In plastic pipe production, extrusion is only part of the manufacturing process. For pipes such as PVC drainage pipes, water supply pipes, and large-diameter sewer pipes, the pipe ends must be expanded into a socket structure so that pipes can be connected reliably.
This is where a Pipe Belling Machine—also known as a Pipe Socketing Machine or Pipe Expanding Machine—becomes essential.
A pipe belling machine is designed to heat and expand the pipe end to form a bell (socket) shape, ensuring secure jointing and sealing performance in pipeline systems.
A Pipe Belling Machine is a downstream auxiliary machine used in plastic pipe extrusion lines. It forms a socket (bell) on the pipe end by controlled heating and shaping with molds.
According to the product information in the image, the SGK series includes:
Automatic Pipe Belling Machine
Semi-automatic Pipe Belling Machine
Matching mould systems
Integration capability with complete pipe extrusion lines
It can be connected directly to pipe production lines or used independently.
Without a socket structure:
Pipes cannot be easily connected.
Sealing reliability is reduced.
Installation efficiency decreases.
Structural stability of pipeline systems is compromised.
Belling creates:
Tight-fit joints
Sealing ring installation space
Faster on-site installation
Standardized connection systems
For PVC pipes especially, vacuum-type belling ensures dimensional precision.
Integrated heating, forming, cooling
PLC controlled
Suitable for large-scale pipe production lines
High efficiency and consistency
Operator-assisted loading
Lower investment
Ideal for small to medium production volumes
According to the technical data:
Double pipe belling (for smaller diameters)
Vacuum belling type (for larger diameters)
Cooling methods: wind cooling or water cooling
Vacuum belling provides higher precision and smooth socket finish, especially for large-diameter PVC pipes.
| Model | Pipe Diameter (mm) | Belling Method | Cooling Type | Heating Power (kW) | Total Power (kW) |
|---|---|---|---|---|---|
| SGKS63 | Φ20–63 | Double Pipe | Wind/Water | 4 | 5.53 |
| SGK250 | Φ63–250 | Vacuum | Water | 4 | 10.1 |
| SGK315 | Φ110–315 | Vacuum | Water | 7.2 | 12.1 |
| SGK400 | Φ160–400 | Vacuum | Water | 15.6 | 22 |
| SGK630 | Φ315–630 | Vacuum | Water | 25.4 | 36.2 |
| SGK800 | Φ630–800 | Vacuum | Water | 32 | 60 |
This range covers pipe diameters from 20mm up to 800mm, suitable for drainage, water supply, and large municipal pipeline systems.
Pipe enters belling station
Pipe end is heated evenly
Mold expands the pipe into socket shape
Vacuum ensures dimensional precision
Cooling stabilizes the structure
Finished pipe exits the machine
Temperature control and forming time are critical factors for socket quality.
PVC drainage pipes
PVC water supply pipes
Large diameter sewer pipes
Electrical conduit pipes
Agricultural irrigation pipes
| Feature | Automatic | Semi-Automatic |
|---|---|---|
| Labor Requirement | Low | Medium |
| Production Efficiency | High | Moderate |
| Investment Cost | Higher | Lower |
| Recommended For | Continuous extrusion lines | Independent workshops |
Mainly PVC pipes. Some models can be adjusted for other thermoplastic pipes depending on material characteristics.
Up to Φ800mm according to the SGK series specifications.
Vacuum belling provides higher precision and is typically used for medium and large diameter pipes. Double pipe belling improves efficiency for small-diameter pipes.
Yes. The SGK series can be integrated into a complete pipe extrusion production line.
Heating uniformity, mold precision, vacuum stability, and cooling efficiency.
As a professional plastic pipe extrusion equipment manufacturer, Chenxing Machinery provides:
Complete pipe extrusion line solutions
Integrated automatic belling systems
Customized mould design
Stable temperature control technology
Reliable vacuum forming system
Technical support and installation guidance
Our pipe belling machines are engineered for long-term industrial use with stable output and precise socket formation.
If you are planning a PVC pipe production line or upgrading your existing downstream equipment, our technical team can provide a tailored solution.
Visit: www.chenxingmachinery.com
Contact us for detailed machine specifications and quotation.
