Black-Plated Hexagonal Weld Nuts

• Customization: Available
• Material: Carbon Steel
• Type: Hexagon Head
• Model NO.: GB/T 13681-1992
• Connection: Common Bolt
• Head Style: Hexagonal
• Standard: DIN, GB
• Grade: 8.8
• Transport Package: Bag
• Specification: M4-M16
• Trademark: LING KE
• Origin: Yong Nian
• HS Code: 731816
• Production Capacity: 300000/Year
• Package Size: 50.00cm * 30.00cm * 30.00cm
• Package Gross Weight: 50.000kg

Product Description

Blackened hexagonal weld nuts are specialized fasteners designed for permanent, high-strength connections in metal structures. Combining the practicality of hexagonal geometry, the durability of welding, and the protective benefits of blackening treatment, these nuts serve critical roles in industries requiring reliable and corrosion-resistant joints.

Structural Design & Key Features

Manufacturing & Surface Treatment

Applications

Hexagonal Shape: The hexagonal body allows for easy gripping and torque application using standard wrenches or sockets, simplifying installation and ensuring precise tightening during assembly.
Weld Projections: Most hexagonal weld nuts feature small weld projections (nubs or studs) on their base. These projections concentrate heat during welding, creating a strong fusion bond between the nut and the base material (e.g., steel plates or components) without excessive heat damage to surrounding areas.
Threaded Bore: A precision-machined internal thread (ranging from metric sizes like M4 to M20 or imperial equivalents) accommodates bolts or studs, forming a secure mechanical connection after welding.
Blackened Surface: The blackening treatment—typically a chemical oxidation process (bluing) or black zinc plating—forms a protective oxide layer on the nut's surface. This layer enhances corrosion resistance, reduces light reflection, and provides a uniform black finish for aesthetic or functional purposes (e.g., hiding surface imperfections).

Base Material: These nuts are commonly made from low-carbon steel (e.g., Q235 or SAE 1010) for optimal weldability, as higher-carbon steels may become brittle during welding. For demanding applications, alloy steels with improved strength may be used, followed by heat treatment to enhance mechanical properties
Welding Preparation: The nuts are precision-formed via cold forging or machining, with weld projections added to their base. These projections ensure localized heat concentration during resistance welding (e.g., spot welding or projection welding), creating a strong, leakproof bond.
Blackening Process: After welding readiness, the nuts undergo blackening. Chemical blackening involves immersing the nuts in a hot alkaline solution (containing sodium hydroxide and oxidizing agents), which reacts with the steel surface to form a black iron oxide film. Alternatively, black zinc plating deposits a zinc layer via electroplating, followed by a black chromate passivation to achieve the dark finish. Both methods improve corrosion resistance and provide a decorative, low-reflectivity surface.

Automotive Manufacturing: Securing components like chassis brackets, frame rails, and engine mounts, where vibration resistance and durability are critical.
Metal Fabrication: Joining steel structures in machinery, enclosures, and industrial equipment, such as conveyor frames or storage racks
Construction & Infrastructure: Fastening metal parts in bridges, railings, and building frameworks, where outdoor exposure demands corrosion resistance.
Appliance Production: Assembling metal casings for appliances (e.g., washing machines, refrigerators) and HVAC systems, ensuring stable internal component mounting.

Packing & Delivery

Bag Packaging

Carton Packaging

Fasteners can be packaged in durable plastic bags, which are available in various sizes to accommodate different quantities (e.g., small batches of screws, nuts, or bolts). The bags are typically sealed by heat or with a zipper to prevent moisture, dust, and loss of contents. This method is lightweight, cost-effective, and suitable for retail sales, small shipments, or situations where easy access to the fasteners is needed. Additionally, clear plastic bags allow for quick visual identification of the products inside.

For larger quantities or bulk transportation, cartons are commonly used. These are sturdy cardboard boxes, often reinforced with corrugated layers to provide protection against impact during handling and shipping. Fasteners in cartons are usually pre-packed in bags or separated by dividers to avoid friction and damage. Cartons can be labeled with product details (e.g., type, size, quantity) and are stackable, optimizing storage and logistics efficiency. This method is ideal for industrial orders, wholesale distribution, or long-distance transportation where durability is a priority.

Company Profile

Company Name

 Hebei LING KE Metal Products Manufacturing Co.has firmly established itself as a leading force in the fastener industry, with a rich history and a commitment to excellence that spans over 10 years. Since its inception, the company has been dedicated to providing high-quality fasteners and comprehensive fastening solutions to a diverse range of industries worldwide.In recent decades, Hebei LING KE Metal Products Manufacturing Co. has expanded its footprint globally, establishing strategic partnerships and distribution centers in key regions around the world. This has allowed the company to better serve its international customer base and meet the growing demand for its products in emerging markets.