Punch forming

Material Selection

Semi-trailers

Baosteel’s QStE Series of high strength automotive frame steel development can be a replacement for its original B510L steel. By using Baosteel QStE700TM as the replacement, some semi-trailer users reduce the thickness of upper and lower wing spars of their semi-trailers from 12mm to 8mm and the thickness of auxiliary frames from 8mm to 6mm.

Baosteel’s B600W, with good strength and corrosion resistance, is particularly suitable for the floor of the carriage. The replacement of the 2.5mm Q235 product with the 1.5mm steel can significantly reduce the weight of a semi-trailer.

Highway dump trucks

With the use of the high strength steel BC 850 develop by Baosteel, the weight of the carriage is 5.150 tons, which is 1.245 tons lighter than that of an equivalent model available (bottom: 6mm; side: 4mm) in the market；

Item
Ordinary dump truck configuration（Q235） Light-weight dump truck configuration（BC850）
Floor 6mm 4mm
Subframe 6mm 4mm
Dump board 4mm 3mm
Rear door 4mm 3mm

 

Concrete mixer truck

BW300TP is a new wear-resistant steel product specially designed by Baosteel for concrete mixer trucks. This kind of steel has good wear resistance. Through the abrasive wear test with a mix of mud and sand, it has been proven that its wear resistance is twice better than that of the conventional material 520JJ. Besides, it also has good formability and yield strength at only around 700Mpa. Nowadays, mixer truck manufacturers can directly use the new wear-resistant steel without the need to change their own equipment. The use of this material can significantly reduce the weight of the body of a mixer truck and enhance its service life, so it is popular with the users in the downstream industry.

Grade C Si Mn P S Alt Cey typical value
B300TP ≤0.35 ≤2.0 ≤2.0 ≤0.025 ≤0.010 ≥0.015 0.55
Grade Thickness mm Transverse tensile test Transverse cold bending test Surface hardness
Yield strengthRp0.2, MPa Tensile strengthRm, MPa ElongationA05，% Bend 90° Brinell hardness HBW
B300TP 3-10 ≥600 ≥900 ≥8 D=8a 250-300
Typical value 700 1000 10 D=8a Qualified 300

The wear resistance of BW300TP is twice as much as that of Q345B and B520JJ.

 

Buses

With the growing concern for buses, the all-bearing body structure is applied more and more. The conventional all-bearing body structure is manufactured using square tubes Q345, and the thickness is around 3mm. The 1.5mm Baosteel QStE700TM is now widely applied to all-bearing body structures, and the square tubes further machined by the downstream manufacturers have good precision and strength, which makes them particularly suitable for bus manufacturers. Besides, Baosteel has the ability to machine deformed steel to significantly simplify the machining process and weight of window frames. By use of Baosteel’s high strength steel, the weight of the all-bearing body structure can be reduced from 6 tons to be within 4 tons.

Mining dump trucks

Conventionally Q345 is used to manufacture the carriage of a mining dump truck, so the used thickness is big, with the floor at up to 20mm and the side plate up to 16mm. At present, the industry is more and more interested in using wear-resistance steel to reduce the thickness. Baosteel is one of the first to start manufacturing thin wear-resistant steel in China. So far, Baosteel’s new heat treatment line has been put into production, and the wear-resistant steel products will have better hardness and plates. Besides, Baosteel also proactively interact with mining dump truck manufacturers and use the new materials to help them develop new truck models in the form of EVI. Through trial use of new models at mines, it proves that the material has good sinking and wear resistance. After one month of trial use, the wear rate of the truck hopper is only one tenth of a Q345 truck hopper.

Grade Thickness mm Tensile test (transverse) Brinell hardness Impact test 90° bend test
Yield strengthReH, MPa Tensile strengthRm, MPa ElongationA50mm，% HBW Impact value（-20°C）KV2，J Bend diameter
BW300 3-10 ≥850 ≥1000 ≥10 300±30 ≥24 d=5a
BW350 3-10 ≥900 ≥1100 ≥10 350±30 ≥24 d=6a
BW400 3-10 ≥960 ≥1200 ≥8 400±30 ≥24 d=6a
BW450 3-10 ≥1100 ≥1250 ≥7 450±30 ≥24 d=8a

 

Semitrailer tractor

The QStE Series of high strength steel is featured by good formability. It can be machined into the desired automotive frame shaped through the bending process. Its high strength can help significantly reduce the thickness of the automotive frame and change the original double-beam structure into a single-beam structure.