Carbon cold rolled and hot rolled wire rod
Low-carbon SWRCH6 to 16A series steels are non-heat-treated materials suitable for cold heading and cold extrusion. These steels are commonly used in the production of fasteners with lower strength requirements. Due to the high degree of cold deformation and complex shapes, these materials require excellent pickling and phosphating quality. When the cold heading deformation exceeds one-third, annealing is necessary for certain steel grades. It's recommended that customers choose low-carbon grades such as SWRCH6A, especially when manufacturing fasteners with significant cold heading deformation. In terms of wire material specifications, it's advised to select similar sizes to meet product dimensions, reducing drawing deformation and minimizing work hardening effects.Free return cold rolled steel and hot rolled wire rod
In 2004, Maanshan Iron & Steel Co., Ltd. participated in the National 863 Program titled “Research on High Performance and Low Cost Cold Rolled Steel†(2003AA331030), aiming to develop independent technology for online softening and cost-effective cold heading steel wire in China.High-strength fasteners of class 8.8 and above are typically made from medium carbon or medium carbon alloy steels. The standard production process includes hot rolling, spheroidizing annealing, cold drawing, cold forming, rolling, quenching, and tempering. Spheroidizing annealing is essential to ensure sufficient plasticity for cold heading. During cold heading, the material may undergo up to 70-80% total deformation, requiring the raw material to have a low hardness level, usually not exceeding HRB82. Currently, spheroidizing annealing is the most time-consuming and energy-intensive step in fastener production, often taking 12-24 hours in batch or continuous furnaces. Hence, the industry seeks to simplify or eliminate this step.
Ma Steel’s high-line technology focuses on the latest developments in wire rod rolling, creating an independent production line with proprietary technology. They have developed annealed SWRCH35K-M and CH35A-M hot-rolled wire rods, as well as SWRCH35K-MT and CH35A-MT for export to the US market. These products are available in various diameters and are suitable for manufacturing hex bolts and similar fasteners. For fasteners with large deformation, spheroidizing annealing is still required. For nuts, MFM-1 and MFM-3 hot-rolled wire rods have been successfully developed for high-strength nuts, while MFM-2 eliminates both annealing and quenching/tempering, directly producing grade 8 nuts.
Non-regulated cold rolled steel and hot rolled wire rod
Non-tempered cold heading steel is primarily used for high-strength fasteners like 8.8, 9.8, and 10.9 bolts. Using non-tempered cold-rolled steel simplifies the production process by eliminating pre-drawing annealing and post-bolting quenching/tempering. This reduces energy consumption, shortens the production cycle, and avoids issues like surface oxidation and decarburization. Japan has already implemented industrial-scale production of this type of steel.In 2005, Maanshan Iron & Steel Co., Ltd. participated in the National 863 Program Guided Project “Research and Development of Non-tempered Steel Wire for Low Temperature Controlled Rolling and Controlled Cooling Fasteners†(2005AA001110).
In 2008, the company also undertook the National Support Program Project “Development of Low-Cost, High-Strength Non-Quenched and Tempered Cold-Rolled Steel Products for Steel Structure Joints†(2007BAE30B04).
The non-tempered steel series developed by Maanshan Iron & Steel Co., Ltd. uses micro-alloying, controlled rolling, and cooling techniques to achieve ultra-fine grain structures. By omitting the annealing of raw materials and the finishing process, the product performance meets current mechanical standards (GB/T 3098.22-2009). This new production route for high-strength fasteners (8.8–10.9) saves energy, reduces costs, minimizes environmental impact, and prevents defects such as quenching cracks and surface decarburization.
Alloy cold heading steel
Steels such as 10B21, ML40Cr, and SCM435 are mainly used for high-grade fasteners of grades 8.8 to 12.9. With strict process control, these materials offer superior performance and excellent cost-effectiveness.The shower niche is a recessed space in the bathroom for storing and placing items, like soap, shampoo and toiletries. It has a good performance of expansion function. Our shower niche are made of high-quality stainless steel, which is long lasting and requires less money on tile work.Â
Shower Niche insert,Shower Niche Stainless Steel,Recessed Wall Niche,Custom Stainless Steel Niche,Wall Recessed Shower Niche,Shower Niche Shelf, Stainless Shower Niche,Stainless Steel Niche, Shower Wall Niche,No-tile Needed Shower Shelf
Jiangmen MEIAO Kitchen And Bathroom Co., Ltd. , https://www.meiaosink.com