II. Seamless Steel Tubes     for Hydraulic Lines     acc. to DIN 2445 Hydraulic tubes acc. to DIN 2445 Part 1 (sheet 1) 1. The technical conditions of delivery     according to DIN 1629/sheet 4, apply 2. Material: St 52.4 ACC. TO din 1629/sheet 4 3. Method of production and tolerances: a) hot-rolled acc. to DIN 2448/ DIN 1629/ sheet 4 b) cold-rolled acc. to DIN 2391/C technical conditions of delivery to DIN 1629/ sheet 4 tolerances to DIN 2391 4. Field of application: nominal pressures 100 to 400 bar applicable pressures 160 to 500 bar Hydraulic Tubes acc. to DIN 2445 Part 2 (sheet 2) 1. The technical conditions of delivery     according to DIN 2391 part 2, quality     grade C, apply 2. Material: St 35.4 acc. to DIN 1629/sheet 4 3. Delivery condition: NBK 4. Method of production: seamless cold drawn 5. Tolerances: DIN 2391/ sheet 1 6. Pressure test: 50 bar KWPD (cold water) or eddy-current tested to SEP 1925 or acc. to customer's requirements 7. Field of application: Nominal pressures 64-400 bar applicable pressures 125 to 500 bar of DIN 2445/ sheet 2. 8. Marking: All tubes of this standard are to be marked over the whole length with trade mark and steel grade i.e. St 35.4 (only tubes with an outside diameter exceeding 10 mm) Surface treatment: On requirement tubes acc. to DIN 2445/ sheet 2m with and inside dia. exceeding 6 mm can be phosphated. In this case they are stencilled on the phosphated surface