What Are The Differences In Connection Methods Between PP And PVC Pipes?

The PP and PVC pipes produced and manufactured by Longchang Jie Machinery Co., Ltd. have certain differences in their connection methods. The main differences lie in the applicable scenarios, technical approaches, and core distinctions.

1. Core connection method comparison

Based on the pipe type, describe the main connection methods, applicable scenarios, and key technical requirements from three aspects: main connection methods, applicable scenarios, and key technical requirements.

PP pipes: Main connection methods : Hot melt connection (preferred);Electrofusion connection ;Flange connection, thread connection (secondary) Applicable scenarios: Connection between homogeneous PP pipe materials and pipe fittings; Flanges for large-diameter pipes, threads for small-diameter pipes. Key technical requirements: Hot melt requires heating to a specific temperature (usually 190-240℃) to melt the pipe material ； Electrofusion uses built-in resistance wire heating.

PVC pipes： Main connection methods :Sealing rubber ring interface (≥100mm pipe diameter);Adhesion (<100mm pipe diameter);Flange connection (with metal pipes or valves) Applicable scenarios： Drainage， water supply pipes； Use adhesive for small-diameter pipes， rubber ring for large-diameter pipes； Use flange when crossing other pipes or connecting valves. Key technical requirements： Adhesion requires rounding the socket corners and applying special solvent glue； Sealing ring interface requires cleaning the socket and rubber ring to ensure sealing.

2. Key differences analysis

1. Connection principle is different

PP pipes： Depend on thermoplastic melting to achieve molecular-level bonding， suitable for connection of the same material (polypropylene)， with high connection strength and good sealing performance.

PVC pipes： Through physical sealing (rubber ring) or chemical bonding (solvent glue dissolves the surface and then cures)， suitable for transition connections between PVC pipe materials or with metal parts.

2. Tools and costs

PP pipes： Require professional hot melt machines， electrofusion welders， with high initial equipment investment but low long-term maintenance costs.

PVC pipes： Adhesion only requires glue and brush， rubber ring interface requires a sealing ring， lower cost， but the adhesive may release harmful substances (need ventilation treatment).

3. Compatibility limitations

PP pipes' hot melt/electrofusion only apply to homogeneous PP materials. If connecting with PVC， use flange or thread connection as a transition joint， and use sealing parts (such as rubber gaskets).

PVC pipe adhesion is only applicable to PVC， suitable for PVC-PVC connections， requires additional conversion accessories， and pay attention to the difference in thermal expansion coefficients of the two materials (PP has better heat resistance than PVC， and long-term high temperature is prone to interface leakage).

3. Special scenarios handling

Different material connection： If PP pipes and PVC pipes need to be directly connected， use flange connection (metal or plastic flange disc + bolt tightening)， and add a sealing gasket on the contact surface to avoid sealing failure due to material differences.

Hidden project attention： If PVC pipes are buried， it is recommended to bury tracking wires above for later detection； PP pipes due to high reliability of hot melt connection， no additional marking is needed.

Summary

The connection of PP pipes is mainly based on hot-melt or electro-melt technology, suitable for scenarios with high temperatures, high pressures or strict hygiene requirements (such as hot water supply, chemical pipelines); PVC pipes mainly use rubber rings or adhesion methods, suitable for low-cost, normal-temperature drainage or non-drinking water systems. For cross-material connections, transitional methods such as flanges are used to ensure compatibility and sealing.