PVC or polyvinyl chloride is an engineering plastic with excellent ultraviolet (UV) resistance, insulating properties, and resistance to moisture ingress. This makes it a popular choice for piping and construction materials, as well as for the electrical, energy, and medical industries.
PVC is one of the most widely used engineering plastics. It generally comes in two forms: plasticized and unplasticized PVC. Unplasticized PVC is used in rigid parts like pipes and fittings. CNC machining in PVC is generally done with this rigid version of the material. Plasticized PVC is used in applications that require flexibility like cables or small tubes. The production of PVC uses fewer nonrenewable raw materials by volume than most other plastics, making it one of the greenest plastics available. CNC machining in PVC is similar to that of other engineering plastics, and thanks to its rigidity and hardness, it machines relatively easily.
|Application||Bushings, wear parts, electrical components|
|Advantages||Low moisture absorption, electrical insulator, good fire retardant|
|Disdvantages||Not well suited to temperatures below 14℉ or above 176℉ (-10℃ and 80℃, respectively)|
|Lead Time||3 days minimum|
|Tolerances||Machining tolerances of 0.01” (0.26 mm) are achievable.|
|Wall Thickness||A minimum wall thickness of 0.03” (0.8 mm) is achievable. This can vary depending on the ratio of wall thickness to planar dimension.|
CNC machining in PVC results in low-cost parts that have excellent mechanical properties and come with the added benefit of being resistant to the elements. The material’s moisture and UV resistance make it attractive for applications like piping and pipe fittings.
|Tensile Strength, Yield (MPa)||Elongation at Break (%)||Hardness (Shore D)||Heat Deflection Temperature (°C)||Flammability Rating (UL 94 (1.5 mm))|
Unlike most other engineering plastics, PVC can be readily painted both for aesthetic purposes as well as to further increase its outdoor lifespan. It must also be noted that though its mechanical properties remain consistent, transparent PVC tends to discolor over time when exposed to the sun or other UV sources.
CNC machining in PVC produces lightweight and low-cost components. Nevertheless, the following tip can help minimize costs even further: