DK201770316A1 - Shut-off valve and method for cleaning the shut-off valve - Google Patents

Abstract

A method for cleaning shut-off valve (1) in a process plant (2) for coatings after use, in which the shut-off valve (1) in its mounted state in the process plant (2) goes through a number of cleaning steps comprising rinsing with rinse aid, heating with hot steam and drying out under low pressure. In accordance with the invention, at least a rinse aid rinse with the shut-off valve (1) is closed.

Description

( ¹⁹ ) DENMARK (10)

DK 2017 70316 A1

(12)

PATENT APPLICATION

Patent and Trademark Office (51) Int.CI: F16K1 / 44 (2006.01) F16K1 / 00 (2006.01) (21) Application number: PA 2017 70316 (22) Filing date: 2017-05-08 (24) Running day: 2017-05 -08 (41) Aim. available: 2018-11-09 (43) Publication date: 2018-12-14 (71) Applicant:

Limitech Finance APS, Fristrupvej 162-164, 9440 Aabybro, Denmark (72) Inventor:

Thomas Mogensen, Østerled 16.9490 Pandrup, Denmark (74) Plenipotentiary:

PATENT NORD ApS, Kjeldgaardsparken 31,9300 Sæby, Denmark (54) Title: Shut-off valve and procedure for cleaning shut-off valve (56) Published publications:

WO 2016/091204 A1

JP 2017/057561 A

CN 2017/72125 U (57) Summary:

A method of cleaning shut-off valve (1) in a process plant (2) for coatings after use, in which the shut-off valve (1) in its mounted state in the process plant (2) goes through a number of cleaning steps comprising rinsing with rinse aid, heating with hot steam and drying out under low pressure. According to the invention, at least one rinse with rinse aid is carried out with the shut-off valve (1) closed.

To be continued...

DK 2017 70316 A1

DK 2017 70316 A1

Shut-off valve and method for cleaning the shut-off valve.

The invention relates to a method for cleaning a shut-off valve for coatings after use, in which the shut-off valve in its mounted state in a process plant goes through a number of cleaning steps.

Such a process is known as CIP cleaning, which is an abbreviation of Cleaning In Place, since the shut-off valve remains mounted during the cleaning process. This type of cleaning process typically involves flushing the valve in its open state with a cleaning agent.

According to the invention, a number of cleaning steps are carried out, the cleaning steps comprising rinsing with rinse aid, heating with hot steam and low pressure drying, where at least rinsing with rinse aid is done with the shut-off valve in the closed state. This ensures, in particular, that the closing surface of the shut-off valve is properly cleaned, while the cleaning fluid does not penetrate through the shut-off valve and further into a processing plant.

According to claim 2 of the invention, a center tube conducting material to or from the shut-off valve is guided in its axial direction towards or away from a pipe flange which circumscribes the shut-off valve, in a first use situation the center pipe is advanced for packing throughout its circumference against the circumferential pipe flange and in a a second use situation intended for cleaning the shut-off valve is returned in its axial direction in a direction away from the circumferential pipe flange, thereby opening an alternative flow channel perpendicular to the longitudinal axis of the center pipe, with the shut-off valve in the first use situation:

either open and allow material to pass through the shut-off valve and through the center pipe, or ii. is closed and blocked for material transport through the shut-off valve and thus also closes the center pipe,

DK 2017 70316 A1 as the shut-off valve in the second use situation:

iii. either is open and allows material transport through the center pipe and through the alternate flow channel and through the shut-off valve, or iv. is closed so that there is only transport through the center pipe past the shut-off valve and through the alternate flow channel.

An alternate flow channel perpendicular to the longitudinal axis of the center tube is provided by the shut-off valve in the second use situation intended for cleaning, so that the cleaning liquid can come into good contact with the shut-off valve, especially when closed. But even when open, the alternate flow channel can be used for draining of cleaning fluid, which is, for example, passed through the now open shut-off valve. By this method, it is thereby ensured via the alternative flow channel that not only the surface of the shut-off valve against the center pipe, but all parts thereof including gasket surfaces can be ensured an effective cleaning and the discharge of cleaning fluid can be done safely through the alternative flow channel.

It is preferred according to claim 3 that the center tube be moved in its axial direction by establishing a pressure difference between the two sides of an annular piston axially coupled to the center tube, with the annular piston externally sealing against a cylinder which is held against the circumferential flange. This provides a safe and precise control of the position of the center pipe so that closing and opening of the alternative flow channel can always be controlled. In addition, the alternative flow channel can be completely closed as the center tube is pressed against a seat gasket in the surrounding flange and can maintain this pressure due to a pressure difference between the two sides of the piston.

