Carbon Steel 7/16 Safety Belt Nut, 4 Hole Square Flange Internal Thread Mounting Nut For Automobile Safety Belt-Zhejiangxinye Automobile Technology Co. , Ltd.

Core Features

7/16-20UNF Thread Specification – The internal thread conforms to the unified fine (UNF) thread standard, which has been standardized for safety belt mounting applications in automotive manufacturing since the 1960s. The 7/16-20UNF thread is specified by industry standard QC/T 712 for seat belt device fixed connections.

Square Flange Configuration – The flange is formed with a square or rectangular profile that provides a stable mounting surface. The flat flange design provides a bearing surface that distributes clamping loads across the workpiece and resists rotation during bolt tightening.

Four-Hole Mounting Interface – Four mounting holes are positioned on the flange, enabling secure attachment to the vehicle body or seat structure through welding or mechanical fastening. The multiple-hole configuration provides load distribution and mounting stability.

Safety Belt Anchor Application – Designed specifically for safety belt anchorage points in vehicle body pillars and seat structures. The anchor nut plate withstands shock loads applied from the safety belt to the pillar structure under crash or accident conditions.

Product Characteristics

The nut is manufactured in accordance with QC/T 712-2011, the Chinese automotive industry standard for safety belt welding nuts. The standard specifies the dimensions, technical conditions, and material requirements for both hexagon and square welding nuts used in safety belt device fixed connections. The 7/16-20UNF-2B thread specification is the designated thread size for automotive body and seat safety belt device fixed connections.

The square flange provides a stable mounting base that resists rotation during installation. The four holes on the flange enable secure attachment to the body panel or seat structure, either through welding or through-hole fastening. The flange design provides a load-bearing surface that distributes clamping loads across the workpiece.

Material composition is controlled to meet specified strength requirements. Carbon steel grades are used for general applications, with heat treatment processes applied to achieve defined hardness and strength characteristics. Surface treatment options include zinc plating, phosphate coating, and other finishes based on corrosion resistance requirements.

Application Scenarios

Vehicle Body Pillar Mounting – Used in automobile body pillar structures where the anchor nut plate is disposed in the space between inner and outer panels to create attachment points for safety belt fittings. The nut plate is secured by welding to the body structure to withstand shock loads from safety belt during collisions.

Seat Structure Attachment – Applied in vehicle seat frames and assemblies where safety belt receptacles or buckles require secure mounting points. The four-hole flange provides a stable mounting interface for seat belt retractor assemblies.

Welded Installation – Designed for welding directly onto vehicle body panels or seat structures. The welding configuration provides permanent attachment that meets the safety requirements for safety belt fastening hardware. The square flange design with four holes allows for welding at multiple points.

OEM Replacement – Used as genuine replacement parts for safety belt anchor nuts in vehicle service and repair applications. The nut is compatible with various vehicle models as an OEM replacement component.

Customization Options

Specifications and configurations can be adjusted based on application requirements. Material grades include carbon steel for general applications and other steel grades for enhanced strength requirements. Surface treatments are selectable according to environmental exposure conditions, including zinc plating, phosphate coating, and other finishes for corrosion resistance. Thread specifications can be matched to application requirements, with metric or unified thread options available.

Frequently Asked Questions

Q: Why is the 7/16-20UNF thread used for safety belt nuts?
A: The 7/16-20UNF thread is a unified fine (UNF) thread specification that has been standardized for safety belt mounting hardware in the automotive industry since the 1960s. The standard is defined in QC/T 712 for automotive safety belt device fixed connections.

Q: What welding methods are compatible with these nuts?
A: The nuts are designed for welding attachment to vehicle body structures. Resistance welding or projection welding are typically used, with the nut placed on the workpiece and welded at the designated contact points. The welding configuration provides permanent attachment that meets safety requirements.

Q: What is the purpose of the four holes in the flange?
A: The four holes enable secure attachment through welding or mechanical fastening. The multiple holes provide load distribution across the mounting surface and prevent rotation during bolt tightening.

Q: Are these nuts reusable after welding?
A: The welding-type configuration is intended for permanent installation. Once welded, removal requires destructive methods. For service applications, the replacement nut must be installed according to the vehicle service procedure.

Q: What is the applicable standard for safety belt welding nuts?
A: QC/T 712-2011 is the Chinese automotive industry standard for safety belt welding nuts. It specifies the dimensions, technical conditions, and material requirements for 7/16-20UNF welding nuts used in automotive safety belt device fixed connections.

Installation Considerations

The nut should be positioned with the flange seated against the workpiece surface. For welding installation, the nut should be placed at the designated mounting point and welded using appropriate welding equipment. The welding parameters should be set based on the material thickness and grade specification. The square flange provides resistance to rotation during bolt tightening. Thread condition should be inspected before installation; damaged threads may affect assembly integrity. For plated nuts, coating thickness should be within specified tolerances to maintain thread fit. The anchor plate is typically installed in body pillars where it can withstand shock loads from safety belts under crash conditions.

Q: What information do I need to provide to get an accurate quotation?

You need provide the model, specification, quantity, technical specifications and other special requirements of the cable products

Q: What is the monthly supply capacity?

The average monthly output of cables is approximately 50,00 kilometers

Q: How is your after-sales service?

Our company has a professional after-sales team that covers the entire process from "before service" to "after service", and we conduct regular customer satisfaction follow-ups.

Q: How long is the product warranty time?

One year

Q: Can you do customized products?

Yes, we can produce both standardized products and customized ones. We can produce customized products according to the customer's drawings or samples.