titanium limit that no other grade in the family carries.
Molybdenum from 14.0 to 17.0 % carries the resistance to reducing acids, chromium from 14.0 to 18.0 % covers the oxidizing side, and carbon capped at 0.015 % holds back carbide precipitation at grain boundaries. Titanium is limited to 0.70 % maximum on this grade and on no other in the range. Iron stays at 3.0 % maximum, and ASTM B622 sets no tungsten requirement for the alloy.
The table gives the ASTM B622 limits. The analysis of the heat you receive is listed on the certificate that travels with the material.
UNS N06455C4
| Element | Limit per ASTM B622 / ASME SB-622 (%) |
|---|---|
| Ni (Nickel) | Balance |
| Cr (Chromium) | 14.0 to 18.0 |
| Mo (Molybdenum) | 14.0 to 17.0 |
| Fe (Iron) | 3.0 max |
| Co (Cobalt) | 2.0 max |
| Mn (Manganese) | 1.0 max |
| Ti (Titanium) | 0.70 max |
| Si (Silicon) | 0.08 max |
| P (Phosphorus) | 0.04 max |
| S (Sulfur) | 0.03 max |
| C (Carbon) | 0.015 max |
| W (Tungsten) | No requirement |
These are room-temperature minimums, and ASTM B622 applies one set of them to pipe and tube alike.
| Property | Value | Unit |
|---|---|---|
| Tensile Strength, min | 690 (100) | MPa (ksi) |
| Yield Strength (0.2% offset), min | 276 (40) | MPa (ksi) |
| Elongation in 2 in. (50.8 mm) or 4D, min | 40 | % |
The 276 MPa yield minimum is the lowest of the C-family grades we draw, against 283 MPa for N10276 and 310 MPa for N06022 in the same table, so a wall calculation on this alloy starts from a lower material input. There is no split by wall thickness either, so the one row of minimums above covers every size we produce.
Alloy C4 carries fewer regional designations than the other grades in the family. The entries below are cross-references for drawing control, and conformity is held against ASTM B622 / ASME SB-622 alone.
UNS N06455 is the only designation ASTM B622 itself assigns, and it is the number marked on the material and stated on the certificate. W.Nr. 2.4610, written DIN 2.4610 on older drawings, identifies the same alloy in European practice. We quote it beside the UNS number when a drawing calls for a seamless 2.4610 pipe, and claim no conformity to a European standard.
Our envelope for seamless 2.4610 pipe runs 6 to 457 mm on the outside diameter, 1 to 65 mm on the wall, and up to 18 m on the length, with fixed cuts where a line list needs them. Items are confirmed as a nominal pipe size with its schedule, so mark the schedule or the wall thickness against each line on your inquiry. Both ends come plain, cut and deburred.
Every seamless WNR 2.4610 pipe we release is measured against the ASTM B622 cold-worked tolerances. The rows set out below are the process-pipe diameters this grade is usually ordered in, and which wall column governs an item follows from whether the line was bought to nominal wall or to minimum wall.
| Nominal OD (mm) | OD tolerance (mm) | Nominal wall, % | Minimum wall, % |
|---|---|---|---|
| Over 38 to 76, incl | ±0.25 | ±10.0 | +22 / 0 |
| Over 76 to 114, incl | ±0.38 | ±10.0 | +22 / 0 |
| Over 114 to 152, incl | ±0.51 | ±12.5 | +28 / 0 |
| Over 152 to 168, incl | ±0.64 | ±12.5 | +28 / 0 |
| Over 168 to 219, incl | ±0.79 | ±12.5 | +28 / 0 |
| Over 219 to 356, incl | +1.57 / -0.79 | +15.0 / -12.5 | +30.0 / 0 |
| Over 356 to 610, incl | +3.18 / -0.79 | +15.0 / -12.5 | +30.0 / 0 |
Swipe sideways to see the full table.
The two largest rows print the boundaries the tolerance table itself uses, so they reach past the 457 mm top of our envelope. Diameters below 38 mm are held tighter again, and a quotation names the band each ordered size falls in.
ASTM B622 carries the identification rules through to the pipe body and to the package, and they are worth knowing before a consignment arrives, because they set out exactly what a receiving store can verify without opening the certificate file.
| Where the marks appear | What is marked |
|---|---|
| Each piece 19.0 mm (3/4 in.) outside diameter and larger that is also longer than 914 mm (3 ft) | Manufacturer name or brand, material name or UNS number, the letters ASTM, the specification number, heat number and nominal size |
| Each piece smaller than 19.0 mm outside diameter or shorter than 914 mm | The same information on each piece, or on a tag securely attached to the bundle or box it ships in |
| The package, or a label or tag attached to it | Material name or UNS number, heat number, condition, the letters ASTM, the specification number, nominal size, gross, tare and net weight, consignor and consignee addresses, and the order number |
The method matters as much as the content: marking has to be applied by a means that will not cause harmful contamination, so identification on a seamless nickel alloy C4 pipe leaves the surface fit for the acid duty it was bought for. Keep the bundle tag with short lengths and small-bore pieces until they are installed, since those carry their identity on the tag rather than on the pipe body.