The invention also relates to a shut-off valve suitable for carrying out the method according to claim 4, wherein the shut-off valve is mounted in

DK 2017 70316 A1 has a pipe flange and comprises a center pipe which can be coupled to the pipe flange, the center pipe and pipe flange thereby forming a detachable flow channel. What is special about the shut-off valve is that an alternate flow channel comprises a closable annular passage between a first end of the center tube and the tube flange. This alternative flow channel allows, at its location near the shut-off valve, that flow through the alternative flow channel may help to clean the active surfaces of the shut-off valve. When the shut-off valve is closed, flowing cleaning fluid can flow through the center pipe and strike against the closed surface of the shut-off valve and then pass out through the alternative radially oriented alternative flow channel. However, even during opening and closing of the shut-off valve, the alternate flow channel can be used to dispense cleaning fluid as the liquid sends through the shut-off valve for cleaning valve seats and other parts thereof.

As stated in claim 5, it is preferred that the center tube be mounted axially movable in a cylinder coupled to the tube flange and that a two axial side annular piston is axially fixed to and surround the center tube, forming a gasket surface against the inside of the cylinder such that a pressure difference between the piston two axial sides will move the center tube toward or away from the tube flange. This makes it possible, for example, to control the position of the center pipe with, for example, compressed air or via hydraulics, so that a cleaning cycle could possibly be established via connection of a process plant which includes the shut-off valve to a signal generator such as a computer or other control system.

As stated in claim 6, adjacent to the tube flange and surrounding the center tube, a tube piece is arranged which encircles the alternate flow channel and is secured to the cylinder, which also comprises packing means against an outside side of the center tube, so that the center tube is axially displaceable in relation to the cylinder. to the cylinder. Hereby, the flow in the alternate flow channel is obtained from the fluid pressure established on one or the other side of the annular piston.

DK 2017 70316 A1

As stated in claim 7, a seat gasket is arranged in the region between the first end of the center tube and the tube flange. It is hereby ensured that when the alternative flow channel is closed, it will be hermetically sealed from the center tube and into the alternative flow channel, and by arranging the seat pack of a suitable plastic a good abrasion resistance and sustained packing ability can be obtained.

As stated in claim 8, the shut-off valve mounted in the pipe flange is a butterfly valve I. This valve type is simple in its construction and can be used in many types of applications. In addition, it has a valve flap which, during the cleaning process, can be set longitudinally by the flow of cleaning fluid so that both sides of the valve flap can be cleaned at the same time as the valve seat is exposed to cleaning.

As stated in claim 9, the pipe piece is attached to the flange pipe via a first bolt assembly and the cylinder is coupled to the pipe flange via a second bolt joint between the cylinder and the pipe piece. Bolt joints provide easily separable elements, and at the same time, the individual parts of the shut-off valve are geometrically simple and easy to manufacture, for example via a chip-making processor.

The invention will now be explained in more detail with reference to the drawings, in which:

FIG. 1 shows a section through the shut-off valve,

FIG. 2 shows the shut-off valve from outside in 3D rendering,

FIG. 3 is a sectional and end view with the shut-off valve and the alternate flow channel both closed,

FIG. 4 is a section and end view with the shut-off valve closed but with the alternative flow channel open,

FIG. 5 is sectional and end bilge with the shut-off valve in the open state and the

DK 2017 70316 A1 alternative flow channel closed,

FIG. 6 is a sectional and end view with the shut-off valve open but with the alternative flow channel closed,

FIG. 7 is a section through a system with the shut-off valve mounted; FIG. 8 is an enlarged circular section of FIG. 7 with the cut-off valve shown in section.

For example, a shut-off valve according to the invention can be used in a plant of the type shown in FIG. 7. here, a closed mixing vessel 18 is provided with an inlet 19 at the bottom, the flow through the inlet being controlled by a shut-off valve 1 as shown in the enlarged section of FIG. 8. The shut-off valve 1 is connected via a flexible hose 20 to a container storage container 21 which, for example as shown in FIG. 7 is funnel-shaped, such that a powder material (not shown) in the container is directed by a certain pressure against the hose connection 20 to the shut-off valve 1. Pressure differences between the mixing vessel and the storage vessel and the position of the shut-off valve can now regulate the flow of powdered material to the mixing vessel 18.

Over time, in a plant of this type, coatings of the powdered material will be deposited on the inner surfaces in contact therewith, and consequently it is necessary that the plant also has means for enabling it to be cleaned at appropriate times, e.g. production to another, or when there is a risk of deposited powder rancid or otherwise decomposed and then ends in the mixing vessel.

