Abstract: A valve to control fluid of high volume and pressure comprising a continuously balanced hollow plunger disposed within an annularly enlarged chamber that controls fluid flow by moving radial slots and ports in its peripheral wall back and forth across seals, the plunger being continuously balanced in any position by a double-rodded piston assembly comprising a piston, a ported operator rod and actuator rod, and a balance chamber within a sealed piston cylinder tube that allows the line media to flow through, out of, and around the plunger, through the operator rod and through and out of the actuator rod and into the balance chamber creating a complete continuous balancing effect on the plunger in any position, and operator means are only required to overcome seal friction and path resistance to move the plunger to selected position.

Abstract: A valve construction which may be used to control the flow of any desired fluid in any desired valving action and which provides an interchangeable and removable activating means and an interchangeable and removable valve cartridge assembly of the lap spool, packed spool, proportional flow or any other version. The valve comprises a removable and interchangeable activating means, a removable and interchangeable cap assembly, a novel housing adapted to accept a removable and interchangeable valve cartridge assembly of the lap spool, packed spool, proportional flow, or any other version, and a removable and interchangeable valve cartridge assembly of the lap spool, packed spool, proportional flow, or any other version comprised of a plunger and separator means.