CPVC · grade · default condition
CPVC Unfilled
Properties of the Unfilled condition, compared with the other CPVC grades.
Default choice for pipe, fittings, sheet and machined parts in hot corrosive service to ~93 °C.
What is CPVC Unfilled?
CPVC Unfilled is CPVC in the Unfilled grade — default choice for pipe, fittings, sheet and machined parts in hot corrosive service to ~93 °C. CPVC Unfilled has a yield strength of 52 MPa (7.54 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 52% of polymer grades. Elongation at break is 25% and the elastic modulus is 3 GPa (0.435 Msi). CPVC Unfilled has a density of 1.54 g/cm³ (0.0556 lb/in³), heavier than 89% of polymer grades. Its glass-transition temperature is 115°C (239 °F).
Advantages
- Low moisture uptake — 0.04%, better than 86% of polymer grades
- Low embodied carbon — 3 kg CO₂/kg, better than 84% of polymer grades
- Easy to machine — 75/100, better than 78% of polymer grades
- Good UV / weathering resistance — 55/100, better than 77% of polymer grades
Limitations
- Heavy — 1.54 g/cm³ (0.0556 lb/in³), worse than 89% of polymer grades
- Poor heat conductor — 0.14 W/m·K (0.0809 BTU/hr·ft·°F), worse than 81% of polymer grades
CPVC Unfilled properties
Typical room-temperature values for CPVC Unfilled — 7 properties are specific to this condition; the rest are grade-level values shared by every CPVC grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.
Physical5
CPVC Unfilled has a density of 1.54 g/cm³ (0.0556 lb/in³), heavier than 89% of polymer grades. Its glass-transition temperature is 115°C (239 °F).
Mechanical14
CPVC Unfilled has a yield strength of 52 MPa (7.54 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 52% of polymer grades. Elongation at break is 25% and the elastic modulus is 3 GPa (0.435 Msi).
Thermal11
CPVC Unfilled is rated for continuous service to 93°C (199 °F). It conducts heat at 0.14 W/m·K (0.0809 BTU/hr·ft·°F), worse than 81% of polymer grades. Thermal expansion is 68 µm/m·K (37.8 µin/in·°F).
Electrical6
CPVC Unfilled is an electrical insulator with a dielectric strength of 22 kV/mm (558.8 V/mil) and a resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 63% of polymer grades. UV resistance is good.
Sustainability4
Producing a kilogram of CPVC Unfilled takes about 75 MJ of energy and emits 3 kg of CO₂ — less than 91% of polymer grades. Typical recycled content is 0%.
Manufacturability7
CPVC Unfilled's machinability is very good (75/100, better than 78% of polymer grades); weldability good (65/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other CPVC grades and fills
CPVC is also supplied in 5 other conditions. The full side-by-side table is on the CPVC overview.
- UnfilledDefaultDefault choice for pipe, fittings, sheet and machined parts in hot corrosive service to ~93 °C.55 MPa tensile
- GF20For structural fittings, valve bodies and duct components needing higher stiffness and lower creep/CTE at temperature.75 MPa tensile
- IMChoose where installation abuse or sub-ambient handling causes brittle cracking; trades some stiffness and HDT for toughness.48 MPa tensile
Working with CPVC Unfilled
Is CPVC easy to machine?
Machines easily with sharp, high-rake carbide tools, high speed and light feeds; use air or flood coolant to avoid heat build-up and gummy edges, and avoid deep unrelieved stress in threaded sections.
Can CPVC be welded?
Joined by solvent cement (CPVC-specific cement, not PVC) or hot-gas/hot-plate welding; never hot-melt butt-fuse like PE and never flame-heat, since >220 °C releases HCl.
Can CPVC be formed, bent or molded?
Extrudes and injection molds in a narrow window (185–210 °C melt, 40–75 °C mold) with corrosion-resistant screws/tools, generous venting and no hang-up; thermoforms at ~130–160 °C.
What surface finishes work on CPVC?
Not paintable without primer and not platable; parts are typically used as-molded, or lightly sanded/buffed—solvent wipe with ketones will craze the surface.
CPVC chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| chlorine (bound, of resin)characterizing parameter of CPVC resin, not a separate additive | 63 – 69 | 67 |
| tin/Ca-Zn heat stabilizerorganotin mercaptide typical for pipe compounds | 1.5 – 4 | 2.5 |
| impact modifier (acrylic/CPE)higher in impact-modified variants | 0 – 8 | 4 |
| process aid / lubricant (acrylic, wax) | 1 – 4 | 2 |
| TiO2 pigmentUV screening for outdoor pipe | 0 – 3 | 1.5 |
| vinyl chloride (post-chlorinated PVC bacbase resin; bound chlorine content 63–69 wt% of resin vs 56.7% for PVC | ≥ 88 (balance) | — |
CPVC Unfilled — frequently asked
What is CPVC Unfilled used for?
CPVC Unfilled is typically used for hot water plumbing pipe and fittings, fire sprinkler piping, chemical process piping and valve bodies, corrosive drain and vent lines, tank fittings and machined fluid blocks and duct and fume-handling sheet fabrications. In short: high-temp chlorinated PVC.
What is the yield strength of CPVC Unfilled?
CPVC Unfilled has a typical yield strength of 52 MPa (7.54 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 52% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is CPVC Unfilled easy to machine?
Yes — machinability is rated very good (75/100, better than 78% of polymer grades). Machines easily with sharp, high-rake carbide tools, high speed and light feeds; use air or flood coolant to avoid heat build-up and gummy edges, and avoid deep unrelieved stress in threaded sections.
Can CPVC Unfilled be welded?
Yes — weldability is rated good (65/100). Joined by solvent cement (CPVC-specific cement, not PVC) or hot-gas/hot-plate welding; never hot-melt butt-fuse like PE and never flame-heat, since >220 °C releases HCl.
What surface finishes work on CPVC Unfilled?
Not paintable without primer and not platable; parts are typically used as-molded, or lightly sanded/buffed—solvent wipe with ketones will craze the surface.
Can CPVC Unfilled be formed, bent or molded?
Extrudes and injection molds in a narrow window (185–210 °C melt, 40–75 °C mold) with corrosion-resistant screws/tools, generous venting and no hang-up; thermoforms at ~130–160 °C.
What is the maximum service temperature of CPVC Unfilled?
CPVC Unfilled is rated for continuous use to about 93°C (199 °F), and briefly to 105°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in CPVC Unfilled?
Yes — CPVC Unfilled is available for CNC machining, sheet metal and injection molding with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM D1784 — Rigid PVC and CPVC Compounds (cell classification) — ASTM (2020)
- ASTM F441/F441M — CPVC Plastic Pipe, Schedules 40 and 80 — ASTM (2020)
- ASTM F493 — Solvent Cements for CPVC Pipe and Fittings — ASTM (2020)
- Corzan CPVC industrial piping systems engineering & physical property data — Lubrizol (2023)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- CAMPUS / UL Prospector rigid CPVC compound datasheets — CAMPUS / UL (2024)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.