Carbon Steel DIN 2391 Seamless Precision Pipe Used in Hydraulic

DIN 2391 requires cold-drawn seamless precision steel pipes to have the following characteristics:
The dimensional accuracy of the height: the outer diameter, inner diameter and wall thickness of the pipe have strict tolerance requirements to ensure the accurate size of the pipe.
Smooth surface quality: The inner and outer surfaces of the pipe should be smooth, without bumps, scratches, oxidation layers and other defects to ensure good sealing and fluid transfer.
Excellent mechanical properties: the mechanical properties of the pipe, such as tensile strength, yield strength, elongation and impact toughness, should meet the specified requirements.
Applicable processing performance: The pipe should have good cold processing performance, easy to bend, expand, cold forming and other processing technology.
DIN 2391 covers the requirements for materials, dimensions, tolerances, mechanical properties, surface quality and test methods of steel pipes. It is widely used in automotive manufacturing, mechanical engineering, instrumentation and hydraulic systems to meet the needs from high-precision manufacturing to high-performance work.

Product Features:
Corrosion resistant
Accurate dimensions
Can sustain high pressure & temperature load
Rust proof finish
Smooth transition from flange thickness to pipe
Ensure excellent stress distribution

Standard Specification:

The main products of steel / steel grade: DIN2391-1(ST35, ST45, ST52).

Description Name

DIN 2391 Seamless cold drawn tubes, DIN 2391 Seamless precision steel tubes, ST35 Precision tubes, ST45 Precision tubes, ST52 Precision tubes, Seamless precision tubes, DIN 2391 ST35 Seamless precision steel tubes, DIN 2391 ST45 Seamless precision steel tubes, DIN 2391 ST52 Seamless precision steel tubes, ST 52 Honed tubes, ST52 cylinder tubes

DIN2391 Application

Steel pipe for hydraulic system, steel pipe for automobile, widely used in hydraulic system steel pipe, steel pipe for injection molding machine, steel pipe for hydraulic machine, marine steel pipe, EVA foam oil pressure machinery, precision oil pressure cutting machine steel pipe, shoe machinery, hydraulic equipment, high pressure oil pipe, hydraulic oil pipe, tube joints, steel pipe joints, rubber machinery, forging machinery, die-casting machinery, engineering machinery, high pressure steel pipe for mixer pump truck, sanitation car, automotive industry, shipbuilding industry, metal processing, military industry, diesel engine, internal combustion engine, air compressor, construction machinery, agriculture and forestry machinery, etc.

 Finishing rolling process: 

Finishing rolling is a process to obtain higher precision and better surface quality by rolling the heat-treated seamless steel pipe multiple times. The specific steps include: heat treatment - pickling - cooling - finishing rolling - sizing - cutting - length - inspection - packaging. Finishing rolling can improve the precision, surface quality and mechanical properties of steel pipe.

Cold drawing process: 

Cold drawing is a process of drawing the heat-treated seamless steel pipe one by one in a cold state to obtain high precision, high surface quality and high mechanical properties. The specific steps include: heat treatment - pickling - cooling - cold drawing - deoxygenation - wet pickling - cold water washing - leveling - straightening - pickling - cold water washing - oxide skin - cold drawing - sizing - straightening - pickling - cold water washing - deoxygenation - polishing - inspection - packaging. Cold drawing can significantly improve the dimensional accuracy, surface quality and mechanical properties of steel pipes.

Hot rolling production process: 

Hot rolling is the process of heating the blank to a certain temperature, and then forming it into seamless steel pipe through multiple rolls. The specific steps include: heating - rolling - roll probe - sizing - cooling - trimming - rod breaking - inspection - packaging. Hot rolling can produce seamless steel pipes with large diameters and wall thickness, but the accuracy and surface quality are not as good as fine rolling and cold drawing.

These three processes have different applications in the production of seamless precision steel pipes, and the specific choice depends on the required dimensional accuracy, surface quality and mechanical properties.