A high-performance thermoplastics, for overmolding the steel core of a cone valve, has replaced a fluoropolymer to withstanding continuous operating temperatures of 120 deg C.

Italy-based Fluorten chose Victrex PEEK, a high-performance thermoplastics, for overmolding the steel core of a cone valve used to process tomato paste. When compared to the fluoropolymer it replaced, Victrex PEEK not only extends the life of the valves, it also results in significant cost savings due to reduced downtime. During processing, the tomato paste is forced through a system of pipes and cone valves to obtain the right quality and consistency.

Because the valves are in contact with the paste, the valve material must be capable of withstanding continuous operating temperatures of 120 deg C (248 deg F) and have good non-stick properties.

It must also exhibit superior surface hardness due to the high processing rates and good adhesion to the steel core.

Victrex PEEK has a glass transition temperature of 143 degC (289 deg F) and can withstand continuous service temperatures close to the melting point of 340 deg C (644 deg F).

'The combination of thermal properties together with low wear properties and excellent adhesion of the polymer during overmolding were the major reasons Fluorten chose Victrex PEEK,' says Christine Karas, General Manager, Americas.

'The fact that Victrex PEEK is FDA approved for contact with foodstuffs and has excellent chemical and hot steam resistance were also a factor.' Victrex USA, a division of Victrex plc, is the sole manufacturer and supplier of PEEK polymer worldwide.