Uses, Working Principle and Common Problems of Automatic Rivet Nut Guns - BISUDI

Pull rivet nuts (rivet nuts, threaded rivet studs) are fasteners specifically designed for thin plates and tubes, forming reliable internal threads on the plate surface, which can then be repeatedly assembled and disassembled with ordinary screws. Automatic rivet nut guns are the equipment that automates this process. First-time customers are most concerned about three things: what products it can be used on, how exactly it forms, and what to do when problems arise. This article explains all at once.

I. Uses: Solving the thread problem on thin plates

Direct tapping on thin plates (usually within a few millimeters) results in few thread teeth and easy thread stripping; welded nuts have problems of thermal deformation, weld spatter and false welding, and cannot be applied when the backside is inaccessible. Pull rivet nuts use cold deformation to "grow" a thread base on the plate, with four irreplaceable features: single-side construction, can operate even with closed backside; belongs to cold working, no thermal deformation, does not damage surface treatment; the formed internal threads can be repeatedly assembled and disassembled with screws; can be assembled after painting or coating, avoiding threads being clogged by coating.

II. Working principle (five-step forming)

Step 1, nuts are automatically sorted and screwed onto the gun head screw; Step 2, gun head is aligned with the pre-drilled hole and inserted vertically, nut body passes through the hole; Step 3, start riveting, gun head pulls axially, nut bulges and deforms on the backside of the plate and presses against the plate surface; Step 4, maintain pulling force to set the deformation, forming a firm thread base; Step 5, screw reverses and withdraws, one internal threaded hole is completed, then screw in a screw afterwards. The whole process requires no welding and no backside operation.

III. Comparison of pull rivet nuts with other thin plate thread solutions

IV. Common problems and causes

Thread stripping/screw cannot tighten:Screw wear, hole diameter too large or plate thickness exceeds nut riveting range;Cannot bulge, loose spinning nut:Insufficient air pressure, insufficient stroke/pulling force setting, hexagonal hole not matched;Plate surface depression:Excessive pulling force, gun head not flat or plate too thin;Screw cannot withdraw:Screw broken teeth, nut not fully formed or insufficient lubrication;Thread not go-through:Nut specification inconsistent with screw, nut follows rotation during riveting. System troubleshooting method seeRivet Nut Gun Common Faults and Installation Problem Troubleshooting。

Uses and Principle FAQ

V. Process parameters to confirm before purchasing

Before inquiring or applying for trial from the manufacturer, it is recommended to organize the following parameters clearly at once: plate material and thickness (including number of stacked layers), current status of pre-drilled holes (round or hexagonal holes, actual hole diameter), nut specification and material (M size, steel/aluminum/stainless steel, flat/countersunk head, through/blind hole), number of rivet points per piece and annual output, screw assembly torque requirements, whether there are sealing or appearance requirements. The more complete the parameters, the more accurate the selection - for the same M6 nut, 0.8mm cold-rolled plate and 3mm stainless steel plate correspond to completely different models, pulling forces and pre-drilled holes. When information is complete, the manufacturer can give a solution and price range in about 10 minutes; for special requirements involving blind hole sealing, hexagonal anti-rotation, etc., it is recommended to directly send sample pieces for trial riveting and do pull-out tests.

Further reading:Through-hole and Blind-hole Rivet Nut Operation Points · Application of Automatic Rivet Nut Guns in Sheet Metal Processing · Automatic Rivet Nut Gun