What's the difference between welded and seamless tube?

Welded tube is formed from a rolled strip then longitudinally welded; seamless tube is extruded or drawn with no joint. Seamless is often preferred for high pressure or strict specifications, but welded covers most standard piping uses at a lower cost.

Do you supply non-standard lengths?

Yes. Under 6 m, cut-to-length is available with a -0/+5 mm tolerance. Beyond 6 m, cutting is studied on request, sometimes during production.

Is stainless tube affected by any import regulation?

Seamless stainless tubes are explicitly named in EU safeguard regulation 2026/1384 and in the CBAM mechanism. See the steel import regulation cluster for the detail by NC code.

Can I order a tube in a grade that isn't listed on this page?

Yes — the grades listed are examples, not a closed catalogue. Describe your need in a quote request; a simple request gets a same-day reply.

STAINLESS STEEL TUBES

Stainless steel tubes

Welded and seamless stainless tubes, from everyday 304L/316L to rare grades in small quantities. Six tube families, from partner stock in 5 working days to volume planned through the mill, in ASTM and EN dimensions, with material certificates checked before shipment.

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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 stainless steel tube?

A stainless tube is a hollow, circular-section profile, produced either by longitudinal welding (welded tube) or by extrusion/drawing with no seam (seamless tube). Both processes cover the same grade range; the choice depends on service pressure, diameter and budget, not a quality hierarchy.

How to choose it?

The first criterion is the process: welded for most standard piping applications, seamless when service pressure or the specification calls for it. The second is use case: heat exchanger tube for a tube bundle, U-tubes for a bent bundle, polished sanitary tube for product contact, precision redrawn tube for tight dimensional tolerance. The six sub-pages below detail each case.

In this pillar

Welded stainless tube Welded stainless tube covers most process piping uses: 304L and 316L from partner stock, r… Seamless stainless tube Seamless stainless tube is where SPS's sourcing edge is sharpest: European agreements on e… Stainless heat exchanger tube Heat exchanger tube equips the tube bundles of steam generators, condensers and process ex… Stainless U-tubes U-tubes are heat exchanger tubes bent into a hairpin, on request — not a standard partner-… Polished sanitary stainless tube Polished sanitary tube meets product-contact requirements in food and pharma: controlled s… Precision redrawn stainless tube Precision redrawn tube goes through one or more additional cold-drawing passes after extru…

Available grades

Austenitic grades (304L, 316L, 316Ti, 321H) cover most partner-stock requests. On request, SPS also sources duplex and super duplex, super austenitic, nickel alloy, titanium, ferritic/martensitic and heat-resistant grades — nine families in total, none out of reach as a matter of principle.

My grade isn't listed →

Applicable standards

The standards base for stainless tube covers the main ASTM and EN process piping standards, plus sanitary standards (DIN, SMS, ISO) for food-grade uses.

ASTM A312
ASTM A269
ASTM A213
ASTM A249
ASTM A270
EN 10216-5
EN 10217-7
DIN 11850 Reihe 2
SMS 3008
ISO 2037
ISO 1127

Partner stock or mill?

Stainless tube best illustrates SPS's two routes: from a single metre off partner stock to a planned mill order.

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

What's the difference between welded and seamless tube?: Welded tube is formed from a rolled strip then longitudinally welded; seamless tube is extruded or drawn with no joint. Seamless is often preferred for high pressure or strict specifications, but welded covers most standard piping uses at a lower cost.
Do you supply non-standard lengths?: Yes. Under 6 m, cut-to-length is available with a -0/+5 mm tolerance. Beyond 6 m, cutting is studied on request, sometimes during production.
Is stainless tube affected by any import regulation?: Seamless stainless tubes are explicitly named in EU safeguard regulation 2026/1384 and in the CBAM mechanism. See the steel import regulation cluster for the detail by NC code.
Can I order a tube in a grade that isn't listed on this page?: Yes — the grades listed are examples, not a closed catalogue. Describe your need in a quote request; a simple request gets a same-day reply.

Piping doesn't stop at the tube