DIN557 DIN562 Square Nuts

The DIN557 and DIN562 square nuts from Handan Daoning Fasteners Co., Ltd. are precision-forged fasteners designed for high-torque structural applications. They conform to DIN 557 for metric sizes and DIN 562 for imperial sizes, with dimensions ranging from M6 to M42 and 1/4 inch to 1-1/2 inch. These nuts feature a square profile with chamfered edges to aid alignment and reduce stress concentration during installation.

Materials include carbon steel, alloy steel, stainless steel, and brass, with mechanical grades such as SAE J995 Grade 2, ASTM A563 Grade A, and Class 4 to 8. Surface finishes include plain, zinc plated in clear, blue, yellow, or black, black oxide, nickel, chrome, and hot-dip galvanized. Typical tensile strengths range from 400 MPa for plain carbon steel to over 1000 MPa for alloy steel Class 8. The nuts are manufactured using cold heading and thread rolling processes to ensure consistent dimensional accuracy.

These square nuts are used in structural steel assemblies, wind turbine towers, oil and gas pipelines, and heavy machinery where vibration resistance and torque retention are critical. Buyers include industrial equipment manufacturers, construction contractors, and engineering firms in North America, Europe, and Southeast Asia. Packaging is in 25 kg cartons on wooden pallets, with custom options available. Minimum order is 500 kg per size and specification. Trade terms include FOB, CIF, CFR, EXW, DDU, and DDP.

Handan Daoning Fasteners Co., Ltd. is based in Handan, Hebei Province, China, with a registered address in Congtai District. The company is verified at harbor trust level, indicating compliance with export documentation and shipping protocols. The listing confirms the presence of calipers, go/no-go gauges, tensile testers, hardness testers, salt spray testers, and hot-dip galvanizing thickness testers, suggesting in-house quality control capability.

The supplier does not disclose workforce size, annual production volume, or client names. There is no mention of ISO certification, quality management systems, or third-party audit reports. While the listing states supply of material and test reports, no specific standards or test methods are cited. Buyers should request batch-specific test certificates for mechanical properties and coating thickness before placing orders.