Abstract: A rising stem valve comprising a valve body, a two part valve stem and a stem guide washer. The valve body has a valve seat in a passage between an inlet and outlet port. The two part valve stem comprising a rotating stem and a non-rotating stem and the rotating stem has a threaded bore receiving a threaded end of the non-rotating stem. The non-rotating stem has a non-circular cross section external of the threaded bore and is adapted to carry a closure head to the valve seat. The stem guide washer has a bore positioned in mating relationship with the noncircular cross section of the non-rotating stem, whereby the stem guide washer prevents the stem from rotating when the upper stem is rotated.

Abstract: A high temperature and high pressure consistometer comprises a cylindrical pressure vessel having an integral bottom and a cover for said pressure vessel. A nonmagnetic canister extends downwardly from said bottom and is sealed therein. A driven magnet assembly is journaled in said canister. A drive shaft is connected to said driven magnet assembly extending into said vessel. A nonmagnetic canister extends upwardly from the cover and is sealed therein. A driving magnet assembly is journaled in said canister. A shaft connected to said driving magnet assembly extends downwardly into said vessel. A driven magnet assembly is mounted for rotation on the exterior of the downwardly extending canister and a driven magnet assembly is mounted for rotation on the exterior of the upwardly extending canister. A sample cup is connected to the upwardly extending drive shaft and a paddle is connected to the downwardly extending shaft.