Hot Work Steel Mandrel Bar For Seamless Tubes
Core component for seamless tubes: Mandrel bars
We deliver mandrel bars of up to 28 m in length and up to 365 mm in diameter to nearly all manufacturers of seamless tubes. A mandrel bar is used to roll a pre-pierced steel billet to produce a tube blank (the preliminary seamless tube).
We produce these mandrel bars in-house on one of the largest forging machines as well as on a state-of-the-art rolling mill, including straightening and machining units specifically designed for the mandrel bar long product.
We can supply you with mandrel bars made from general-purpose hot work steels and specialty steels tailored to suit the various tube rolling methods and made to withstand individual stresses in the following versions, all in based on your request:
Finish-machined and chrome-plated
Finish-machined and oxidized
Pre-machined, i.e. quenched and tempered, peeled
Smelting method
EAF+LF+VD OR +ESR
Delivery status and processing purposes.
Tempered after turning or grinding, delivered in black state.
Processing use: cutting.
Forging ratio or rolling ratio ≥ 8 / 1.
Delivery hardness delivery hardness 320-370HB in tempered condition.
Grade and chemical composition
Grade | C | Si | Mn | Cr | Mo | V | P+S | S |
1.2344/H13 | 0.32-0.38 | 0.70-1.20 | 0.30-0.60 | 4.50-5.50 | 1.00-1.50 | 0.80-1.20 | ≤0.020 | ≤0.008 |
Mechanical Properties
Hardness HB | Yield | Tensile | Elongation | Reduction | Impact KV2 |
(N/mm2) | (N/mm2) | (%) | (%) | (J) | |
320-370 | ≥931 | 1127-1274 | ≥8 | ≥25 | ≥15
≥20 |