Abstract: A stream selector for a process analyzer. The stream selector includes a valve module having two block valves and a bleed valve. In a first mode, the block valves are closed and the bleed valve is open. In a second mode, the block valves are open and the bleed valve is closed. In a third mode, all of the valves are open, thus ensuring that the module is completely purged. A stream-selection valve manifold is made by joining two or more valve modules side by side to form a common outlet and a common passageway, thus ensuring that the manifold is completely purged. The stream selector also provides a single block-and-bleed valve module having a disposal passageway which establishes fluid communication between a vent compartment and an external area suitable for the safe disposal of sample fluids and compressed gas contained in the valve module.

Abstract: A stream selector for a process analyzer. The stream selector includes a valve module having two block valves and a bleed valve. In a first mode, the block valves are closed and the bleed valve is open. In a second mode, the block valves are open and the bleed valve is closed. In a third mode, all of the valves are open, thus ensuring that the module is completely purged. A stream-selection valve manifold is made by joining two or more valve modules side by side to form a common outlet and a common passageway, thus ensuring that the manifold is completely purged. The stream selector also provides a single block-and-bleed valve module having a disposal passageway which establishes fluid communication between a vent compartment and an external area suitable for the safe disposal of sample fluids and compressed gas contained in the valve module.

Abstract: A stream selector for a process analyzer. The stream selector includes a valve module having two block valves and a bleed valve. In a first mode, the block valves are closed and the bleed valve is open. In a second mode, the block valves are open and the bleed valve is closed. In a third mode, all of the valves are open, thus ensuring that the module is completely purged. A stream-selection valve manifold is made by joining two or more valve modules side by side to form a common outlet and a common passageway, thus ensuring that the manifold is completely purged. The stream selector also provides a single block-and-bleed valve module having a disposal passageway which establishes fluid communication between a vent compartment and an external area suitable for the safe disposal of sample fluids and compressed gas contained in the valve module.

Abstract: A packing system for the operating stem of rotary valves includes first and second packing assemblies engaged with the stem at axially spaced locations. The first assembly is adjustably compressed into sealing engagement with the stem by a first packing nut which carries both the second packing assembly and a second packing nut for adjustably compressing the second packing assembly into sealing engagement with the stem independently of the first packing assembly. The space between the first and second packing assemblies provides a sealed chamber to allow detecting any leakage taking place from the valve chamber through the first stem packing assembly.

Abstract: A plug-type, rising stem needle or shut-off valve for controlling fluid flow comprises a valve housing forming a valve chamber with inlet and outlet ports connecting therewith. A bonnet member with a cylindrical passage joins with the valve chamber and opens to the exterior of the valve. A plug valve element is mounted in the chamber and adapted to be moved by an operating stem axially movable within the cylindrical passage. The stem includes a radially extending guide flange. For sealing about the operating stem and limiting the axial outwardly movement of the stem there is an assembly which includes a wall surface that defines a conical chamber at the outer end of the cylindrical passage. The conical chamber tapers from a large diameter at the axial outer end to a smaller diameter at the axial inner end. At the axial inner end of the conical chamber is a cylindrical counterbore carrying a stop ring which forms a radial shoulder for engaging the flange on the stem at a predetermined outer limit position.

Abstract: An elastomeric sleeve is placed under axial compression in a pinch valve assembly. The axial compression of the sleeve eliminates any crevices with end members that engage opposed end walls of the valve body. Further, axial compression extends cycle life of the valve by maintaining the sleeve in a non-tensile relationship. Mechanical gripping of enlarged flanges defined at opposed ends of the sleeve is also enhanced through axial compression of the sleeve. A positive, visual indication of valve open and closed positions is provided by an indicator stem extending outwardly from an actuator body. In an alternate embodiment, the flanges are reinforced. Additionally, a casting member is interposed between the valve body and sleeve for ease of replacement and maintenance. In still another embodiment, a vent opening in the valve body eliminates pneumatic closure forces on the elastomeric sleeve that can arise when the pinch valve is heated.

Abstract: An elastomeric sleeve is placed under axial compression in a pinch valve assembly. The axial compression of the sleeve eliminates any crevices with end members that engage opposed end walls of the valve body. Further, axial compression extends cycle life of the valve by maintaining the sleeve in a non-tensile relationship. Mechanical gripping of enlarged flanges defined at opposed ends of the sleeve is also enhanced through axial compression of the sleeve. A positive, visual indication of valve open and closed positions is provided by an indicator stem extending outwardly from an actuator body. In an alternate embodiment, the flanges are reinforced. Additionally, a casing member is interposed between the valve body and sleeve for ease of replacement and maintenance. In still another embodiment, a vent opening in the valve body eliminates pneumatic closure forces on the elastomeric sleeve that can arise when the pinch valve is heated.

Abstract: A new packing arrangement is provided for improved sealing and limiting potential for extrusion of one packing member relative to another. The stem packing arrangement is disclosed with particular reference to a ball valve assembly having a body housing a selectively rotatable valve member. An actuating stem extends from the body through a stem passage and the packing assembly is received in the passage around a portion of the stem. First, second, third, and fourth members progressively increase in hardness to limit extrusion of one member relative to another. A predetermined compression is also applied to the packing assembly and is independent of the actuating stem so that bearing member life is increased. The second member includes a tapered external surface that cooperates with the stem passage to provide a wedging action along the inner and outer diameter portions thereof.

Abstract: An end member of a valve body is provided with first, second, and third passages to define an integral tee fitting. Two of the passages are generally aligned for receipt in the flow path of a main processing line. The third passage extends generally perpendicular to the first and second passages and communicates with the valve chamber. The first and second passages also include threaded regions to facilitate interconnection with the main processing line.

Abstract: An elastomeric sleeve is placed under axial compression in a pinch valve assembly. The axial compression of the sleeve eliminates any crevices with end members that engage opposed end walls of the valve body. Further, axial compression extends cycle life of the valve by maintaining the sleeve in a non-tensile relationship. Mechanical gripping of enlarged flanges defined at opposed ends of the sleeve is also enhanced through axial compression of the sleeve. A positive, visual indication of valve open and closed positions is provided by an indicator stem extending outwardly from an actuator body. In an alternate embodiment, the flanges are reinforced. Additionally, a casing member is interposed between the valve body and sleeve for ease of replacement and maintenance. In still another embodiment, a vent opening in the valve body eliminates pneumatic closure forces on the elastomeric sleeve that can arise when the pinch valve is heated.

Abstract: An elastomeric sleeve is placed under axial compression in a pinch valve assembly. The axial compression of the sleeve eliminates any crevices with end members that engage opposed end walls of the valve body. Further, axial compression extends cycle life of the valve by maintaining the sleeve in a non-tensile relationship. Mechanical gripping between enlarged flanges defined at opposed ends of the sleeve is also enhanced through axial compression of the sleeve. A positive, visual indication of valve open and closed positions is provided by an indicator stem extending outwardly from an actuator body.

Abstract: A ball valve includes a ball member rotatable in a valve chamber and cooperating with a pair of opposed seal assemblies. Each seal assembly comprises a support ring and disc spring having a resilient seal member interposed therebetween. A normally occuring void in the valve chamber is filled through use of a pair of dead space rings. These dead space rings are formed of a rigid, low friction material that does not substantially increase the torque required to rotate the ball member. In addition, the rigid material prevents cold flow of the material into the fluid passageway.