WO2005026595A1

WO2005026595A1 - Blind flange valve

Info

Publication number: WO2005026595A1
Application number: PCT/NO2004/000254
Authority: WO
Inventors: Runar M. Johansen; Erling Olsen
Original assignee: Treade As
Priority date: 2003-08-29
Filing date: 2004-08-27
Publication date: 2005-03-24
Also published as: NO20033837D0

Abstract

A blind flange valve (1) including a valve housing (2), a valve element arranged within the valve housing (2) and means (3) for activating the valve element is disclosed. The valve element is made up by two valve discs (4) having respective sealing surfaces facing away from each other, which sealing surfaces are designed for sealing engagement with corresponding sealing surfaces formed within the valve housing (2). The means (3) for activation of the valve element comprises inclined surfaces (3e, 3g) that are designed to co-act with corresponding inclined surfaces (4e, 4g) arranged on the sides of the respective valve discs (4) facing each other. The valve discs (4) are arranged to be able to move back and forth within the valve housing (2).

Description

Blind Flange Valve

The present invention relates to a blind flange valve comprising a valve housing, a valve element arranged within the valve housing, means for activating the valve element, said valve element being made up by two valve discs having respective sealing surfaces facing away from each other, which sealing surfaces are designed for sealing engagement with corresponding sealing surfaces formed within the valve housing.

Blind flange valves are typically used on pipe lines to be able to shut off a fluid flow through the pipe line. Typical fields of use are on board chemical tankers, product tankers, supply ships and drilling rigs. They can also be used on land based facilities, in particular within the process industries like refineries, terminals and chemical facilities. They will often be designed into the piping and are installed during construction of the facility/vessel. Post installation is definitely also possible. They are designed for liquids, petroleum products, solvents, chemicals, gases, steam and water. When fluid flow takes place the valve element is not present within the valve housing.

More precisely are blind flange valves used at places where the valve is to be kept open or shut over a long period of time between each time it is to be operated. Other kind of valves, like for example a butterfly valve, will be subject to sticking due to inter alia deposits and corrosion after having been in the same position fore a long time. A blind flange valve is substantially more reliable in this respect since direct access to the valve element is possible, even though it is more elaborate to operate. When a blind flange valve is to be operated, the fluid flow through the blind flange valve firstly needs to be stopped in that a valve being operable from the outside, for example a butterfly valve, is shut off. Thereafter the housing of the blind flange valve can be opened and the valve body installed or withdrawn. Then the butterfly valve can be reopened.

A continuous requirement to improve the sealing ability of the valve is present so that it can be kept shut over longer periods of time without leakages.

One object with the present invention is also to provide a valve variant that is able to park the valve body within the valve housing while full flow takes place through the valve. This means that the need to partly disassemble the valve, i.e. remove the valve cover to install or take out the valve body, ceases when the valve is to be shut or reopened.

According to the present invention a blind flange valve of the introductory mentioned type is provided, which valve is distinguished in that the means for activation of the valve element comprises inclined surfaces that are designed to co-act with corresponding inclined surfaces arranged on the sides of the respective valve discs facing each other, which valve discs are arranged to be able to move toward and away from each other within the valve housing.

Conveniently the activating means comprises a spindle having a treaded portion which is in mesh with a treaded portion in a part that is in connection with the valve housing.

Together the inclined surfaces of the activating means preferably form a wedge means. Correspondingly do the inclined surfaces on the valve discs together preferably form a V-shape.

In one variant of the blind flange valve the valve housing has an enlargement in the form of a cavity for receipt of and parking of the valve element when the blind flange valve is in through flowing operating modus.

In this variant of the blind flange valve the activating means comprises an extended valve spindle received within a further extension of the valve housing, a so-called spindle housing.

Other and further objects, features and advantages will appear from the following description of two for the time being preferred embodiments of the invention, which are given for the purpose of description, without thereby being limiting, and given in context with the appended drawings where: Fig. 1 shows a longitudinal cross section of a blind flange valve according to a first embodiment of the present invention,

Fig. 2 shows a transversal cross section along line A-A in figure 1, Fig. 3 shows a partial sectioned front view through the valve according to figure 1, Fig. 4 shows a longitudinal cross section of a blind flange valve according to a second embodiment of the present invention,

Fig. 5 shows a partial sectioned front view through the valve according to figure 4, Fig. 6 shows in perspective view and in closer detail the lower end of the valve spindle, Fig. 7 shows in perspective view and in closer detail a valve disc having means for engagement with the lower end of the valve spindle shown in figure 6, and

Fig. 8 shows the blind flange valve according to figure 4 and 5 with the parts apart from each other.

