I. Application Fields & Adopted Standards

Manufactured to DIN934 German standard and GB/T6170 Chinese national standard, these nuts are available in two high-strength grades: Grade 8 and Grade 10.

They are suitable for heavy-load assembly scenarios including construction machinery, steel structures, mining equipment, wind power facilities, bridge & road infrastructure, automobile chassis and more.

Our products are exported year-round to overseas markets such as the Middle East, Southeast Asia, Europe and America, meeting bulk procurement demands of foreign trade wholesalers and engineering purchasers.

II. Raw Materials & Production Processes

Premium steel sourced from large steel mills is adopted as raw material. The nuts undergo overall quenching and tempering heat treatment, delivering far superior hardness and tensile strength compared to ordinary Grade 4 carbon steel nuts, and resisting cracking under heavy tightening loads.

Internal threads are processed via precision tapping with neat and smooth thread profiles, creating tight engagement with high-strength bolts of matching sizes to eliminate thread stripping and locking failure during installation.

The high-temperature black oxide surface treatment forms a dense protective layer without coating peeling. It features oil resistance and high-temperature tolerance, ideal for enclosed indoor equipment assembly environments.

Besides standard heavy nuts, thin nuts and flange nuts are also in stock to fit various installation space constraints.

III. Quality Control & Delivery Capacity

All sizes M6–M48 are permanently stocked with sufficient inventory turnover. Fast production and delivery are available for small sample orders and full-container bulk orders.

Three layers of sampling inspection are conducted before shipment: hardness testing, thread go/no-go gauge inspection and dimensional verification. Relevant quality inspection documents can be provided for each batch to satisfy overseas customs clearance and project acceptance standards, with stable and controllable delivery lead times.

IV. Matching & Customization Services

Complete kits consisting of bolts, flat washers and spring washers can be bundled for one-stop fastener supply, saving customers the trouble of sourcing accessories from multiple suppliers.

Custom non-standard products can be produced against customer drawings or samples. Dimensions, strength grades and surface treatments can be adjusted on demand to meet personalized fastening requirements of special machinery and special engineering projects.

Supported by large-scale production capacity of our own factory, Wotu delivers consistent long-term supply, making us the preferred supplier for overseas hardware trade and construction projects.