550mm hot rolling mill

1. Equipment Overview
This equipment is a 550mm hot rolling mill, model Y2026M07HRM24L, manufactured by Jiangsu Mingkerui Metallurgical Machinery Co., Ltd., commissioned in 2017, and taken offline in 2026. This is a complete medium-to-narrow strip hot rolling equipment package, covering the entire hot rolling process from billet roughing and finishing to coil winding. Hot rolling mills are the"leader"equipment in the metallurgical industry—they transform steel billets through heating and multiple rolling passes into hot-rolled coils, providing fundamental raw material for subsequent cold rolling, tube making, stamping, and other deep-processing operations.

2. Manufacturer Background
Jiangsu Mingkerui Metallurgical Machinery is a significant player in China's metallurgical equipment manufacturing sector, specializing in the R&D and production of hot rolling lines, cold rolling equipment, and supporting finishing equipment, with extensive engineering experience and technical strength in small-to-medium规格 hot rolling lines.

3. Raw Material Specifications

• Material: MS (Mild Steel, equivalent to Q195/Q235);

• Billet specifications: 150×150mm square billet or 130×220mm rectangular billet;

• Billet length: 6000mm;

• Maximum single weight: 1.35 tons.

The line uses continuous-cast square or rectangular billets as raw material, which are fed into the rolling mill after heating in a reheating furnace.

4. Finished Product Specifications

• Finished width: 150-240mm;

• Finished thickness: 2-5mm;

• Coil diameter: Minimum 520mm, maximum 1500mm;

• Maximum rolling speed: 10m/s (600m/min).

The finished product is hot-rolled coils, which can serve as raw material for cold rolling mills (after pickling), tube mills, or be sold directly as commercial hot-rolled coils.

5. Mill Configuration — Complete Process from Roughing to Finishing

The line is divided into three major areas: Roughing Zone (RM+E1) , Finishing Zone (F1-F6) , and Coiling Zone. Detailed parameters for each stand are as follows:

6. Roughing Zone (RM + E1)

RM (Roughing Mill) :

• Type: 3-Hi (three-high) , a classic hot roughing configuration with two large outer rolls and one smaller middle roll, enabling reversing rolling;

• Work roll diameter: Φ560/490mm (new 560mm, replaced when worn to 490mm);

• Barrel length: 1500mm, far exceeding the finished width (240mm), providing ample deformation space for larger billets;

• Motor power: AC 2500kW — the largest single motor on the entire line, providing the enormous rolling torque required during roughing;

• The roughing mill reduces 150×150mm billets through multiple reversing passes to an intermediate thickness (approximately 20-30mm) suitable for finishing.

E1 (Edger Stand) :

• Type: Vertical edging mill, used for width control and side rolling of the billet;

• Work roll diameter: Φ500/450mm;

• Barrel length: 200mm;

• Rolling force: 1000kN;

• Motor power: DC 250kW;

• The primary function of the E1 edger is width control—ensuring finished width accuracy through lateral rolling and improving strip edge quality to reduce edge cracking defects.

7. Finishing Zone (F1-F6)

The finishing zone consists of 6 continuous stands, divided into 4 x 2-Hi mills (F1-F4) + 2 x 4-Hi mills (F5-F6) . This"2-Hi + 4-Hi"combination is a typical design for small-to-medium规格 hot rolling lines:

F1-F4 (2-Hi Finishing Mills) :

• Work roll diameter: Φ460/400mm;

• Barrel length: 680mm;

• Rolling force: 6000kN each;

• Motor power: DC 1000kW each × 4 = 4000kW;

• 2-Hi mills feature simple construction and good rigidity, suitable for large-reduction intermediate passes. F1-F4 undertake the primary reduction from roughing intermediate thickness to near-final thickness.

F5-F6 (4-Hi Finishing Mills) :

• Work roll diameter: Φ320/280mm (smaller work roll diameter facilitates rolling thinner gauges);

• Backup roll diameter: Φ560/510mm (large-diameter backup rolls provide strong support to work rolls, reducing bending deflection);

• Work roll barrel length: 690mm, backup roll barrel length: 680mm;

• Rolling force: 4000kN each (slightly lower than F1-F4, as reduction decreases in later passes);

• Motor power: DC 800kW each × 2 = 1600kW;

• 4-Hi mills use small-diameter work rolls combined with large-diameter backup rolls, enabling rolling of thinner gauges with better shape control. F5-F6, as the final finishing stands, roll the strip from intermediate thickness to final thickness of 2-5mm, ensuring shape and surface quality.