Reference is firstly made to figure 1-3 for a general description of the structure of a blind flange valve 1. The blind flange valve 1 comprises a valve housing 2, a valve spindle 3 occupied within the valve housing 2, two valve elements 4 in the form of discs and a cover 5 that enable access to the inside of the valve. The valve housing 2 is provided with a bolt circle C corresponding to the bolt circle of standard flanges of a pipe line (not shown), between which the blind flange valve 1 typically is mounted. The valve housing 2 also has a bottom plug 14 for possible drainage of the housing.

The cover 5 is kept in place by two beams 6 extending transversal to the cover 5. Preferably is a sealing means, a gasket, a sealant or similar provided between the cover 5 and the valve housing 2. Each beam 6 has an aperture in each end. Four pin bolts 7 are secured to the top surface 2a of the valve housing and extend upwardly through respective apertures in the beams 6. The cover 5 can be tightened by means of respective nuts 8 mounted to the pin bolts 7. In one embodiment one of the apertures in the beam 6 can open outwardly to the side so that the beam 6 not necessarily need to be disassembled, but that it is sufficient to loosen the nuts 8 and then swing the beam 6 to the side to be able to take off the cover 5. By removing the cover 5 accesses to the valve spindle 3 is obtained. The spindle 3 has an organ 3a in its upper end, like a square or hexagon, for engagement by a tool (not shown) for rotation of the organ 3 a. Below the organ 3 a the valve spindle 3 includes a threaded portion 3b, a smooth portion 3c and an activating element 3d in the lower end thereof. The organ 3 a has internal threads that mesh with the threaded portion 3b of the valve spindle 3.

The organ 3 a is kept axial stationary to an internal partition wall 9 that can be secured to the valve housing 2 by means of clamping elements and bolt connections 11. By rotation of the organ 3a by a tool the valve spindle 3 including the activating element 3d will be guided up or down according to the sense of rotation.

The activating element 3d is again in sliding engagement with the two valve elements 4. More precisely, each valve element 4 has on that side facing toward the activating element 3d an element 4d having grooves for engagement with corresponding elements on the activating element 3d. A more detailed description of these will be given in connection with figure 6 and 7.

By this type of blind flange valve 1 the entire unit including the valve discs 4, the valve spindle 3 and the partition wall 9 will be removed from the valve housing when free flow takes place trough the valve. When the need to shut off the flow trough the valve occurs, the flow firstly needs to be shut off at a different location upstream of the valve 1. The cover 5 is then removed. Subsequently the valve spindle 3 including the mounted valve discs 4 can be lowered into the valve housing 2 until they bottom against the housing. The valve spindle 3 is mounted to the valve housing 2 by means of the partition wall 9, the clamping elements 10 and the bolt connections 11. Rotation of the organ 3a provides axial motion, i.e. in the flow direction, of the valve discs 4 until engagement and sealing against seats in the valve housing 2.

Reference is now made to figure 4 and 5 for description of a second embodiment of a blind flange valve 1 '. Parts that are similar in the two embodiments have the same reference numbers, while parts that are not the same, but equivalent to, have an apostrophe added. The blind flange valve 1 ' comprises a valve housing 2', a valve spindle 3' occupied within the valve housing 2', two valve elements 4 in the form of discs and an upper valve housing 5' that is bolted to the lower valve housing 2'. The valve housing 2' is, as previously, provided with a bolt circle C corresponding to the bolt circle of standard flanges of a pipe line (not shown), between which the blind flange valve 1' typically is mounted.

The main difference between this embodiment and the first one described, is that the valve elements 4 can be elevated from the flow opening O of the valve and be parked within the upper valve housing 5 ' . Thus the need for disassembly of the valve for installing or removing the valve elements 4 is avoided.

To enable this, the upper valve housing 5' is designed with a cavity 5a' sufficiently large to receive the valve elements 4 and in such a way that they are completely out of the flow opening O of the valve 1 '. hi addition, the upper valve housing 5' has in the upper extension thereof, a spindle housing 12 that encloses a long threaded portion 3b' on the valve spindle 3'. On top of the spindle housing 12 an organ 3 a' is rotatably mounted that can be operated by a wheel 13 or other suitable tool for rotation thereof. By rotation of the organ 3a' the valve spindle 3' including the activating element 3d will be guided up or down according to sense of rotation. The long threaded portion 3b' provides, in addition to operation of the activating element 3d, the possibility to elevate and lower the valve element 4 up into/down from the cavity 5 a'.

