National Plastic Sharjah

3.6

Properties	Typical Values	ASTM Testmethod
Mechanical
Specific Gravity	1.40, 1.44	D-792
Tensile Strength, psi @ 73.4°F	7000	D-638
Tensile Modulus, psi	400,000	D-638
Allowable Fibre Stress, psi @ 73.4°F	2,000
Flexural Yield Strength, psi	13,000	D-790
Izod Impact, ft.lbs./in. Notched @ 78°F	0.65, 1.50	D-256
Durometer Hardness	77.83	D-2240
Thermal
Coefficient of Thermal Conductivity Cal. Cm/Sec. Cm²C°	3.5x10^-4	C-177
Coefficient of Linear Expansion, in/in/C°	6.4x10^-5	D-696
Heat Distortion at °F @ 264 psi	158 °F	D-648
Electrical
Dielectric constant 10³ cps at 30 °C	D-150
Dielectric Strength, short-time, 1/8 in thickness, volts/mil	490	D-149
Other properties
*Burn Rate in./min.	AEB Less than 25mm ATB Less than 10sec.	D-635
Water Absorption, 24hr, 1/8 in thickness, %	0.5-3.0	D-570
ASTM CELL CLASSIFICATION	12454B	D-1784

Points to be considered when installing National Plastic ASTM pipe

When using Solvent Weld Joints, use a quality grade of primer and slovent cement and follow the established code of practice.
When using Rubber Ring Joints use an approved lubricant to lubricate the spigot and ring prior to insertion.
Adequate thrust restraint is necessary especially for gasketed joint systems. Thrust blocks should be installed at all directional changes and take into account the soil load bearing values.
Bedding and initial back fill should be free of large rocks or particles that can damage the pipe. The bottom of trenches should be level to support the pipe uniformly.
Pipe should not be left exposed to ultra violet conditions for extended periods of time and should be backfilled as soon as possible after installation.
Ensure adequate allowance is made for the expansion and contraction of the pipeline. The co-efficient of thermal expansion of uPVC is much greater than other materials and must be considered when installing. The co-efficient is approximately 1mm/m 15°C. Pipe should be backfilled in cool conditions.
Selection of pressure rating and class of pipe should be based on consideration of all factors which may affect operation of the pipeline e.g temperature of operation, fluctuating pressure and external loading.
Adequate air relief valves should be installed in all piping systems.
The design of a pipeline system should take into account the possibility of water hammer and surges occuring during service. The designer must ensure adequate protection by way of pressure relief valves, slow opening valves and air relief valves. These should be incorporated into the design of any closed pressurized system.
uPVC Pipe systems should not be used for compressed air service.