8. Total Drive Power Summary

The total main motor power of the entire line reaches 8350kW. Including auxiliary equipment (roller tables, coilers, shears, hydraulic systems, etc.), the total installed power exceeds 10,000kW. This is a medium-to-narrow strip hot rolling line with ample power capacity.

9. Equipment Age Advantage
This equipment was manufactured in 2017 and taken offline in 2026, with approximately 9 years of actual service. In hot rolling lines, 9 years represents a"mid-age"equipment, far superior to common second-hand hot rolling equipment with 15-25 years of service age:

• Main structures (housings, roll bearing chocks, gearboxes, etc.) have controlled wear levels;

• Electrical systems (DC motors, thyristor rectifiers, PLC control systems, etc.) remain in good condition;

• Capable of continuing service for 10-15+ years, with a long remaining service life.

10. Product Positioning and Downstream Applications
The 150-240mm wide, 2-5mm thick hot-rolled coils produced by this line are mainly used in:

• Cold rolling raw material: Supplied to cold tandem mills after pickling (can form upstream-downstream integration with the previously described 5-stand 600mm or 6-stand 650mm cold tandem lines);

• Tube making raw material: Billet material for high-frequency welded pipes, square tubes, rectangular tubes, etc.;

• Structural applications: Raw material for cold-formed sections such as C-channel and Z-channel;

• Stamping applications: Hot-rolled stamping raw material for hardware parts, automotive components, etc.;

• Commercial hot-rolled coils: Directly sold as commercial hot-rolled coils in the market.

11. Equipment Completeness Assessment
Based on the technical data sheet, this equipment includes a complete process configuration:

• Roughing mill (RM): 3-Hi, 2500kW — providing powerful breakdown capability;

• Edger (E1): 250kW — ensuring width accuracy;

• 4 x 2-Hi finishing mills (F1-F4): 1000kW each — undertaking primary reduction;

• 2 x 4-Hi finishing mills (F5-F6): 800kW each — ensuring final gauge accuracy and shape control.

This is a fully independent hot rolling line"from billet to coil"with complete functionality, capable of completing the entire hot rolling process without reliance on external rolling capacity.

12. Integration with Cold Rolling Lines
This 550mm hot rolling line forms a perfect upstream-downstream integration with the previously described cold rolling equipment (5-stand 600mm tandem line, 6-stand 650mm tandem line):

• The hot rolling line (this equipment) rolls 150×150mm billets into 2-5mm × 150-240mm hot-rolled coils;

• After pickling, the hot-rolled coils enter the cold tandem line (5-stand 600mm or 6-stand 650mm) for further cold rolling to 0.3mm thin strip;

• The cold-rolled coils then pass through the 850mm tension leveler for shape improvement and stress elimination;

• Final products can enter slitting lines or cut-to-length lines for finished product processing.

If a buyer simultaneously acquires this hot rolling line + cold tandem line + tension leveler + slitting/cut-to-length lines, they can build a complete metal processing industry chain from billet to finished sheet/coil , achieving extremely high self-sufficiency and product added value.

13. Equipment Dimensions and Weight Estimate (Based on Industry Experience)
Based on industry standard design references for 550mm-class hot rolling lines, a reference range can be provided:

• Total equipment weight: Typically in the 500-800 ton range;

• Roughing mill RM housing + rolls: Approximately 100-150 tons;

• Finishing mills F1-F6 housings + rolls: Approximately 40-60 tons each, totaling 240-360 tons;

• E1 edger: Approximately 20-30 tons;

• Main motors (8 units) total weight: Approximately 80-120 tons;

• Auxiliary equipment (roller tables, pushers, shears, coilers, etc.): Approximately 80-150 tons.

The above are estimates; actual weights should be based on the physical equipment. Hot rolling lines are heavy metallurgical equipment with high requirements for civil foundations, building height (including overhead cranes), and utility supplies (water, power, gas). Buyers should confirm site conditions meet installation requirements prior to procurement.

14. Conclusion
In summary, this 550mm hot rolling line is a fully functional, well-configured, ample-powered (8350kW main motors), moderately-aged (2017 manufacturing) second-hand hot rolling equipment package. Its complete processing capability from 150×150mm billets to 2-5mm hot-rolled coils makes it the"leader"equipment for building an independent metal processing industry chain. For steel processing enterprises, industrial parks, or large manufacturing groups seeking to achieve"billet-to-finished"full-process self-sufficiency, this represents a strategically valuable core equipment line for procurement consideration.