Both the described blind flange valves 1, 1' use similar type activating element 3d on the lower end of the valve spindle 3, 3' and the element 3d is shown in closer detail in figure 6. They also use the same type of valve discs 4 that are shown in closer detail in figure 7.

The activating element 3d includes respective inclined base surfaces 3e, which together form a wedge shape, which clearly appears from fig. 1 and 4. Two substantially L- shaped profiles project out from each base surface 3e. Between said profiles 3f and the base surface 3e a groove is formed for receiving and guiding of an element 4d on the back side of the valve element 4. Each L-formed profile 3f has an internal surface 3g extending substantially parallel to the base surface 3e. The element 4d has correspondingly an inclined base surface 4e that is designed to cooperate with the base surface 3e. The element 4d has also a substantially T- formed profile 4f, which between itself and said valve element 4 forms a groove with internal inclined surface 4g that extend substantially parallel to the base surface 4e. The inclined surface 4g is designed to cooperate with the inclined surface 3g.

As it will be understood, each valve element 4 is slidable mounted to the activating element 3d in that the T-profile 4f of the element 4d is inserted between the L-profiles 3f of the activating element and is axially limited downwardly by a stopper 15 and an end screw 16, as shown in figure 1 and 4.

By turning the organ 3 a of the embodiment according to figure 1-3 clockwise, this will displace the activating element 3d downwardly and thus bring the inclined base surfaces 3e to engagement against the inclined base surfaces 4e of the element 4d. Thus the motion downwardly of the valve spindle 3 is converted to axial motion of the valve elements 4 until sealing against the housing 2. In this way the valve elements 4 can be firmly tightened against the valve housing 2 by only turning the organ 3 a by a tool.

By turning the organ 3a in the opposite direction, i.e. counterclockwise, this will displace the activating element 3d upwardly and thus immediately bring the inclined internal surfaces 3g to abutment against corresponding inclined surfaces 4g on the element 4d. By further displacement upwardly the inclined surfaces 3g on the activating element 3d cause that the valve element 4 is moving axially away from the sealing surface of housing due to the co-acting inclined surface 4g on the element 4d.

Fig. 8 shows the blind flange valve 1 ' according to fig. 4 and 5 with the parts apart to be able to view clearly the components thereof. As shown the valve 1 ' has also a gland 17 retaining a seal 18 acting against the smooth portion 3c' of the valve spindle 3'. It is also shown two replaceable sealing rings 19 that can be used between the valve elements 4 and the valve housing 2. In addition it is illustrated misc. pin bolts and nuts to keep the respective parts together.

Claims

P a t e n t C l a i m s

1.

A blind flange valve (1) comprising a valve housing (2), a valve element arranged within the valve housing (2), means (3) for activating the valve element, which valve element is made up by two valve discs (4) having respective sealing surfaces facing away from each other, which sealing surfaces are designed for sealing engagement with corresponding sealing surfaces formed within the valve housing (2), characterized in that the means (3) for activation of the valve element comprises inclined surfaces (3e, 3g) that are designed to co-act with corresponding inclined surfaces (4e, 4g) arranged on the sides of the respective valve discs (4) facing each other, which valve discs (4) are arranged to be able to move toward and away from each other within the valve housing (2).

2.

The blind flange valve according to claim 1, characterized in that the means for activating the valve element comprises a spindle (3) having a threaded portion (3b) which is in mesh with a threaded portion in an organ (3 a) that is rotatably mounted to the valve housing (2).

3.

The blind flange valve according to claim 1, characterized in that the inclined surfaces

(3e) on the means for activating the valve element together form wedge means.

4.

The blind flange valve according to claim 1, characterized in that the inclined surfaces (4e) on the valve discs (4) together form a V-shape.

5. The blind flange valve according to claim 1, characterized in that the valve housing (2') has an enlargement in the form of a cavity (5a') for receipt and parking of the valve discs (4) when the blind flange valve (1 ') is in through flow modus.

6.

The blind flange valve according to claim 5, characterized in that the means for activating the valve element comprises an extended valve spindle (3 ') received within a further extension (12) of the valve housing (2').