A stuffing box for sealing a top opening of a vertical pump, including: a housing with a vertical tube for rotatably disposing a shaft of the vertical pump, an annular bearing that: divides the vertical tube in a lower half and an upper half, and fills an annular space between an inner wall of the vertical tube and the shaft, such that as less fluid as possible passes from the lower half through the annular bearing to the upper half, an outlet pipe for discharging the fluid passing through the annular bearing.

A valve packing having independently loaded packing rings is disclosed. A packing assembly for a fluid valve includes a first packing ring, a first follower to be disposed at least partially within a bore of a bonnet of the fluid valve to apply a first load to the first packing ring, a second packing ring sized to fit within a bore of the first follower, and a second follower to be disposed at least partially within the bore of the first follower to apply a second load to the second packing ring within the bore of the first follower.

A stuffing box for sealing a top opening of a vertical pump, including: a housing with a vertical tube for rotatably disposing a shaft of the vertical pump, an annular bearing that: divides the vertical tube in a lower half and an upper half, and fills an annular space between an inner wall of the vertical tube and the shaft, such that as less fluid as possible passes from the lower half through the annular bearing to the upper half, an outlet pipe for discharging the fluid passing through the annular bearing.

The disclosure concerns a seal, in particular a rod seal for sealing an axially movable rod in a guide cylinder, in particular a piston seal for a pneumatically, electrically or hydraulically driven coating agent pump for pumping coating agent, having an annular sealing element for sealingly resting on a circumferential surface of an axially movable rod, and having at least one elastic annular pretensioning element, the annular pretensioning element surrounding the annular sealing element radially on the outside and pretensioning it radially to the inside. The disclosure provides an annular seal base body which externally surrounds and holds the sealing element and the pretensioning element. In addition, the disclosure also comprises an inverted variant in which the seal is arranged in an annular groove in a lateral surface of a piston and lies sealingly against the cylinder running surface.

A pressure-tight stein cylinder seal and a self-energizing stein shoulder seal matching the stein cylinder seal that both use an equilaterally triangular soft ring as their sealing element, wherein their designing rules are first, by means of wedging function of a hard gland coaxial with the stein cylinder, to convert their original axial tightening force 2f respectively into a radial compression force 4f/√3 of their soft ring 04 on the stein 02 cylinder and another radial compression force 2f of their soft ring 06 on the stein 02 shoulder and ensure that the two soft rings are so compressed from a great room to a small room as to be able to pass a pressure or stress exactly to each different direction, then to cut off their off-stein corners to give their cavities an opening or give each soft ring an axial compressing allowance, and last, by means of anti-extrusion metallic C-rings without axial resistance, to close each opening to provide a full support for the sealing deformation of their soft rings compressed in their cavities.

A seal assembly for a valve stem comprises an external seal placed on a valve stem facing an external environment; an internal seal placed on the valve stem facing a process environment; the external and internal seals define a chamber for the containment of barrier fluid; the chamber has an inlet configured to be placed into fluid communication with a source of barrier fluid; a detector of the amount of barrier fluid; a pressurizer device for providing the chamber with a positive pressure with respect to the process environment; the pressurizer device is configured to be installed coaxially with the valve stem.

A valve packing having independently loaded packing rings is disclosed. A packing assembly for a fluid valve includes a first packing ring, a first follower to be disposed at least partially within a bore of a bonnet of the fluid valve to apply a first load to the first packing ring, a second packing ring sized to fit within a bore of the first follower, and a second follower to be disposed at least partially within the bore of the first follower to apply a second load to the second packing ring within the bore of the first follower.

A pressure-tight stem cylinder seal and a self-energizing stem shoulder seal matching the stem cylinder seal that both use an equilaterally triangular soft ring as their sealing element, wherein their designing rules are first, by means of wedging function of a hard gland coaxial with the stem cylinder, to convert their original axial tightening force 2f respectively into a radial compression force 4f/√3 of their soft ring 04 on the stem 02 cylinder and another radial compression force 2f of their soft ring 06 on the stem 02 shoulder and ensure that the two soft rings are so compressed from a great room to a small room as to be able to pass a pressure or stress exactly to each different direction, then to cut off their off-stem corners to give their cavities an opening or give each soft ring an axial compressing allowance, and last, by means of anti-extrusion metallic C-rings without axial resistance, to close each opening to provide a full support for the sealing deformation of their soft rings compressed in their cavities.

One or more packing systems and/or methods of manufacture are disclosed for a valve seal with lowered emissions while being complaint with fire standards. The packing system may have alternating mid-layers, a top layer, a bottom layer, and a first end cap and a second end cap. The layers can be formed of a flexible graphite-based material and/or a perfluoroalkoxy alkane (PFA) material. The layers may be bonded together and expand under compression to form a seal between a valve stem and a stuffing box.

A main object of the present invention is to disclose a piston rod sealing unit that solves the problems that have been mentioned from the prior art disclosures. The invention is a piston rod sealing system (0) with a sealing unit (9), for preventing leakage, of gas from a high-pressure chamber (4) to a low-pressure volume (6), and preventing leakage of a lubricant from said low-pressure volume (6) to said high-pressure chamber (4), along a piston rod (1) extending through said chambers (4, 6) said sealing unit (9) comprising, —a deformable gland (10,21,26) arranged for being pressed against said piston rod (1) by one or more compressing elements (15, 22, 27), —a lubricant (F) between the piston rod (1) and the gland (10, 21, 26), said sealing unit (9) arranged between, —a support structure (8) in the low-pressure volume (6) with a plane sliding surface (8a) facing towards said sealing unit (9), —and a wall (7) of said high-pressure chamber (4), —a plane seal (16) constituting a seal between the sealing unit (9) and said wall (7), said plane seal (16) arranged in a groove (13b, 24a, 26e) in said sealing unit (9), said groove open towards said wall (7), or said plane seal (16) arranged in a groove in the wall (7), said groove open towards said sealing unit (9) wherein, —said sealing unit (9) having a surface area towards said wall (7) between said piston rod (1) and said plane seal (16) smaller than the sliding area between said sealing unit (9, 12b, 25a, 28a) and the plane sliding surface (8a), and —said sealing unit (9) being supported by said plane sliding surface (8a) on the low-pressure side, and said sealing unit (9) being in sliding contact with said wall (7) surface (7a), the length (L′) of said sealing unit (9) is less than the length (L) between the base structure (8) and the wall (7) allowing transverse movement of the sealing unit (9) along the sliding surfaces (7a, 8a).