Chemically Resistant Connectors for Extreme Environments
Download the printer-friendly Chemically-Resistant Connectors for Extreme Environments Application Note
Sulfuric acid corrosion in many materials is dependent upon the acid concentration. Many materials that will not corrode when in contact with 98% concentrations of sulfuric acid may suffer significant corrosion at lower concentrations. Stainless steels are one of the material groups that can withstand very high concentrations of sulfuric acid (93% - 98% concentrations) but suffer significant corrosion at lower concentrations.
pictured above - stainless steel sensor body showing the effects of sulfuric acid corrosion
pictured above - remnants of a CTC A2A connector where the polycarbonate has completely disintegrated and the stainless locking ring has been seriously eroded due to the sulfuric acid
For situations requiring exposure to lower concentrations of sulfuric acid, CTC has developed PPS connectors with no exposed metal.
PPS connectors, like CTC's A2S and A3S, have an insert, backshell body, and locking ring all made from polyphenylene sulfide.
pictured above - A2S Connector - MIL-style, 2 socket connector, PPS material, no exposed metal, 392°F
pictured above - A3S Connector - MIL-style, 3 socket connector, PPS material, no exposed metal, 392°F
What are the Benefits of Polyphenylene Sulfide?
Polyphenylene sulfide is a high-performance thermoplastic material that exhibits extreme solvent resistance up to 200°C (392°F). The actual service temperature of PPS is up to 218°C (424°F). The inner sealing O-ring of the connector is made of Viton™, another acid-resistant polymer that displays excellent flexibility at higher temperatures.
PPS was selected for this application because it offers the broadest resistance to chemicals of any available advanced engineering plastic, including bases and acids, and also offers inertness to steam and hydrocarbon-based solvents.
A very low coefficient of linear thermal expansion makes PPS products ideally suited for the machine components required for CTC connectors. In addition, PPS products exhibit excellent electrical characteristics that are inherently flame retardant, which makes them ideal for use in harsh industrial environments.