When the shut-off valve 1, the funnel-shaped storage vessel 21 and the pipe connection 20 between the two are to be cleaned, the shut-off valve 1 is closed and an alternative flow channel 5, which goes all the way along a connecting flange for the shut-off valve 1, is opened. Hereby, a flushing agent can be added via a spray ball 22 and flow from the funnel-shaped storage container 21, through the pipe connection 20 and all the way to the closed shut-off valve 1, and from here flow radially into the alternative flow channel 5

GB 2017 70316 A1, at least the part of the shut-off valve facing away from the closed mixing vessel 18 is exposed to the rinse aid and is thereby cleaned of coatings. If the various gasket faces of the shut-off valve and the side thereof facing the mixing vessel are also desired to be cleaned, this can be done by briefly opening the valve 1.

The process here is also called CIP, which is short for the English Cleaning In Place. In this process, valves, pipes and containers are cleaned without separating these parts. In FIG. 7, the spray ball 22 is marked inside the funnel-shaped storage container 21, and this helps to clean the funnel-shaped storage container 21.

The CIP cleaning fluid is passed through the alternate flow channel 5 of the valve and via a side nozzle 23 and out through a pump 24. From here the liquid can be sent for cleaning or diverted to the recipient.

In a next step of cleaning hot steam is supplied through the alternate flow channel 5 and the steam connection 25 is also indicated. The steam flushes both the storage container 21, the hose 20 and the section between the shut-off valve 1 and the connection for the hose 20. The hot steam ensures a heating of the parts of the plant and a sterilization of the parts of the steam coming into contact.

In a final cleaning, the plant must be dried out, and this is done by closing the alternate flow channel to and in the mixing vessel 18, a certain negative pressure is established, so that all residues of steam or water are sucked out this way with the shut-off valve in this process step open. Drying air may be used. is sucked through the hopper 21 to ensure that all surfaces are completely dry. After drying, the system can be re-used.

In Figures 3 - 5, the various positions are the opening of the alternative

DK 2017 70316 A1 flow channel 5 and shut-off valve 1 allow for viewing. In FIG. 3 and 4, the shut-off valve 1 is closed and the alternative flow channel is closed in FIG. 3 and open in FIG. 4th

In FIG. 5 and 6, the shut-off valve 1 is open and in FIG. 5 shows the alternative flow channel closed by and in FIG. 6 it appears opened.

Opening and closing of the alternate flow channel 5 is accomplished by moving the center tube 3 in its axial direction with respect to the flange tube 4, so that its one end 11 is either spaced apart from the seal 15 or abuts. The center tube 3 is at its other end coupled to a flexible hose 20 or movable tube so that the movement of the center tube can be accommodated therein.

Around the center tube 3 is mounted an annular piston 6 which is internally coupled in the axial direction to the center tube, so that this piston 6 and the center tube 3 are moved as a total unit, the piston having radially exterior gasket packing against the inner surface of a cylinder. 7. The cylinder 7 is attached directly or indirectly in the axial direction to the surrounding tube flange. The piston 6 has a first axial side 8 and opposite it a second axial side, each of which is actuated via each of its connecting nozzles 25, 26 for e.g. compressed air or hydraulic oil. By controlling the pressure difference between the fluid pressure in the two connecting rods in relation to the areas of the two annular piston sides 8,9, it is possible to obtain a resultant force on the piston in the axial direction and thereby the axial position of the center tube 3 can be affected. The fluid supplied to the two cavities adjacent to one and the other side of the annular piston 6, respectively, is kept separate from the flow channel through appropriate gaskets between the center tube and inwardly directed prisoners on the cylinder 7.

When the center tube 3, as shown in FIG. 6 and FIG. 4 is offset from the seat gasket 15, the alternative flow channel 5 will be open and this

DK 2017 70316 A1 flow channel comprises, as shown, an annular area formed by a pipe piece 13 encircling the center pipe 3. The pipe piece 13 also comprises a suction nozzle 23 so that a fluid passage from the flow channel 10 and into the alternative flow channel 5 is radially relative to the center pipe. This makes it possible to send cleaning fluid through the center pipe 3 and out into the alternative flow channel with the shut-off valve closed as shown in FIG. 4 to clean the parts of the shut-off valve facing the center pipe. During such a cleaning process, the shut-off valve can be made to change position to also clean both the valve seat and parts of the valve, which otherwise in its closed state turns away from the center pipe.

It is noted that the suction nozzle 23 via a valve and a pipe connection with a cleaning pipe 27 to a pump 24 can be supplied with a suitable vacuum so that cleaning fluid can be drawn through the system. The liquid is supplied via a spray ball 22 also shown in FIG. 7 of the storage container 21. Hereby the whole system can be flushed with cleaning liquid, so that all the deposits that the powder in the tank 21 has to form on the surfaces it comes into contact with can be removed.

As seen in FIG. 1, there is a first bolt assembly 16 between an inward flange of the pipe piece 13 and the surrounding tube flange 4, and further seen in FIG. 1 shows another bolt assembly between the center pipe 3 and the pipe piece 13. Center pipe 3, pipe piece 13 and the surrounding pipe flange 13 therefore constitute a total whole and it is in this respect that the center pipe 3 is movable.

