PROCESS FOR MANUFACTURING STEEL CHEESE TUBES/JUMBO TUBES/PIPES FOR WOVEN-SACKS AND COPS/BOBBINS/PIRNS FOR SYNTHETIC YARN

摘要

The present invention relates to a process for manufacturing steel Cheese Tubes/Jumbo Tubes/Pipes for woven‐sacks and Cops/Bobbins/Pirns for synthetic yarn. In process of present invention, strip of basic steel grade (SAE 1020, SAE 1026, ST 52, ST 52.3, SAE 1541 and MC 11 and similar or equivalent grades.) is selected as feed stock. The strip undergoes forming process to form steel Tube/Pipe and faying edges of said steel Tube/Pipe are welded through electrical resistance welding (ERW). Thereafter, ERW tube/Pipe is straightened on hyperbolic Tube/Pipe straightening machine. The straightened Tube/Pipe is hardened by induction hardening at 900 °C‐950 °C to achieve enhanced tensile strength and improved elongation to withstand the pressure exerted on steel Cheese Tubes/Jumbo Tubes/Pipes during winding of flat tape yarn for woven sacks and Cops/Bobbins/Pirns during winding of Nylon (Polyamide) and Polyester synthetic yarn. Thereafter, the Tube/Pipe is optionally subjected to coating particularly for cheese tube/pipe and jumbo tube/pipe.