COLD DRAWN PIPES FOR HYDRAULIC CYLINDERS FINISHED INSIDE
The characteristics and the precision of cold drawn steel tubes make these products particularly suitable for use as cylinders and pistons in hydraulic and pneumatic systems for power transmission and control systems.
The pipes are manufactured in accordance with DIN 2391 and EN 10305SUPPLY : SHINY RAW DRAWN WITH STRESS RELIEVING(SR sec . EN10305 / BK + S sec . DIN 2391 )
After cold forming , tubes of this delivery condition are subjected to heat treatment. In this way, the residual stresses are reduced to a minimum and the properties of the plastic deformation improved.
DRAWN BRIGHT RAW (C sec . EN10305 / BK sec . DIN 2391 )The tubes in this state of delivery are not subjected to heat treatment after cold forming . The properties of the plastic deformation of the steel are limited and you have to predict residual stresses.Normalized (N sec . EN10305 / NBK sec . DIN 2391 )After the cold forming , these tubes are subjected to thermal treatment under protective gas at a temperature above the upper critical point .
SIZE AND TOLERANCE :
See table .
Commercial 6 to 8 meters.Fixed by cutting machine ( standard tolerance -0 / +3 when not specified in the order)
INSIDE DIAMETER : ISO H8ROUGHNESS ' INTERNAL : max 0.4 microns Ra .
According to EN10305 and DIN 2391 standards .
STRAIGHTNESS ' : 0.0015 to Rp 0.2 L ≤ 500 N/mm2 and 0.002 L for Rp 0.2 > 500 N/mm2OVALIZATION : Determined by the outside diameter tolerances .
MARKINGS : On all the tubes containing the following information: - the manufacturer's mark , steel grade standards.
CERTIFICATES : we equip the provision of related certificates of origin bearing chemical analysis and mechanical testing related to the production standards .