CLOSED-END FLAT/ROUND HEAD BLIND RIVET — 30-CLASS STEEL

This product is a closed-end flat/round head blind rivet with a 30-class (steel) performance grade, manufactured in accordance with GB/T 12615.1 or ISO 15973. It consists of a round-head rivet body with a closed end and a steel mandrel. During installation, a rivet gun is used to operate from a single side; once the mandrel is pulled to fracture, the rivet body expands at the blind end to form a locked joint, achieving a high-strength, high-seal-performance fastening connection. The common material combination is a 10-carbon steel body (zinc-plated) and a 45-carbon steel mandrel (black oxide or phosphated).

I. Product Features

Fully Closed-End Structure: The rivet body features a fully sealed blind end (distinct from the open-end type with a through-hole), completely blocking gas and liquid leakage paths.

Flat/Round Head Design: The rivet head adopts a low-profile cylindrical flat-top shape; after installation it sits flush against the surface for a clean and aesthetically pleasing finish, with minimal protrusion above the workpiece surface, preventing snagging on cables or debris.

30-Class Carbon Steel Construction: The rivet body uses high-quality low-carbon steel with good plasticity for smooth expansion and forming; the mandrel uses medium-carbon steel, heat-treated for high strength, ensuring the locking force generated at the moment of fracture is sufficient to draw the workpiece tight.

Single-Sided High-Efficiency Installation: Only requires operating a rivet gun from one side of the workpiece to complete fastening, ideal for blind holes or internal pipe connections where the back side is inaccessible.

Anti-Corrosion Surface Treatment: The rivet body is typically zinc-plated (white zinc or colored zinc), providing good corrosion resistance.

II. Product Advantages

Complete Leak-Proof Sealing: Compared with open-end rivets, the closed-end design provides 100% waterproof, dustproof, and airtight sealing — no additional sealant application is needed.

High Strength and Shear Resistance: The 30-class carbon steel construction delivers shear strength and clamping force far exceeding those of aluminum rivets, capable of withstanding substantial structural dynamic loads.

Internally Locked Fracture: The broken mandrel fragment remains tightly locked inside the sealed rivet body after fracture — it will not fly out to cause injury and leaves no metal debris inside equipment, making it especially suitable for installation inside precision electrical equipment.

Vibration Resistance and Anti-Loosening: After expansion, the rivet body tightly fills the hole wall, forming a permanent mechanical lock with vibration resistance far superior to ordinary screws and nuts.

Consistent Installation Quality: The pulling force is preset by the tool, unaffected by individual operator strength — every rivet achieves uniform locking force, ensuring consistent quality and standardization.

III. Scope of Application

Automotive and Body Manufacturing: Automotive body panels, mirror brackets, door lock reinforcements, and bumper brackets. Especially used for waterproof and dustproof areas such as wheel well linings and water channels inside fenders.

Containers and Enclosures: Waterproof riveting of freight container walls, refrigerated truck bodies, and industrial cabinet base plates — ensuring rainwater does not seep through rivet holes.

HVAC and Air Conditioning: Connections between air ducts and flanges, air handling unit casings, and fan volute housing sealed assemblies — preventing air leakage and cold energy loss.

New Energy and Battery Packs: Sealed fastening of electric vehicle power battery PACK housings (used together with sealing gaskets), preventing moisture and vapor intrusion.

General Sheet Metal Fabrication: Any metal sheet or profile connection scenario that requires sealing performance combined with single-sided rapid automated assembly.