Flat Head Closed Round Body Knurled Blind Rivet Nuts

Name: Flat Head Closed Round Body Knurled plain Blind Rivet Nuts—Closed End

Size: M3、M4、M5、M6、M8、M10、M12

Material: Carbon Steel

Surface treatment: Zinc-nickel alloy with anti-loose glue

Grip Range: 0.5-5.5mm.

Designed with a closed end and a sizeable flanged head with a cylindrical groove and O-ring seal mounted underneath, Juxin Fastener’s cold-formed Juxin fasteners blind rivet nuts in steel and stainless steel offer a worry-free, watertight fastening solution in many critical applications.

A setting tool performs an axial crimping action during rivet nut installation. The O-ring seal slides into the groove and is compressed between the flanged head and the plate or profile where the rivet nut is installed. The hex-shaped shank prevents spin out, resisting a torque-to-turn force of at least 30Nm in M8.

After setting, the unique head design ensures metal-to-metal contact on either side of the O-ring that firmly remains in the conically shaped recess, resulting in optimal seal compression. This guarantees a well-functioning seal, ideally positioned away from possible burrs or sharp hole edges and protected against UV light.

The under-head seal protects against fluids, moisture, oil, or dirt ingress, even under up to 10 bar pressure. The Juxin fasteners' design is IP 68, guaranteed under Juxin fasteners test conditions, and available in thread sizes M5 to M8. The standard O-ring seal material is NBR (Buna-N). Still, other O-ring materials (Viton, EPDM, silicone, etc.) can be offered when a specific pressure, temperature resistance, or chemical compatibility is required. 

Originally designed to prevent leaks in a boot hinge assembly in a premium car, the watertight JuXin Fasteners are a trusted solution in many other challenging applications, too. demanding applications

As application requirements became increasingly complicated, other watertight rivet nut solutions must be conceived. Therefore, Juxin Fasteners developed the flat-head blind rivet nut series, involving a non-reactive peripheral seal made of flexible, organic-based material applied to the under-head bearing surface of a flat-head Tubtara rivet nut.

The polyurethane seal compound is resistant to many automotive oils, antifreeze, and transmission fluids and has a sealing capacity exceeding 150 bar. The material offers a temperature resistance from -40 °C to 100°C for continuous usage (150°C peak temp) and is gap-filling, forming a robust seal between mating surfaces. Slight variations in seal thickness may influence head height and grip range, but a correctly installed flat head blind rivet nut ensures an IP 67 waterproof assembly.

This seal can be applied under the flat head of stocked standard parts in all materials and shank shapes, offering OEM customers very short delivery times. It is the preferred solution for numerous applications, such as roof rack assemblies, battery packs, or enclosure covers.

New Juxin fastener developments focus on their outstanding sealing properties rather than on fastening. The latest designs feature options like male or female threads or hose connections, offering zero-risk assembly solutions in HVAC and fluid control applications.

The thread area is enclosed, which prevents leakage past the threads from either side of your application. These rivet nuts have a ribbed body to hold them in place when tightening a screw. The body and flange are zinc yellow-chromate plated steel for corrosion resistance. Install in a drilled hole using a rivet nut tool. The tool collapses the nut, creating a backside flange that holds the nut to the material. Length is measured from under the flange. Installed length is the maximum length of the barrel when installed.

Closed-end inserts offer the advantage of offering a 100% watertight connection, meaning the thread cannot be damaged by water or dirt.

In particular, these rivet nuts are safe for electrical circuits since no fluids can get in.

Fast Facts:

Blind hole, one-sided installation capability.

Provide load-bearing threads in sheet materials.

Offers a water- and air-sealed connection.

It is suitable for use in electrical circuits and in any applications (containers, tanks, airco systems) where a water-sealed connection is needed.

Available in stock in steel. Other materials are available on demand.