Residential hot water
PPR handles continuous 70°C service and short-term 95°C peaks in household plumbing.
PIPE EXTRUSION
How PPR Pipe Is Made
From polypropylene random copolymer to hot water plumbing pipe.
PPR pipe is a plumbing product for hot and cold water systems. It is chosen because random copolymer polypropylene gives better impact resistance and long-term creep resistance than homo-PP in building water systems.
What PPR pipe is used for
PPR pipe is rated by pressure and temperature. A PN20 pipe may be suitable at 20°C but derates near 60°C because long-term hydrostatic strength decreases as water temperature rises.
Commercial HVAC
Hotels, offices and hospitals use PPR for circulating water and utility pipe networks.
Underfloor heating
Small-diameter PPR or PP-RCT pipe is used where stable dimensions and clean joints matter.
Industrial chemical lines
Selected low-pressure chemical transfer systems use PP-based pipe for corrosion resistance.
Raw material: PPR granules
PPR stands for polypropylene random copolymer. The random ethylene units lower crystallinity, which improves low-temperature impact strength and high-temperature creep resistance compared with homo-PP. PPR pipe factories usually buy ready-to-process granules; no dry blending is required. Pigment masterbatch is added for colour — green is common in China and the Middle East, while white or grey is common in Europe.
- PPR is thermally stable enough for single-screw extrusion at about 200-220°C.
- The material should be clean and dry, but it is much less moisture-sensitive than PC or PET.
- Pipe fittings are normally injection moulded, not extruded, so fitting production requires separate injection equipment.
Production process
PPR production looks similar to PE pipe production, but dimensional control is tighter for plumbing pipe because pipe and socket fittings must weld reliably. Dry sizing is often preferred at the first calibration stage to avoid thermal shock on the hot pipe surface.
Granule feeding
PPR granules and colour masterbatch are fed into the extruder. Consistent dosing avoids colour streaks and pressure fluctuation.
Single-screw extrusion
A single-screw extruder with L/D 25:1-30:1 melts the material at 200-220°C. PPR does not require twin-screw plasticizing because it is less heat-sensitive than PVC.
PPR pipe die
The die forms the pipe wall and bore. Die centering is important because uneven wall thickness affects pressure rating and socket fusion quality.
Dry sizing
Dry sizing is preferred for many PPR lines because sudden water contact can mark the surface or create uneven shrinkage. It stabilizes the OD before the water tanks.
Cooling tank
Water cooling sets the pipe dimensions gradually. Cooling length depends on pipe diameter and line speed.
Haul-off
A belt or caterpillar haul-off controls pipe wall thickness by pulling speed. Stable speed is required to keep PN wall thickness within tolerance.
Cutting
A guillotine or planetary cutter cuts pipe to standard lengths. Smooth cut ends are important because PPR pipe is commonly socket-fused on site.
Finished pipe requirements
PPR pipe is commonly rated PN10, PN16, PN20 or PN25. The rating must be interpreted with service temperature: long-term strength falls as temperature rises, so hot-water applications need thicker wall or higher grade material than cold-water lines. Finished pipe is checked for OD, wall thickness, opacity, longitudinal reversion, hydrostatic strength and surface quality.
Machines required
These are the core machines for a PPR pipe line. If the project also needs elbows, tees and sockets, those fittings are made by injection moulding and should be planned separately.
Single Screw Extruder
Melts PPR granules with stable pressure and controlled temperature.
PPR Pipe Die Head
Forms the pressure pipe wall and bore.
Dry Sizing & Cooling Tank
Controls OD and cools the pipe without surface shock.
Haul-off Unit
Sets line speed and wall thickness.
Pipe Cutter
Cuts PPR pipe cleanly for socket fusion and packaging.
Technical reference
Planning reference only. Final configuration depends on your target spec — share it with the engineering team for a matched proposal.
| Pipe diameter | Ø20-160mm |
|---|---|
| Output rate | 40-300 kg/h |
| Pressure rating | PN10 / PN16 / PN20 / PN25 |
| Line speed | 1-12 m/min |
| Processing temperature | 200-220°C |
| Material | PPR / PP-RCT / PP-H variants |
Ready to produce PPR pipe?
Share your PN rating, pipe diameter range, material grade, colour and output target. The engineering team will return a matched extruder, die, sizing and cutting layout within 24 hours.
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