Tubes suitable for welding and threading
Standards and steel grades,
Tube sizes acc. to EN 10224 standard,
Tube sizes acc. to ASTM or ASME standards.
Tube sizes acc. to DIN, BS, NF A, UNI, STN, ČSN, GOST, PN-H standards,
Seamless steel tubes for threading and welding are produced by hot rolling. Continuously cast blooms are semi-finished product that is used as the starting material for these tubes. Threaded tubes have a wide range of use especially in the construction field. They are used for water transfer and distribution of all kinds of liquids and gasses. The limits for using this group of tubes as far as the level of pressure is concerned and the type of transfer media is used are given by the appropriate directives that are valid for pipeline construction, distribution and pipes. Tubes are made from carbon and alloyed steel. Overview of dimensional standards and technical-delivery conditions by which these tubes are manufactured and supplied is shown in a separate overview.
separate overview. Steel is made in electric arc furnace and is fully killed. After an agreement other types of steel may be supplied.
Delivery and surface condition for tubes for threadingUsually the tubes are supplied as hot rolled. Only tubes with DN 6 -10, or possibly tubes of other dimensions may be supplied after an agreement as cold drawn tubes, and after forming, heat treated. Surface of the tubes is appropriate to the way of production. Upon request, tube surface may be taken care of by a definite surface insulation (tar, PVC tape or extruded PVC according to DIN 30670).
Length of the tubes destined for threading and weldingTubes are supplied in approximate length of 6 meters ± 500 mm, or in precise length of 6 meters –0/+15 mm after an agreement.
Straightness of the tubes for threadingTubes visually are straight.
Tube ends for threadingTubes are supplied with smooth ends without thread and sockets.
Marking of the tubes and tube bundlesTubes are marked by the manufacturers’ logo and a symbol of series, or color marked (medium series – blue, heavy series – red). Bundles are marked by a label with prescribed data.
Protection of the tubes surface for threading
Tubes are supplied without a temporary protection against corrosion. Upon request it is possible to deliver tubes with agreed upon anticorrosion protection.
Testing of the tubes for threadingTubes are tested with nonspecified test. Tests: leak tightness (pressure 50 bar for 5 seconds or according to EN 10246 – 1), visual inspection, tensile test, bend test and flattening test.
Certified test reportsEN 10204 – 2.1, 2.2
DIN 50049 – 2.1, 2.2
STN, ČSN 42 0250