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.
Pierce nut technology from Bulten is an attractive alternative to weld nuts in many applications.
The ability to complete a component in the press line eliminates secondary operations such as welding of nuts and intermediate storage of components between press and welding stations.
The elimination of welding operations makes the working environment cleaner and saves energy.
Product quality is improved, since the positioning of the pierce nut is more exact and causes no damage to pre-surface finished plates.
Shorter lead times, reduced investment costs and improved quality control make production more cost-effective. Pierce nut stamping is generally about 30% more economical than weld-nut attachment.
Pierce nuts are suitable in all applications where nuts are to be fitted in sheet metals. Pierce nuts are frequently used in a wide range of industrial applications such as, automotive, household appliances, white goods and enclosures.
Bulten’s BUFO® Pierce Nut System is designed to reduce in-place cost by making nut insertion much easier and cost effective. The BUFO® Pierce Nut punches its own hole and eliminates pre-hole punching. This process is performed directly in the press line, thereby excluding any secondary insertion operations.
The round shape of the BUFO® pierce nut, coupled with the angled and serrated fixing portion, gives more contact between plate and nut, increasing the mechanical strength of the joint compared to earlier pierce nut designs.
The BUFO® Pierce Nut System can be adapted to suit single or multi operation press lines.
The Pierce Nut System was first introduced to the Japanese automotive industry by Aoyama Seisakusho Co. Ltd. in the late eighties and has been subsequently further developed, and is now used within the European automotive industry.
The BUFO® pierce nut range covers a wide variety of industrial applications, including assemblies of high strength steel and soft alloys, as well as compact variants for compact designs and low weight.
The BUFO® Pierce Nut is not just a pierce nut, it is a complete solution.
Unique angled and serrated fixing portion results in:
- High torsional resistance
- High pull through force
- High push out force
Completion of component in press line which:
- Reduces in-place cost
- Saves costs of intermediate storage
- Eliminates secondary operations
- Shortens lead time
- Eliminates annealing associated with nut welding
- Self clinching – eliminates eye lidding
- Allows multiple nuts (≤ 20) to be installed in a single stroke
Use of gas spring insertion method which gives:
- Controlled setting force
- Optimal torsional resistance
- Optimal pull through force
- Optimal pull out force
- Allows generous stamping process window compensation
Are suitable to combine with TAPTITE® Thread Rolling Screws which:
- Gives prevailing torque function
- Eliminates plugging of nuts to be painted
- Eliminates paint clearing of threads
- Eliminates risk of cross threading
Can replace weld nuts which:
- Gives a cleaner working environment
- Saves costs for intermediate storage
- Shortens lead time
- Eliminates costs for welding
- Eliminates weld splatter and the need for retapping
- Improves quality of product due to non-oxidation of plates as product is not welded
- Eliminates gap between nut and sheet metal
- Facilitates for usage in pre-surface treated material
- Enables use in aluminium plates where weld nuts are not an alternative