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What EN 10216-2 covers

EN 10216-2 is the part of the EN 10216 series that deals with seamless tubes of non-alloy and alloy steels with specified elevated-temperature properties. It is used for boilers, superheaters, heat exchangers, process piping and pressure equipment. The tubes are normally supplied to the European Pressure Equipment Directive framework, so the standard is often paired with EN 13480 (industrial piping) or EN 12952 (water-tube boilers) in design work.

The grade names tell you how each steel is classified. The letter P stands for pressure purposes, the number gives the specified minimum yield strength in the old system, and GH means elevated-temperature use. Names such as 16Mo3, 13CrMo4-5 and 10CrMo9-10 follow the alloy-steel naming rules of EN 10027-1, where the figures relate to carbon content and alloy content.

The five grades in practice

• P235GH and P265GH: non-alloy carbon-manganese steels. They are the usual choice for steam, hot water and general process lines at moderate temperatures. P265GH has a higher strength level than P235GH.
• 16Mo3: carbon steel with about half a percent of molybdenum, which improves creep strength at higher temperatures. Long-term exposure to very high temperatures can cause graphitization, which is one reason designers often favour chromium-molybdenum grades instead.
• 13CrMo4-5: a 1Cr-0.5Mo steel with better creep and oxidation resistance than 16Mo3.
• 10CrMo9-10: a 2.25Cr-1Mo steel for higher temperatures and more demanding service, including hydrogen-containing or oxidizing environments, subject to the relevant design rules.

Approximate equivalents

Equivalents are only a guide. Chemistry limits, heat treatment and testing rules differ, so never treat two grades as interchangeable without checking both standards and, where applicable, the design code.

For ferritic alloy pipe in ASME projects, the ASME Section II counterpart of ASTM A335 is SA-335. The related Australian reference for pressure piping is AS 4041, which sets design requirements rather than replacing the material standard.

What to check in the standard

The chemical composition limits, mechanical properties at room and elevated temperature, and permitted delivery conditions are listed in the material tables of EN 10216-2 itself. Because values vary between editions, always take them from the edition named in your purchase order. Also read:

• the manufacturing and heat treatment clauses (normalized, or normalized and tempered, depending on grade);
• the test category: test category 1 or 2 determines the extent of non-destructive and other testing;
• the options list, where you select extra requirements such as impact testing or additional checks;
• the inspection document clauses, which refer to EN 10204.

Documentation and certificates

EN 10204 type 3.1 certificates are the usual minimum for pressure service, with type 3.2 used where a third party or purchaser's inspector must countersign. Cast number, heat treatment, dimensions and test results should be traceable to the marking on the tubes. Dimensional tolerances are in EN 10216-2, while preferred outside diameters and wall thicknesses are found in ISO 1127 and EN 10220.

Welding and fabrication notes

Chromium-molybdenum grades need controlled preheat, matching filler metals and post-weld heat treatment. The requirements depend on wall thickness and design code, so follow the approved welding procedure per EN ISO 15614-1 or ASME Section IX. Carbon steel grades are more forgiving but still require qualified procedures for pressure work.

Buyer's checklist

• State the standard with part number and edition year: EN 10216-2 plus grade.
• Specify the delivery condition and test category.
• Define outside diameter, wall thickness and tolerance class, and length (random or fixed).
• Select the inspection document under EN 10204, 3.1 or 3.2.
• List optional requirements, such as impact tests or extra non-destructive testing.
• Confirm the design code and temperature used for wall thickness calculation.
• If substituting an ASTM or other grade, get written approval from the designer or inspector.
• Check marking, packing and corrosion protection for the shipping route.