Pierce nut system - for cost-efficient joints
Bulten’s BUFO® self-clinching pierce nut system offers several advantages in terms of in-place cost, working environment and productivity.
Introducing a pierce nut assembly system involves everything from feeding system to stamping equipment, press integration and the nut itself.
Bulten offers a complete pierce nut system including the machinery, nuts and technical support needed to maximise productivity and ensure a quality controlled assembly line.
Compared to weld nut, the pierce nut has the following advantages:
- Saves electricity
- No smoke
- No weld splatter, which eliminates re-tapping of the nut
- Avoids intermediary steps between the pressing and welding stations
- Reduces lead times
- Avoids difficulties with coated sheet metal
- More secure orientation of the nut against sheet metal and a more exact right-angle, thus avoiding misassembly such as positioning.
In comparison to square pierce nuts, there are also further advantages:
- Easier feeding and less risk of the nut getting stuck in the feeding system
- More even distribution of pressure between nut and sheet metal
- No stress concentrations due to sharp corners
- Reduced risk of stress cracks in the sheet metal
If an unthreaded pierce nut will be combined with thread rolling screws, such as taptite®, a further reduction of In Place Cost is achieved, thanks to:
- Eliminates risk of cross threading
- Not necessary to plug or mask the nut hole
- Not necessary to clean threads after painting or other surface treatment
- A more vibration resistance joint is obtained
- Additional locking features are not needed
Another advantage of the bulten system for round pierce nut is the use of a gas spring when mounting the nut. This system gives the following advantages:
- Controlled setting force
- Optimal torsional resistance
- Optimal pull through force
- Optimal push out force
- Allows generous stamping process window compensation
Mounting the pierce nut is a straight forward, one step process. The nut, forced by the punch, makes its own hole through the sheet metal and the die ensures a solid attachment of the pierce nut.