Boiler tubes - for pressure equipment, used at higher temperatures

Standards and steel grades,
Tube sizes acc. to EN, DIN, BS, NF A, UNI, STN, ČSN and PN-H standards,
Tube sizes acc. to GOST and TU standards,
Tube sizes acc. to ASME standard,
Tube sizes acc. to ASTM standard,
Tube sizes acc. to JIS standard,
Precision tubes sizes.

Tubes for pressure use can be found in many areas of industry. The possibilities of using the individual groups of tubes from the point of view of the pressure level, temperature level and the kind of medium they transfer is set in the appropriate guidelines for pressure equipment and the corresponding standards for the individual tubes. The tubes are supplied either as hot rolled or cold drawn. Standards, dimensions and the steel grades are shown in a separate overview.

Tube dimensions and tolerances for pressure equipment

The tube dimensions range from 10.2 mm to 139.7 mm, starting with 26.9 mm diameter, wall thickness from 2.6 mm are supplied as hot rolled. Tubes of smaller diameters and the thick wall tubes of larger diameters are supplied as cold drawn and subsequently they are heat treated. Tubes in this condition are supplied based on the agreement at the time of placing the order only. Tubes dimensions correspond to the following requirements: EN 10216-1, DIN 2448, BS 3600, NF A 49-112, NF A 49-210, UNI 7287, STN 42 5715, STN 42 5716, ČSN 425715, ČSN 42 5716, GOST 8732, PN-H 74219, ASTM A53, ASME SA53, JIS G 3454 and JIS G3455. Detailed dimensional overview is shown in the tables according to EN, DIN, BS, NF A, UNI, STN, ČSN and PN-H standards, GOST standards, TU standards, ASME standards, ASTM standards, JIS standards and standards for precision tubes.

Steel for tubes that are destined for pressure and thermal equipment

The tubes are predominantly made of the following steels, according to EN 10216-1: P195TR1, P235TR1, P265TR1, P195TR2, P235TR2, P265TR2; and ASTM A 53: Grade A, Grade B. Other steel grades according to DIN 1629, DIN 1630, BS 3601, NFA 49-112, NF A 49-210, UNI 7287, GOST 8731, PN-H74219, JIS G3454 and JIS G3455 and its chemical composition and mechanical properties are shown in a separate overview.

Tubes length for pressure equipment

Diameter (OD) [mm]Wall (WT) [mm]Length (L) [mm]
OD < 60,3 5 – 6
OD => 60,3 WT < 7,15 – 6 or 10 – 14
WT => 7,15 – 6
The types of supplied tubes length: (a) random, (b) fixed ± 500 mm, (c) exact +15 / -0 mm.

Tube straightness

Permitted straightness is set as 0.0015 multiple (0.0015 x L) of the overall tubes length, for a one meter length the permitted straightness is 3 mm.

Tube ends for pressure equipment

The ends of the tubes are vertical to the longitudinal axis and are without burrs.

Condition of the tubes surface

Condition of the tubes meets the requirements of the appropriate standards, i.e. the tubes go through normalized forming or after the cold forming goes the normalized annealing. The tube surface meets the standards’ requirements and the means of manufacturing.

Markings of the tubes and tube bundles

The tubes with the outside diameter up to 51 mm may be marked by a label attached to the tube bundle. Larger tubes must have markings at least at one end of the tube with the necessary data.

Tubes surface protection for pressure equipment

The means of a temporary protection of the tubes surface for transportation and storage is necessary to agree upon when placing the order. The tubes may be supplied without the temporary preservatives of the surface or with surface protection by a preservative that was agreed upon.

Tube packaging for pressure equipment

The tubes are supplied in packages with a circular or hexagonal diameter with having weight of 300 to 3500 kilograms. The tubes are tied with a steel band. Tubes can be packed into a plastic foil, burlap or wooden crate upon request.

Tube testing for pressure equipment

The group of TR1 quality is usually tested by a nonspecified test. The group of TR2 quality is always tested by a specified test. The main difference in the mandatory testing between the TR1 and the TR2 is the fact, that in the TR2 quality the testing is done by blow bending test at 0°C temperature and as the optional test at this quality it can be agreed to do the nondestructive test as a proof of longitudinal defects.

Certified test reports

Certified test reports are issued according to the appropriate TDC standards:
EN 10204, pre EN 10294 - 1 certificate 3.1.B, for EN 10297 - 1 Certified test reports : (a) nonspecified testing (only the mandatory tests) 2.2, specified testing – 3.1.B or other types of Certified test reports according to an agreement (3.1.A, 3.1.C, 3.2)
STN 42 0250, ČSN 42 0250
DIN 50049, 2.2 or 3.1.B or other after an agreement
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