Product family 01 / Steel pipes

Pipe and tube supply,
matched to the line.

Carbon steel, alloy steel, seamless, precision, mechanical and structural pipe forms for industrial buyers. Grade, outer diameter, wall thickness, length and end use are confirmed together before quotation.

Request this product family Back to products

Technical data, process & buyer resources ↓

01Grade / standard

02OD × wall × length

03Cut, end or surface work

04Document and packing scope

Steel pipes — Product viewRUNSU / reference

Product range

Pipe forms for the next operation.

The family name is only a starting point. The tube route, surface condition and downstream use determine which details should be fixed before a quotation.

01Seamless steel pipesSeamless
02Carbon steel pipesCarbon
03Alloy steel pipesAlloy
04Precision steel tubesPrecision
05Mechanical steel tubesMechanical
06Structural steel pipesStructural
07Boiler & pressure steel pipesPressure
08Cut-to-length steel pipesCut-to-length

Specification, without assumed stock sizes.

This table shows the original grade references and the points to confirm. It does not promise a fixed size range or imply that every grade is available in every pipe form.

Steel pipe inquiry framework. OD, wall thickness and length are inquiry-defined.
Product form	Original grade references	Size basis	Coordination points
Carbon steel pipes	20#, 45#, Q235, Q355	OD, wall thickness and length as stated in the inquiry	Cut-to-length, surface cleaning and packing preparation
Alloy steel pipes	20Cr, 40Cr, 35CrMo, 42CrMo	OD, wall thickness and length as stated in the inquiry	Heat-treatment and inspection requirements confirmed per order
Seamless steel pipes	Grade or standard to be confirmed	OD, wall thickness and length as stated in the inquiry	Seamless route, dimensional check and document review
Precision steel tubes	Grade to be confirmed	Dimensions and tolerance agreed from the inquiry	Surface, tolerance and machining preparation as agreed
Mechanical steel tubes	Grade to be confirmed	OD, wall and length defined by the order	Machining support and packing
Structural steel pipes	Q235, Q355	OD, wall and length defined by the order	Length, marks and packing
Boiler & pressure steel pipes	A106 Gr.B, A53, API 5L references	Standard and dimensions confirmed per inquiry	Standard edition and document requirements confirmed before quote
Cut-to-length steel pipes	Supplied grade to be confirmed	Length defined by the order; OD and wall as requested	Cutting, end processing where agreed, and packing

No stock size range is implied by this page. Availability, tolerances and documentation are confirmed against the actual inquiry and agreed order.

Grade references

Additional references named in the source material include 1020, 1045, 4130, 4140, EN8, EN19, E355 and S355. They are discussion points only until matched to the product form, standard edition and application. A grade name does not confirm availability or automatic equivalence.

TECHNICAL / BUYER REFERENCE

Technical data & buyer resources

Use these public technical references to define an order. They do not state RUNSU stock, batch test results or committed machining capacity. Grade and delivery-condition limits accompany the data.

Specify application, standard and dimensions together

Choose the specification around the application
Reference	Product focus	Add to the RFQ
ASTM A519/A519M	Seamless carbon/alloy tubing for mechanical use	Grade, hot/cold finish, controlling dimensions and tolerances
ASTM A106/A106M	Seamless carbon pipe for elevated-temperature use	Grade, dimensional system, design and test requirements
ASTM A53/A53M	Pipe specification covering welded and seamless routes	Manufacturing route, grade, surface and ends
EN 10305-1	Seamless cold-drawn precision tube	Grade, delivery state and critical dimensions

A mechanical-tubing specification alone does not establish suitability for a pressure design. Confirm the grade, standard edition and acceptance terms.

ASTM · A519/A519M ↗ · ASTM · Steel standards ↗

Material data with a defined condition

Published E355 +N reference · Mannesmann · EN 10305-1
Property	Reference
Yield strength	≥ 355 MPa
Tensile strength	490–630 MPa
Longitudinal elongation	≥ 22%
C / Si / Mn · maximum mass fraction	0.22% / 0.55% / 1.60%
P / S · maximum mass fraction	0.025% / 0.025%

Producer-published grade references, not RUNSU batch results. Dimensional and delivery-condition restrictions can apply; the purchase specification and material certificate govern acceptance.

