The production process of KPO fastener systems directly affects their quality and performance. The core production process is as follows:
Raw material preparation: Mostly high-quality steel and alloy steel are used, requiring high strength, good toughness and corrosion resistance. Before entering the factory, they must undergo strict testing such as chemical composition analysis and mechanical property testing to ensure that they meet the standards.
Forming process: Cold heading is commonly used for conventional parts such as bolts and nuts. Plastic deformation at room temperature can improve material utilization and retain good mechanical properties; hot forging is suitable for parts with complex shapes and high strength requirements. The material structure is improved by heating forging, but the energy consumption is high.
Thread processing: Thread rolling and thread rolling are common methods. Thread rolling uses a thread rolling wheel to extrude threads, with high precision and good surface quality, and is suitable for mass production of standard parts; thread rolling is extruded by two thread rolling plates, with high efficiency, but high requirements for equipment and material plasticity.
Heat treatment: Quenching can improve hardness and strength, while tempering eliminates the internal stress generated by quenching, balances hardness and toughness, and selects different tempering temperatures according to product requirements.
| Specifications for ONE unit of KPO type rail fastening system | ||
| Item | Quantity | Material |
| KPO clip | 2 | Q235 |
| Screw spike | 2 | Grade 4.6: Q235 |
| Grade 5.6: 35# | ||
| Grade 8.8: 45# | ||
| HS bolt 4 | 4 | Grade4.6: Q235 |
| Grade5.6: 35# | ||
| Grade8.8: 45# | ||
| Hex nut 2 | Grade 5: 35# | |
| 2 | Grade 8: 45# | |
| Double coil spring washer | 2 | 65Mn |
Surface treatment: Galvanizing has low cost and can meet general outdoor corrosion protection needs; nickel plating has both beauty and corrosion resistance and is suitable for high-end scenes; protective coating can customize performance according to special environments.
Quality inspection: covers dimensional accuracy measurement, mechanical property testing (tensile, hardness, impact testing, etc.), surface quality inspection (visual, non-destructive testing) and anti-corrosion performance inspection (salt spray, wet heat testing) to ensure that the product meets the standards.