Is seamless tube always more expensive than welded?

On common grades and diameters (304L/316L), the gap can be small, even nil depending on available stock — that is exactly what SPS compares before quoting, without systematically favouring either one.

Why do you call this page a priority?

Because it's where SPS's sourcing edge is sharpest: European agreements on everyday grades and direct mill sourcing on rare ones meet on this single product line.

Is seamless tube affected by any import regulation?

Yes, explicitly: seamless stainless tubes are named by NC code in EU safeguard regulation 2026/1384 (7304 11 00, 7304 22 00, 7304 24 00, 7304 41 00, 7304 49 83/85/89) and in the CBAM mechanism. See the steel import regulation cluster.

Can I get a welded-vs-seamless comparative quote on my reference?

Yes, mention it in your quote request — SPS prices both options when the applicable standard allows it.

STAINLESS TUBES · SEAMLESS

Seamless stainless tube

Seamless stainless tube is where SPS's sourcing edge is sharpest: European agreements on everyday grades, direct mill sourcing on rare ones. No longitudinal joint, extruded or drawn, in the same dimensional ranges as welded tube.

Request a quote

Dimensional table

Wall thickness (mm) by series, per ASME B36.19M — excerpt, SCH 5S column omitted
NPS	DN	OD (mm)	SCH 10S (mm)	SCH 40S (mm)	SCH 80S (mm)
1/8	6	10.3	1.24	1.73	2.41
1/4	8	13.7	1.65	2.24	3.02
3/8	10	17.1	1.65	2.31	3.2
1/2	15	21.3	2.11	2.77	3.73
3/4	20	26.7	2.11	2.87	3.91
1	25	33.4	2.77	3.38	4.55
1 1/4	32	42.2	2.77	3.56	4.85
1 1/2	40	48.3	2.77	3.68	5.08
2	50	60.3	2.77	3.91	5.54
2 1/2	65	73	3.05	5.16	7.01
3	80	88.9	3.05	5.49	7.62
4	100	114.3	3.05	6.02	8.56
5	125	141.3	3.4	6.55	9.53
6	150	168.3	3.4	7.11	10.97
8	200	219.1	3.76	8.18	12.7
10	250	273	4.19	9.27	12.7
12	300	323.8	4.57	9.53	12.7
14	350	355.6	4.78	—	—
16	400	406.4	4.78	—	—
18	450	457	4.78	—	—
20	500	508	5.54	—	—
24	600	610	6.35	—	—

My dimension isn't listed → · See the full table →

What is seamless stainless tube?

Seamless stainless tube is made by piercing then extruding a solid billet, or by successive cold drawing, with no welding operation at all. This lack of a joint is why it is frequently specified in the most demanding specifications — high pressure, thermal cycling, severe corrosive media — even though most standard applications are equally well covered by welded tube.

How to choose it?

Seamless is required when a standard, a customer or a service pressure explicitly demands it. Outside those cases, it's more a matter of perceived robustness than a systematic technical necessity — compare it with welded tube (cheaper) on its dedicated page. This is where SPS's condition comparison has the most value: on everyday 304L/316L, where welded performs just as well for less.

Available grades

304L, 316L, 316Ti, 321H and 310S in seamless directly benefit from SPS's European sourcing agreements — this is where the price gap with competitors is sharpest. On request, duplex 2205/2507, super austenitic 904L/254 SMO, nickel alloys (625, 825, C-276) and titanium Gr2/Gr7 are sourced in seamless.

My grade isn't listed →

Applicable standards

ASTM A312
ASTM A269
ASTM A213
EN 10216-5

Partner stock or mill?

Seamless is the page where comparing partner stock and a mill purchase makes the most sense: on everyday grades, the price gap plays out here.

From partner stock: 48 hours for urgent needs, 5 working days as standard.

We go through the mill when volume and lead time make sense — typically container-load quantities, sometimes less, with a lead time of a few months including transport. That arbitration is ours to make: when buying at source works out cheaper for you, we say so.

Frequently asked questions

Is seamless tube always more expensive than welded?: On common grades and diameters (304L/316L), the gap can be small, even nil depending on available stock — that is exactly what SPS compares before quoting, without systematically favouring either one.
Why do you call this page a priority?: Because it's where SPS's sourcing edge is sharpest: European agreements on everyday grades and direct mill sourcing on rare ones meet on this single product line.
Is seamless tube affected by any import regulation?: Yes, explicitly: seamless stainless tubes are named by NC code in EU safeguard regulation 2026/1384 (7304 11 00, 7304 22 00, 7304 24 00, 7304 41 00, 7304 49 83/85/89) and in the CBAM mechanism. See the steel import regulation cluster.
Can I get a welded-vs-seamless comparative quote on my reference?: Yes, mention it in your quote request — SPS prices both options when the applicable standard allows it.