Water lines on the surface of the rubber sleeve of butterfly valve refer to visible patterns or grooves (often in the form of ribs or channels) that are sometimes molded into the rubber. These water lines could serve a few purposes:
Improved Sealing Performance: The grooves or channels can help direct water away from certain areas, potentially improving the seal by helping to distribute the pressure more evenly along the rubber sleeve. This could be useful in applications where pressure differentials might lead to leaks.
Water Flow Management: The lines can be designed to improve the flow characteristics of water or other fluids in certain applications, which can help reduce turbulence and improve overall performance in some systems.
Durability: In some cases, the water lines could improve the durability of the rubber by reducing localized stress concentrations, thus preventing premature wear and tear.
