The ferrule is the primary seal
PP Compression Fittings use the ferrule (olive) as the primary seal. The ferrule is compressed onto the pipe. It deforms to create a watertight seal. Example: a brass ferrule sealing a PP pipe.
Ferrule material: brass
The ferrule is typically made of brass. Brass is durable and corrosion-resistant. It provides a reliable seal. PP Compression Fittings ferrules are often brass.
Ferrule material: plastic
Some ferrules are made of plastic. Plastic ferrules are for lighter applications. They are less common. PP Compression Fittings may use plastic ferrules.
No separate O-ring
PP compression fittings usually do not use an O-ring. The ferrule provides the seal. This simplifies the design. PP Compression Fittings are simple.
Sealing mechanism
The ferrule is compressed against the pipe. It deforms and fills gaps. This creates the seal. PP Compression Fittings seal through deformation.
Example: brass ferrule
A plumber uses a PP compression fitting with a brass ferrule. The ferrule compresses onto the pipe. The seal is watertight. PP Compression Fittings with brass ferrules are durable.
Example: plastic ferrule
A plumber uses a PP compression fitting with a plastic ferrule. The ferrule is for lighter duty. The seal is sufficient. PP Compression Fittings with plastic ferrules are for low pressure.
Ferrule reusability
The ferrule is deformed during installation. It should be replaced if the fitting is reused. PP Compression Fittings ferrules are single-use.
Seal material compatibility
Brass is compatible with most water and chemicals. Plastic ferrules may have limited chemical resistance. PP Compression Fittings materials must be compatible.
Temperature limits
Brass ferrules handle high temperatures. Plastic ferrules have lower temperature limits. PP Compression Fittings temperature limits depend on the ferrule.
Manufacturer specifications
Always check the manufacturer's seal material. Some may use special materials. PP Compression Fittings should be used per guidelines.
Final seal material summary
PP Compression Fittings use the ferrule as the primary seal. The ferrule is typically made of brass. Plastic ferrules are also available. No separate O-ring is used. Brass ferrules are durable and corrosion-resistant. PP Compression Fittings seals are simple and reliable. Example: choose the right ferrule material for your application.