Division of Labor Among Components in the Production Process of the Japanese 25 Used Tube Mill

The Japanese 25 used tube mill operates as an integrated and sequential production system, where each specialized component performs a distinct and critical function in transforming narrow steel strip into precise small-diameter welded tubes. Understanding the specific role of each section is essential for efficient operation and maintenance of this used equipment, which is designed for high-precision applications such as furniture, automotive parts, and light structural components, producing round tubes (Φ9.53–25mm), square tubes (13x13–20x14mm), and irregular profiles.

1. Material Handling and Feed Preparation Section:
This initial stage is responsible for the controlled and continuous supply of raw material. The system begins with the head uncoiler, which holds the coil of steel strip and pays it off in a controlled manner. Its primary function is to feed the strip into the line. The subsequent accumulator (or loop) acts as a vital buffer. It stores a certain length of strip, mechanically decoupling the uncoiling process from the constant-pull of the forming section. This allows the uncoiler to stop for coil threading or changes without interrupting the continuous operation of the main mill, which draws strip from the accumulated reserve. This separation is fundamental for achieving non-stop production runs and maintaining consistent line tension.

2. Primary Forming and Welding Core Section:
This is the transformative heart of the used tube mill. The forming machine, with its specific configuration of 8 horizontal and 7 vertical roll stands, executes the precise, multi-stage shaping of the flat strip. Each stand progressively bends the strip, gradually forming it into a cylindrical shape with its edges brought together perfectly. A dedicated press roller (1 set) then applies final pressure to align the edges immediately before welding, ensuring optimal seam preparation. Following this, the solid-state high-frequency (HF) welder performs the crucial metallurgical joining. It applies intense, localized heat via high-frequency current to the prepared seam edges, fusing them together under pressure to create a strong, continuous longitudinal weld. The stability and precision of this component are critical for the integrity of the thin-walled tubes (0.3-1.2mm).

3. Sizing, Cutting, and Finishing Section:
After welding, the closed tube proceeds to the sizing machine. This unit, with 4 horizontal and 4 vertical stands (featuring 40mm and 20mm shafts, respectively), performs precision cold-forming. Its role is to calibrate the welded tube to its exact final dimensions and geometric shape (round, square, or irregular as per the specific molds listed, e.g., Φ12.7mm, 16x12mm, or flat oval 18x8mm). Following sizing, the cold saw cuts the continuous tube into precise, predetermined commercial lengths. This saw provides a clean, burr-minimized cut. Finally, the run-out table receives and conveys the finished cut tubes. It serves as a cooling and staging platform, allowing the tubes to be collected, inspected, and bundled for further processing or shipment.

In summary, this Japanese-manufactured used tube mill functions as a synchronized production cell where material logistics, precision shaping/joining, and final finishing are handled by dedicated, specialized sections. The effective coordination of the uncoiler/accumulator, the multi-stand forming press with the HF welder, and the sizing/saw/run-out system enables this compact line to efficiently produce a variety of high-precision, small-diameter tubular products.

For more information, please pay attention to the website of Jinyujie Mechanical and Electrical Used Pipe Mill Supplier：www.usedpipemill.com.