Background
Pentair delivers solutions for moving and cleaning water in home and commercial applications. Their IntelliChlor® Plus & LT Salt Chlorine Generators manage chlorine generation for swimming pools, and were facing installation issues in their first generation of the product. The height from Input / Output (I/O) ports to the underside of the product was too big, resulting in interference with the ground in retrofit installations. Pentair was forced to halt production of this product until the problem was solved.
Challenges
Porticos engineers were asked to work with a sense of urgency to help solve the problem and re-start production. The redesign for ground clearance was performed by Porticos under a number of design restrictions that had to be met for the project to be considered successful:
- No changes were allowed to the overall length and I/O port style to ensure backward compatibility to piping in existing installations.
- Newly designed parts had to be compatible with existing mating components, to minimize impact to the rest of the design and supply chain.
- Under the operating water pressure and mating part loads, the numerous o-rings in the design must still form reliable seals. Also, the structural integrity of the product had to be maintained by keeping induced stresses in the components under acceptable levels.
- Water flow through the new design must not introduce unacceptably large pressure drops.
Several solutions were proposed with pro’s and con’s. The selected concept was a two pronged approach in which the ports are lowered with respect to the rest of the product and a bolt flange was redesigned to reduce material on the side facing the ground. This was accomplished by redesigning the cell front and cell rear housings.
FEA simulation on the selected solution revealed high stresses in the redesigned bolt flange and were addressed by incorporating gussets and fillet radii. The simulation also confirmed that deflection in o-ring glands was on par with the existing design, which was known to seal well. 3d printed prototypes were fabricated and confirmed good fits to mating components.
Pentair tested the design one step further by having updated design cell housings machined from plastic, running pressurized water through the product, and measuring flow and pressure drop. This prototype was also put through life cycle testing that showed favorable results. All of the above tests and FEA simulations gave the team enough confidence in the structural integrity, sealing ability, and hydraulic performance to purchase mold tooling for the new cell housings.
Outcomes
The changes to the IntelliChlor product achieved the installation improvements while remaining within the existing specifications for production and delivering the necessary features. Pentair was very happy with the project, noting that the team was able to “get to work on the design issues very quickly,” turning around a solution to their installation concerns in a timely manner. The IntelliChlor® Plus & LT Salt Chlorine Generators remain a core product for the Pentair Pool line of products.
