Mother's Day is a celebration honoring mothers and celebrating motherhood, maternal bonds and the influence of mothers in society. It is celebrated on various days in many parts of the world, yet most commonly in March, April, or May.
Coils, rings, and corrugated ribbon are the common forms of packing used in valves. The form of packing to be used in repacking a particular valve will depend on the valve size, application, and type. Packing materials will be discussed in more detail later in this chapter.
Piston & Ball Check Valves. Piston and ball check valves, like all check valves, are used to prevent back flow in the line. Standard valve design has no spring in order to minimize cracking pressure and pressure drop, it will only function properly when installed in a horizontal line.