CPVC full form in plumbing is Chlorinated Polyvinyl Chloride which means more chlorine has been added to PVC. CPVC products are thermoplastic and are made with CPVC resins. They are one of the strongest and durable materials used in the plumbing applications for more than 50 years now. CPVC is resistant to chemical, reliable, and can withstand high heat temperature to 93 degree C and pressure, thus making it an ideal material for residential, commercial, and industrial piping and fire sprinkler systems.
CPVC is widely used in,
CPVC pipes are ideal for hot and cold water distribution in residential and industrial projects. They are used to carry drinking water and food liquids and are also used in water treatment plants.
CPVC pipes are used in industrial plumbing for chemicals. They are used in the transportation of chemicals and hot corrosive fluids that includes a wide range of inorganic acids, bases used in the chemical processing.
Each step in making CPVC is critical. From raw material to PVC, PVC to CPVC, from CPVC to finished product. In the first step, petroleum is put in a cracker and then ethylene is extracted from it. Manufacturers then react to the two chemicals chlorine and ethylene to form a new liquid chemical known as ethylene dichloride.
The EDC is dehydrated through an oxychlorination process and is ultimately broken down into Vinyl chloride monomer (VCM) .Then VCM is then polymerized in a high-pressure reactor to form Polyvinyl chloride. Then PVC resin is manufactured. The PVC is then subjected to the chlorination process.
Polyvinyl chloride is chlorinated through a free radical chlorination reaction. CPVC is then produced by adding chlorine to PVC in a fluidized bed chlorination process. The chlorination process is then initiated by ultraviolet light. The CPVC is compounded with the necessary ingredients and is further processed. Because of extra chlorination CPVC is suitable for hot water plumbing systems.
BASIC PROPERTIES OF CPVC
|PROPERTY||TEST||CONDITION||ENGLISH UNITS||SI UNITS|
|Specific Gravity||ASTM D 792||23°C||1.55||1.55|
|Specific Volume||23°C||0.645 Cm3 / g||0.645 Cm3 / g|
|Water Absorption||ASTM D 570||23°C||+0.03%||+0.03%|
|Rockwell Hardness||ASTM D785||23°C||119|
|Cell Class||ASTM D 1784||23447|
|Izod Impact||ASTM D 256||23°C||1.5 ft lbs/in o.n.||80 j/m o.n.|
|Tensile strength||ASTM D 638||23°C||8000 psi||55 N/mm2|
|Tensile Modulus||ASTM D 638||23°C||360,000 psi||2500 N/mm2|
|Flexural Strength||ASTM D 790||23°C||15,100 psi||104 N/mm2|
|Flexural Modulus||ASTM D 790||23°C||415,000 psi||2860 N/mm2|
|Compressive strength||ASTM D 695||23°C||10,100 psi||70 N/mm2|
|Compressive Modulus||ASTM D 695||23°C||196,000 psi||1350 N/mm2|
|Coefficient of Thermal Expansion||ASTM D 696||6.1×10-5 m/m/k|
|Thermal Conductivity||ASTM C 177||0.14 Wm/k/m2|
|Heat Distortion Temperature||ASTM D 648||103° c|
|Heat Capacity||DSC||23°c||0.90 j/gk|
|Flammability Rating||UL 94||0.062 in/0.157cm||V-0 , 5VB , 5VA|
|Flame Speed||ASTM E84||15|
|Smoke developed||ASTM E84||70-125|
|Limiting Oxygen Index||ASTM D 2863||60%|
|Dielectric Strength||ASTM D 147||1250 V/mil||4,92000 V/cm|
|Dielectric Constant||ASTM D 150||60 Hz,-1°c||3.7||3.7|
|Power Factor||ASTM D 150||1000 Hz||0.007 %||0.007 %|
|Volume Resistivity||ASTM D 257||23°c||3.4×1015 ohm/cm||3.4×1015 ohm/cm|
CPVC has the ability to self-extinguish and does not catch fire when exposed to fire because of the high limiting oxygen index (i.e. 60). It does not burn but turns carbonized black when heat is applied.
CPVC has a smooth inner surface. Hence C factor is very high as compared to Copper, Steel & GI (i.e. 150). Higher C value means less friction, less head loss and no scaling.
CPVC is resistant to corrosion, rust and tube clogging. CPVC is resistant to chemicals like acids, bases, salts and halogens.
CPVC is non toxic and antibacterial.Certified by NSF. Hence it is suitable for potable water systems.
Simple solution jointing system. No special tools required for jointing. Easy repairable/modifiable after installation.
Solvent Cement used for CPVC jointing & the process called Cold Welding Process.
CPVC has much higher strength than other thermoplastic used in plumbing applications. Hence it requires less support, no snaking, suitable for vertical plumbing & high pressure bearing capacity.
Less expansion of CPVC pipe when hot water runs. Hence less expansion loop required & less looping & snaking.
CPVC has low thermal conductivity and possesses excellent warming and cooling effects with no condensation.
CPVC plumbing system has very good UV resistant property. Hence limited to a surface discoloration, no breakdown of polymer chain, no significant loss in pressure bearing capacity. For further protection apply a single coat of water base paint if it is exposed to sunlight.
Chlorine, a commonly used chemical to treat water in India is corrosive in nature. CPVC is unaffected by chlorine in water supply.
Additives in CPVC material do not migrate into water even after a long period of water stagnation.
Very Low noise effect due to water hammer effect. Much quieter than the metallic system.