Mannesmann · E355 +N / EN 10305-1 ↗

One grade can have different delivery states

Precision-tube delivery designations
Code	Meaning	Buyer check
+C	No heat treatment after final cold working	Do not assume normalized ductility
+SR	Stress relief after cold working	Specify dimensional and mechanical requirements together
+A	Annealed	Consider subsequent forming and machining
+N	Normalized	Condition used for the E355 +N data above

Mannesmann · Precision tube delivery conditions ↗

Typical route and inspection checkpoints

01
Select the starting route
Seamless tube starts with a hot-worked solid billet; welded tube starts with formed strip. Specify if seamless construction is essential.
02
Confirm precision and condition
Cold drawing, where required, further controls tube dimensions. Select the final delivery state.
03
Cut length and finish ends
Specify length variation, end preparation, burr removal and protection.
04
Inspect and trace
Check actual OD, wall, length and appearance. Match heat identity and material documents to the order.

A planning reference: the actual manufacturing route and tests are agreed during quotation.

Mannesmann · Manufacturing processes ↗

Theoretical weight calculator

Estimate material and shipping mass using 7,850 kg/m³. Actual dimensions, grade and packaging affect shipment mass; weighing and order terms govern.

kg/m = π / 4 × [D² − (D − 2t)²] × 0.00785
Total kg = kg/m × length × quantity; D and t in mm, length in m. Packaging and machining losses excluded.

SSAB · Steel density ↗

References checked 19 October 2026. The agreed standard edition, drawing, technical agreement and material certificate govern supply and acceptance.

Processing coordination

Processing options, confirmed in sequence.

Pipe processing is arranged against the order rather than offered as a blanket list. Each step is tied to the dimension, surface or documentation requirement it serves.

Cutting, surface and treatment requirements are confirmed against the product form.
Inspection points are named before work begins, not added after dispatch.
Any requirement outside the agreed scope is reviewed before it is accepted.

Cutting

Cut-to-length preparation against the confirmed order length.

End processing

End preparation where specified and agreed.

Surface

Cleaning or basic surface preparation for the agreed condition.

Heat treatment

Support coordinated when the specified grade and route require it.

Inspection

Dimensional, visual and document checks within the agreed scope.

Packing

Export packing prepared for the size, weight and transport route.

Applications

Where the pipe family fits.

Pipe inquiries are reviewed around the function of the tube and the condition required at delivery.

Review quality control scope

Machinery parts and equipment frames
Construction machinery components
Energy and industrial equipment
Structural and fabrication work
Precision assemblies
Project material supply
Cut-to-length production stock
General industrial maintenance

Procurement FAQ

Pipe procurement questions

Clarify these points before quoting so the technical and commercial reviews start from the same information.

What pipe dimensions should I provide?

Give the outer diameter, wall thickness and length required. Add the tolerance, standard and end use if available. All dimensions are treated as inquiry-defined; no fixed stock range is assumed.

Can you discuss ASTM, API, EN, DIN, GB or JIS standards?

Yes, these standards can be part of the requirement discussion. The exact standard, edition and acceptance points must be stated in the inquiry and confirmed before quotation.

How are grade equivalents handled?

They are compared, not automatically substituted. Chemistry, mechanical properties, heat-treatment condition and product form are checked before any alternative is proposed.

Can the pipe be cut before shipment?

Cut-to-length supply can be discussed. Provide the finished length, allowable tolerance and packing preference so the cutting and packing route can be evaluated together.

Send the pipe line.
We will check the route.

Include grade or standard, OD, wall thickness, length, quantity, processing requirement and destination. Add drawings or technical documents when available.

Start an RFQ Explore all product families

Pipe and tube supply,matched to the line.