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As FRP Pipes have superior corrosion resistance capabilities and over the long term it is economic, Steel pipes are replaced by FRP pipes. So, in this section, it will be great to find the differences between FRP and Steel.

• Steel pipes are isotropic while FRP pipes are anisotropic and the properties changes with respect to direction.
• FRP pipes are more flexible than Steel pipes due to the lower modulus of elasticity.
• FRP piping systems are designed considering a higher factor of safety than steel piping. Usual factor of safety in the design of FRP pipes varies in the range of 5 to 10.

Other major differences between FRP and Steel pipes are provided in Table below:

PROPERTY	FRP	CS	REMARKS
Density	1850 kg/cu.m	7800 kg/cu.m	Loads on support are less in the case of FRP pipe as compared to Steel. Handling and transportation of FRP are easier than Steel pipes.
Co-eff of thermal expansion	27 X 10-6 mm/mm 0C	11 X 10-6 mm/mm 0C	Expansion is almost 2.5 times of Carbon Steel Pipe. So more thermal growth in case of FRP Piping system.
	* This value may change from vendor to vendor
Modulus	Axial= 12000 N/sq.mm	Elastic= 211365 N/sq.mm	Considerable difference in the strength of FRP & CS. Anchor loads are less in FRP Pipes as compared to steel pipes.
	Shear= 11400 N/sq.mm
Tensile Strength	80-135 MPa	456 MPa	Mechanical Strength is higher for Steel material as compared to FRP.
Yield Strength	70-135 MPa	227 MPa	The yield strength of FRP is lesser than that of Steel.
Allowable Stress	4,000 PSI to 20,000 PSI	20,000 PSI	The strength of GRE varies drastically and hence proper vendor data is a must.
Corrosion resistance	Superior	Inferior	The corrosion resistance of carbon steel is much lower than that of FRP pipes.
Joints	Threaded or glued	Welded	FRP joints are to be checked for higher axial loads and pressure

The initial cost of FRP pipes is normally higher than the metallic piping systems. But when comparing the total cost over the complete service life FRP Pipes come as a winner due to their long service life.