Trelleborg Sealing Solutions’ Retract-A-Ball is a retractable spray ball system for tank cleaning in CIP processes.

Retract-A-Ball operates pneumatically, giving it the advantage of being fully self-draining, preventing trapping of fluid, a potential source of contamination.

Tank Cleaning Developments involved Trelleborg Sealing Solutions from the concept stage in specification of seals for Retract-A-Ball, a retractable spray ball system for tank cleaning in CIP processes.

The design of the seals presented a number of challenges, as on one side there was liquid and on the other air. Operating under pressure from both sides and at high temperatures, the seals had to withstand aggressive cleaning fluids. In addition, as Retract-A-Ball is used in food and pharmaceutical processing, compliance to relevant standards, including FDA and USP Class VI, was essential.

Extensive tests were required to meet the stringent requirements of the processing equipment manufacturers and their customers. In these, after cycles of 1,000 operations, there was no leakage and pressure was held.

The seals also continued to perform after a temperature test where the units were heated up to 140°C (284°F) for 24 hours.

The final sealing configuration in the Retract-A-Ball consists of a number of seals of various types and materials dependent on their position and function. These are:

* Specially designed spring energised Turcon PTFE based lip seals.
* O-Rings in EPDM and Isolast® perfluoroelastomer to ensure chemical compatibility.
* An O-Ring fitted on the neck of the ball treated with an FDA compliant PTFE coating to improve friction, enhancing movement in and out of the housing.

All the proprietary materials and the coating specified are specifically engineered to meet the needs of the processing industry, including compliance to FDA and USP Class VI standards.

Retract-A-Ball