Seamless Alloy C4 pipe is specified where contaminated mineral acids, organic acids, chlorides, seawater and brine run through lines that were welded in position and cannot be solution annealed afterwards.
Transfer lines and header piping carrying aggressive acids and halides into reaction vessels, evaporators and exchanger shells sit in the core duty for the alloy, especially in multipurpose plants that change product.
Organic acid plants run C4 seamless pipe into process piping, acid transfer headers and reboiler circuits, where formic and acetic acid streams strip the passive film from austenitic stainless lines.
Absorption towers, storage tank connections and the runs between them take UNS N06455 seamless pipe in hydrochloric acid service, where chloride concentration and low pH together rule out stainless steel.
Pickling tank pipework and titanium dioxide process lines carry mixed acid at concentration, and a seamless WNR 2.4610 pipe holds up where carbon steel and austenitic stainless lines corrode through.
Bleach plant and effluent piping moving acidic or chloride-bearing pulp and waste streams is a long-running use, and the grade also serves scrubber, damper and stack liner connections in pollution control.
Aircraft exhaust and fuel system pipework uses Alloy C-4 seamless pipe in small bores, where thermal cycling and condensate chemistry together decide how long a line lasts.
Specify this grade when a fabricated spool has to enter acid service in the as-welded condition. The low iron ceiling and the absence of a tungsten requirement cut back the intermetallic phases that form while welding and during heat treatment, which is why the heat-affected zone keeps its corrosion resistance without a post-weld solution anneal.
Where the duty swings into strongly oxidizing media, Alloy C22 seamless pipes are the alternative, and ASTM B622 gives N06022 a higher 310 MPa yield minimum and a 45 % elongation minimum. Where one alloy has to cover mixed oxidizing and reducing service, Alloy C276 seamless pipes add 3.0 to 4.5 % tungsten and 4.0 to 7.0 % iron to a similar molybdenum base. C4 trades that breadth for the simpler and more stable composition, and it earns its place when the welding sequence, rather than the medium, is the hardest part of the job.
Every seamless alloy 2.4610 pipe leaves the works packed for sea freight.
Packing
Bundles or wooden cases, with caps protecting the plain cut ends.
Identification
Heat number and nominal size stay readable on the pipe body, or on the bundle tag for short and small-bore lengths.
Trade terms
FOB, CIF or CFR to the port named on your order.
Documents
The EN 10204 3.1 (3.2 on request) certificate, a dimensional and surface measurement record, heat treatment charts for the lot, and the raw material certificate.
Reports we can add to the manufacturer test certificate: 100% PMI, impact, bend, grain size, pitting corrosion, intergranular corrosion, the hydrostatic test record, eddy current (ET) and ultrasonic (UT) results.
Dispatch
Confirmed with the quotation against the delivery date on your order.
Seamless alloy 2.4610 pipe is indicatively priced at around USD 25 to 62 per kg. Read that as an opening band rather than a quotation: C4 is a small-volume grade, and the figure for a given item moves with outside diameter, wall thickness, schedule, cut length, order quantity and the testing specified, and it tracks nickel and molybdenum input costs. Send your size list and we will price each line.
Indicative only. Send your sizes and specification to Thaida for a firm quotation.
We manufacture at 154 Moo.1 Map Phai, Ban Bueng, Chonburi 20170, Thailand. Quotations, order handling and documentation come from the office at 89/18 Moo.15 Enterprize Park, Bangna-Trad Road, Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand. Plants across Thailand are supplied direct, and consignments are shipped to Singapore, Malaysia, Vietnam, Indonesia, the Philippines and India.
On the 25 mm pieces it is marked on the pipe body, because they clear 19.0 mm outside diameter. The 12 mm pieces may instead carry it on a tag attached to their bundle or box, so reconcile those against the tag rather than the pipe body.
They carry the same marks a larger piece gets, so nothing in the identification is lost: the marks are applied either to each piece or to a tag securely attached to the bundle or box.
No single piece under 19.0 mm outside diameter or under 914 mm long has to be marked individually: the choice between marking each piece and tagging the bundle or box is the manufacturer's. State on the order if you need every piece marked and we will mark them.
ASTM B622 sets no tungsten requirement for N06455 and caps its iron at 3.0 %, while the N10276 row prints 3.0 to 4.5 % tungsten and 4.0 to 7.0 % iron against a comparable molybdenum range. N06455 also carries a titanium limit of 0.70 % maximum, which N10276 does not.
Give the nominal pipe size and the schedule, or the outside diameter and wall where your line list is dimensioned that way, with the cut length and quantity per item. The envelope is 6 to 457 mm outside diameter, 1 to 65 mm wall, and lengths to 18 m.
It is the specified minimum 0.2 % offset yield strength under ASTM B622, and it is the material input your design code works from. It is the lowest of the C-family grades, so a C4 line can call for a heavier wall than the same line in C276 at 283 MPa.
The heat analysis compared with the ASTM B622 limits, the lot tension result, and a statement that the pressure or electric test was carried out on each length. It is issued as EN 10204 3.1 (3.2 on request), and UNS N06455 appears on it.
Request a Quote for Alloy C4 Seamless Pipes
or email sales@thaida.co.th
