Mechanical Properties Of Composites

Composites in general have far lower physical properties when compared to steel and lower physical properties than aluminum or brass. Composites can, however, be designed to withstand the operating pressures of a pump by increasing the section modulus of the part; that is, increasing the wall thickness. Table 3 shows some unreinforced composite properties versus steel. Figure 2 illustrates where the various composites and metallic are positioned and applied on a grid of developed pressure versus flow.

Thermoplastics PVC and CPVC pumps are low-cost and suitable for the lower temperature ranges. PVC can be used up to 140°F (60°C) and CPVC, with greater abrasion resistance, is suitable for temperatures up to 210°F (100°C). PVC and CPVC can be solvent-bonded together to attain the best attributes of each resin in a single pump.

Polypropylene (PP) has excellent corrosion resistance and is used in hydrocarbon service up to 185°F (85°C). It is not suitable for strong acids or chlorinated hydrocarbons. The material can be ultrasonic, vibration, and spin welded in assembly.

PVDF (Kynar) is very corrosion- and abrasive-resistant and suitable for temperatures up to 300°F (150°C). It is also relatively expensive.

PTFE (Teflon) is extremely corrosion resistant, but its low physical properties require it to have a metal reinforcement backing to withstand high pump pressures. Table 4 is a partial list of thermoplastics used for pump parts.

Thermosets Vinyl esters and epoxies are the strongest of the thermoset composites and usually do not require external metal reinforcement. Vinyl esters are resistant to corrosion, whereas the epoxy composites are resistant to solvents. Table 5 is a list of thermosets used for pump parts.

Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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