Steel Tube Handbook - 2018

89 Precision tubes, delivered in coils Precision steel tubes, delivered in coils, find its application in many fields of industry for example as injection tubes for diesel engines, tubes for distribution of oil or fuel. Tubes in coils are delivered in accordance with EN 10305-1 (EN 10305-2) and DIN 2391 (DIN 2393). Dimensions of tubes in coils Tubes are delivered in a range, outside diameter between 4 and 18 mm, wall thickness between 0.45 and 2.5 mm. Other dimensions may be delivered upon agreement. For application to injection equipments of combustion engines (diesel) fol- lowing dimensions of tubes may be delivered: 6x1, 8; 6x2,1; 6x2,125; 6x2,2; 6x2,25 mm. Diameter of the coil alone is between 750 and 1200 mm depending upon the outside diameter of the tubes. Depending upon the outside diameter of the tube, inside in the bundle there is a tube with a length between 60 to 560 m (max coil weight is 50 kg). The types of tubes’ steel in coils E 215, E 235, E 255, E 355, C 15, other grades upon agreement. Injection tubes are produced from the St 30Al steel a SAE 1010. Tubes in bundles – delivery condition +C (BK) Cold drawn / hard. After the last cold forming, thermally not processed. +N (NBK) Normalized. After the last cold drawing the tubes are normalized in protective atmosphere. +LC +A +SR Tolerances Tube tolerances are in accordance with EN 10305-1, see table 25 page 69. D tolerances for product range is ± 0,08 mm, d tolerances are ± 0,08 mm or ± 0,15 mm depends on D and wall thickness tolerances are ± 10 %. The reduced tolerances have to be agreed. Surface conditions Surface fulfilled requirements of EN 10305 – 1. Ra ≤ 3μm. Packaging of the tubes in coils Bundles of tubes are packaged into paper boxes weighing between 100 to 120 kilograms which are subsequently stored on wooden pallets or into metal containers weighing up to 400 kilograms. Surface protection and marking Tubes in coils are marked with labels. A label contains all information requested by the standards. The tube outside surface is oiled. The tube inside surface is oiled in delivery condition +C or +LC. There is not tube surface protection in delivery con- ditions +N, +SR and +A. Testing of the tubes in coils Tubes are tested by eddy current according to EN 10246-3. Certificates for tubes in coils Certificates are issued according to EN 10204/3.1.