What’s the difference of GRE, GRP, GRVE Pipe?

GRE (Glass-Reinforced Epoxy) pipes, GRP (Glass-Reinforced Plastic) pipes, and GRVE (Glass-Reinforced Vinyl Ester) pipes are all composite pipes. Their main differences are as follows:

GRE pipes are made of epoxy resin as the matrix and glass fiber as the reinforcement. Epoxy resin has excellent adhesion, corrosion resistance, and mechanical properties, giving GRE pipes high strength and stability.
GRP pipes, commonly known as fiberglass reinforced plastic pipes, are made of glass fiber and its products (such as glass cloth and glass mat) as the reinforcement and a synthetic resin (such as unsaturated polyester resin and epoxy resin) as the matrix. The type of resin can be selected according to specific needs, and the material range is relatively wide.
GRVE pipes are made of vinyl ester resin as the matrix and glass fiber as the reinforcement. Vinyl ester resin is produced by the ring-opening addition reaction of epoxy resin and methacrylic acid. It combines the high strength and corrosion resistance of epoxy resin with the fast curing properties of unsaturated polyester resin.

Performance Characteristics:
GRE pipes: Offer excellent axial and circumferential mechanical values and high mechanical strength. They are resistant to seawater, brackish water, and mildly corrosive liquids. They are adaptable to a wide range of media, with the exception of strong alkalis and acids, and exhibit good chemical resistance, particularly to hydrocarbons and BTX (benzene, toluene, and three xylene isomers).
GRP pipes: Offer excellent corrosion resistance, resisting corrosion from a variety of chemicals, including acids, alkalis, and salts. They are lightweight and easy to transport and install. However, the performance of GRP pipes varies depending on the resin matrix, and their overall mechanical strength and pressure resistance may be slightly lower than those of GRE pipes. However, they can meet general water supply and drainage, building drainage, and other requirements.
GRVE pipes: Offer excellent corrosion resistance, have no impact on water quality, and do not require anti-corrosion measures such as cathodic protection. Lightweight and high-strength, they are significantly lighter than steel pipes of the same length. They have a smooth interior surface, good flow capacity, and excellent low-temperature performance and thermal insulation.

Applications:
GRE pipes: Suitable for applications requiring high reliability, such as marine and offshore applications, the oil and gas industry, and the petrochemical industry. They are often used in utility applications like cooling and fire protection systems. They can also be used for fluid transport requiring high mechanical strength and corrosion resistance.
GRP pipes: Widely used in water supply and drainage systems and fire protection piping systems in the building industry, such as drainage systems for roofs and basements, as well as drainage and water supply pipes in municipal engineering projects. They can also be used in applications where pressure requirements are not particularly high, such as agricultural irrigation.
GRVE pipes: Primarily used in fire protection, water supply and drainage systems, they are widely used in international terminal projects. They can be used for fire water, produced water, and sewage systems, ranging from low to high pressure.

Connection Methods:
GRE pipes: A variety of connection technologies are available, including adhesive bonding, (un)constrained O-ring connections, screw connections, and laminated connections for repairs or joints.
GRP pipes: Common connection methods include socket joints, flange connections, and adhesive bonding. The choice depends on the project requirements and pipe specifications. GRVE pipes: They are mainly connected by hand-paste bonding process, with the pipe parts bonded together by materials such as resin and curing agent. O-ring connection and lamination connection can also be used.