I. Summary
The mill is intended for manufacturing of square pipe of 20*20mm-85*85mm with thickness of 0.8mm–4.5mm from cold-rolled and hot-rolled coil strip by means of unclosed tubular blank with its subsequent welding into tube, edge heating by means of solid state high-frequency welder, longitudinal seam welding in rolls of tube welding machine, cooling, further sizing or shaping and on-stream cutting of endless tube in measured lengths.
Finished product will be of round, square or rectangular pipe.
II. The technical flow of the production line
{SteelTape}→→ Double-head un-coiler →→Strip-head Cutter and welder→→Spiral
Accumulator→→Forming section(Flattening unit +Main driving unit +Forming unit +Guide unit +High frequency induction welding unit +squeeze roller)+ De-burr frame →→Cooling unit →→ Sizing unit and straightener →→Flying saw under→→Computer
control →→ Run-out table
III. Basic conditions:
a) Steel Pipe Specification
1. Pipe diameter: Ø25–Ø108mm
Thickness: 0.8-5.0mm
Square/rectangular pipe: 20*20m- 85*85mm
Pipe Thickness: 0.8– 4.5mm
2. Pipe Length: 6.0m – 9.0m
3. Length Tolerance: +/-3mm
b) Strip Coil Specification
1. Material: Low Carbon steel
(δb≤500Mpa, δs≤355Mpa)
2. Strip coil : Inner diameter: Φ508-610mm
Outer diameter: Φmax=1800mm
Strip steel width: 80mm-340mm
Strip steel thickness: 0.8–5.0mm
The maximum weight: 7 tons
c) Electricity
1. Dynamic power: AC380V±10%, 3phases, 50Hz±1.0%
2. Control Power: AC220V±10%, one phase, 50 Hz ±1.0%
d) Electric installed capacity: appro. 500KW
e) Cooling water
1. Reservoir for High Frequency equipment: 20 m³, one set
2. Reservoir for circulating cooling water: 15 m³, one set
f) Compressed air
1. Pressure: 0.4Mpa
2. Flow: 1.0m3/h
g) Production capacity
Annual output: 20000 ton, according to the yearly working days,daily working hours and the products.
h) Line speed: 60-90m/min