The shut-off valve 1 is shown in FIG. 1 and here is a butterfly venti I, but other types of shut-off valves may be used. The butterfly valve has a rotatable valve flap, and through a spindle 28 extended radially through an opening in the surrounding tube flange 4, the valve flap can be rotated and positioned to block the opening in the tube flange as seen in FIG. 2, FIG. 3 and FIG. 4. Alternatively, the valve flap can be rotated to release the opening which

DK 2017 70316 A1 is shown in fig. 5 and 6. Embedded in the surrounding tube flange 4, a flexible gasket 29 is provided. In the present embodiment, the tube flange is formed of two parts, one of which faces the closed mixing tank 18 and the other faces the center tube 3, where it also 5 flexible gasket 29 is embedded between the two parts of the pipe flange 4. The first bolt assembly 16 holds the two parts of the surrounding tube flange 4 together.

DK 2017 70316 A1

Numeral

Shut-off valve process plant center pipe encircling pipe flange alternate flow channel annular piston cylinder first axial side of annular piston second axial side of annular piston lockable flow channel first end of the center pipe gasket surface against the inside of the cylinder pipe piece gasket means on the outside of the center pipe socket gasket pipe storage tank spray ball suction pump pump connection nozzle to first axial side connection nozzle to second axial side cleaner pipe spindle flexible gasket

DK 2017 70316 A1

Claims (10)

patent claims A method for cleaning shut-off valve (1) for coatings after use, wherein the shut-off valve (1) in its mounted state in a process plant (2) goes through a number of cleaning steps comprising rinsing with rinse aid, hot steam heating and low pressure drying, wherein at least one rinse with rinse aid is made with the shut-off valve (1) closed. A method for cleaning shut-off valve (1) according to claim 1, wherein a center pipe (3) conducting material to or from the shut-off valve (1) is guided in its axial direction towards or away from a pipe flange (4) which circumscribes the shut-off valve (1). ), wherein the center tube (3): a. In a first use situation, the gasket is fed in its entire circumference against the circumferential pipe flange (4) and where the shut-off valve (1) here either open and allow material to pass through the shut-off valve (1) and through the center tube (3), or ii. is closed and blocked for material transport through the shut-off valve (1) and thus also closes the center pipe (3), b. In another use situation intended for cleaning the shut-off valve (1), in its axial direction, it is moved back away from the circumferential pipe flange (4), thereby opening an alternative flow channel (5) perpendicular to the longitudinal axis of the center pipe (3) and where the shut-off valve (1) ) here: either open and allow material transport through the center pipe and through the alternate flow channel (5) and through the shut-off valve (1), DK 2017 70316 A1 ii. is closed so that there is only transport through the center pipe (3) past the shut-off valve (1) and through the alternative flow channel (5). Method according to claim 1, characterized in that the center tube (3) is moved in its axial direction by establishing a pressure difference between the two sides of an annular piston (6), which is connected axially to the center tube (3), with the annular piston (6). ) externally seals against a cylinder (7) which is held against the surrounding flange (4). 4. Shut-off valve (1) mounted in a pipe flange (4) and a switchable center pipe (3) coupled to the pipe flange (3), where the center pipe (3) and pipe flange (4) thereby constitute a detachable flow channel (10) characterized by an alternative flow channel ( 5) comprises a closable annular passage between a first end of the center tube (3) and the tube flange (4). Shut-off valve according to claim 4, characterized in that the center pipe (3) is mounted axially movable in a cylinder (7) coupled to the pipe flange (4) and that an annular piston (6) with two axial sides (8,9) is axially fixed to and surrounding the center tube (3), forming a gasket surface (12) against the inside of the cylinder such that a pressure difference between the two axial sides of the piston (8,9) will move the center tube (3) toward or away from the tube flange (4). A shut-off valve according to claim 5, characterized in that a pipe piece (13) is arranged adjacent to the pipe flange (4) and the surrounding center pipe (3), which surrounds the alternative flow channel (5) and is fixed to the cylinder (7), which cylinder (7) also comprises packing means (14) towards an outside side of the center tube (3) so that the center tube (3) is axially displaceable relative to cylinder (7). DK 2017 70316 A1 Shut-off valve according to claim 6, characterized in that a seat gasket (15) is arranged in the region between the first end (11) of the center tube (3) and the tube flange (4). Shut-off valve according to claim 5, characterized in that the shut-off valve (1) mounted in the pipe flange (4) is a butterfly valve I. Shut-off valve according to claim 7, characterized in that the pipe piece (13) is 10 is secured to the flange pipe (4) via a first bolt assembly (16) and the cylinder is coupled to the pipe flange (4) via a second bolt assembly (17) between the cylinder (7) and the pipe piece (13). DK 2017 70316 A1 1.4