WHAT IS NECKING-IN?
Necking is a hot rotary forming process used to close tube ends by progressively deforming the material at high temperature.
The process allows tubes to be closed without welding, producing sealed bottoms or necks suitable for high-pressure applications, with forming temperatures that can exceed 1,000 °C depending on the material.
Why choose necking?
WELD-FREE CLOSING
Produce closed tube ends without welding, reducing weak points and improving pressure resistance
HIGH-TEMPERATURE FORMING
Designed to work with parts at very high temperatures, allowing controlled deformation of steel and other materials used in pressure vessels
CRACK PREVENTION BY DESIGN
An inert gas injection system developed by DENN prevents oxidation during bottom closing, avoiding micro-cracks in critical areas
Have questions?
Send us a plan and we’ll confirm feasibility, with no obligation.
Quick fit check
IS NECKING RIGHT FOR YOUR PART?
For you if
– You need to close tube ends without welding
– The container must withstand high internal pressure
– Your process allows hot forming at elevated temperatures
– You require controlled, repeatable neck or bottom geometries
Not the best if
– The part cannot be processed at high temperatures
– Welding is mandatory by design or regulation
Quick design check
– Define whether the operation is neck forming, bottom forming, or both
– Confirm material type and required forming temperature
– Identify sealing and pressure-test requirements early
– Specify any secondary operations (e.g. drilling, threading after forming)
Send us to confirm
– 2D drawing or 3D model
– Material and tube dimensions (diameter, thickness)
– Target neck/bottom geometry and sealing requirements
– Batch size and annual forecast
APPLICATIONS
Spinning technology is applied in various sectors:
FEATURED PROJECTS
Success Stories
DESIGNED FOR
ACCURACY & EFFICIENCY
LET'S TALK ABOUT YOUR PROJECT
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- Phone Number
- (+34) 937 13 20 01
- denn@denn.es
- Address
- Calle del Pintor Vila de Cinca, 30. 08213 Barcelona
