Pouring Reel Technology

The quality of finished rod or bar-in-coil is one of the most important aspects of overall product quality for long rolling mills. Forming a desirable coil in a bar-in-coil line begins with the design and control of the equipment in which the coil is formed: the pouring reel. Primetals Technologies has developed advanced pouring reel technology to address the current technology's noticeable limitations.

In bar mills, bar-in-coil formation involves pushing the bar into the rotating pouring reel down to the coil plate with the coil forming above the coil plate. Pushing the bar to the bottom of the pouring reel can result in poor head formation of the coil and limit rolling speed as friction and centripetal forces hinder the bar's path to the coil plate. Surface defects and what is commonly referred to as a "scorpion tail" are also possible.

To address these issues, Primetals Technologies introduced a solution in the form of a pouring reel that allows a flexible coil formation process utilizing two distinct process modes: "top-down" and "bottom-up", depending on product size, speed, and material grade.

Top-Down Mode

Top-down pouring reels favor the production of larger bar products at lower temperatures, as well as materials like stainless steel, where surface defects must be eliminated. The top-down mode situates the coil plate towards the top of the reel, while the rollerized guide leads the bar to the coil plate that descends at a controlled rate. The rollerized guide remains in a fixed position throughout the coil formation.

The fixed guide's exit location, along with its proximity to the pinch roll, allows precise control of the bar during the wobble cycle as the coil is formed. Unlike traditional systems, the fixed distance between these key components remains constant, enhancing the effectiveness of the wobble. This mode provides a denser coil formation by 3-5% compared to the bottom-up mode.

Bottom-Up Mode

Bottom-up pouring reels are more suited for producing faster rolled sections where surface quality is not a priority. In this mode, the coil plate is at the bottom of the reel, and a rollerized guide terminates close to the coil plate. The rollerized guide translates upward away from the coil at a defined rate by the system's control.

The controlled distance between the coil plate and the guide's exit improves wobble control and coil formation within the reel. This also improves tail-end formation within the reel. A reduced turndown angle to 30° from a typical 60° further aids in the coil's tail-end formation.

Benefits of the Pouring Reel Technology

• Reduces cycle time, increasing production rates and reducing coil transport times to downstream processing
• Decreases surface defect occurrence and depth
• Reduces occurrence of "scorpion tail" without the need for added process or equipment downstream
• Consistent coil density improves coil formation, enhancing cooling or fast quenching
• The reduction of coil height increases package density and improves processing/handling