ST37.4 ST44.4 ST52.4 Priceison Steel Tube for dynamic Loads Normal Pressures 100 to 400 bar
ST37.4 ST44.4 ST52.4 Steel Grade Seamless Steel Tube for dynamic Loads Normal Pressures 100 to 400 bar is our company mainly product. It is widly used in heavy duty truck, military industry, railway locomotive,engine filed and the gas line in special vehicle.They could meet the requiremnts because of high precison of Out diameter and Inner diameter. Also its anti corrosion performance.
Standard: DIN 1630 DIN2445 OD: 4-90mm Thickness: 0.5-20mm
Grade: ST37.4 ST44.4 ST52.4
Heat Treament: NBK(+N) normalized, BK, GBK,
Surface Treament: Army green passivated, Sliver Galvanized, Black Phosphated，Black paint，
Dimension Telorance: According to DIN1630 DIN2445 Standard
High precison, smooth surface
Strong anti rust/corrosion property
No any corrosion after 220 hours’ Sale Spray Test
The tubes can be produced in the following delivery conditions:
BK (+C) Cold finished/hard (cold finished as drawn).
No heat treatment after the last cold forming process.
BKW (+LC) Cold finished/soft (lightly cold worked)
After the last heat treatment there is a light finishing pass (cold drawing).
BKS (+SR) Cold finished/stress relieve annealed.
After the final cold forming process the tubes are stress relieve annealed.
GBK (+A) Annealed.
After the final cold forming process the tubes are annealed in a controlled atmosphere.
NBK (+N) Normalized. (Mainly focus on)
After the final cold forming process the tubes are annealed above the upper transformation point in a controlled atmosphere