EP1409608B1 - De-coking tool - Google Patents

Abstract

A tool for disintegrating coke has a housing attached to a drill stem in operation, at least one nozzle for cutting and one nozzle for drilling of coke, and at least one valve for closing and opening the nozzles, wherein the tool is adapted to have two different operating states and wherein the at least one valve closes off the cutting nozzles in the drilling operating state, while the drilling nozzles are closed off by the at least one valve in the cutting operating state, and wherein the housing, the valve and the nozzles are adapted so that water may flow unhindered from the drill stem through the housing and the valve and through the nozzles not closed off by the valve, wherein, the nozzles to be closed, for each chosen operating state, are closed off by the balls of a ball valve. An arrangement for operating the valve is arranged above the nozzles.

Description

The invention relates to a tool for crushing coke.

In oil refineries, the last, otherwise unusable fraction of crude oil is converted into coke. The conversion takes place by introducing this fraction into drums that fill with coke with increasing operating time. When the maximum level of the drums is reached, the coke is cut out of the drums.

This so-called "de-coking" is usually carried out with high-pressure water jets, which crush the coke and wash out of the drums. The tool for generating these high-pressure water jets is introduced via a drill string from above into the drum. The de-coking is carried out in two sections. First, an opening is drilled through the tool in the drum from top to bottom, then the tool is returned to the top of the drum and the coke is now pressurized by high pressure jets generated by the cutting nozzles approximately perpendicular to the axis of the bore , crushed.

The tool is therefore designed for two operating conditions, firstly for drilling an opening required for moving the tool and later discharging depleted coke, and secondly for cutting the coke across the cross section of the drum. Accordingly, the boring nozzles emit high pressure water jets substantially parallel or at an acute angle to an axis formed by the boring bar and the bore created during drilling. The cutting nozzles, on the other hand, produce high pressure water jets which are oriented substantially at right angles or at a shallow angle to the axis formed by the drill rod and the opening in the drum.

The changeover between the operating states drilling and cutting must be quick and easy. The nozzles used in the tool, due to the high water pressure, wear and tear and must be replaced regularly. Accordingly, the tool must be designed so that an exchange of the nozzles can be made quickly and safely.

It is an object of the invention to provide a tool for crushing coke that is particularly easy and safe to use and maintain.

The above object is achieved with a tool having the characterizing features of claim 1. Tools for comminuting coke with a housing, which is fixed to a boring bar in the operating state, and on which or in which at least one nozzle for cutting and drilling coke and at least one valve for closing and opening the nozzles are arranged Known in the art, see for example WO-A-98/46698 . DE-A-39 41 953 and EP-A-0293972 , These tools are designed for two different operating states. The at least one valve closes the cutting nozzles in the operating state "drilling", while in the operating state "cutting" the drilling nozzles are closed by the at least one valve. The housing, the valve and the nozzles are designed with these tools so that an unhindered passage of water from the drill rod through the housing and the valve as well as the valves not closed by the valve is ensured.

Significantly simplified, the structure of such a tool is characterized in that the depending on the selected operating state to be closed nozzles are closed by the balls of a ball valve. Combinations of a ball valve for opening and closing drilling nozzles and other means for opening and closing cutting nozzles are known, but require the use of multiple components and result in a complex structure tool.

The present invention has the advantage that the number of components is reduced and that it is completely ensured that only one nozzle or a group of nozzles is closed and the other nozzle or group of nozzles is opened.

Part of the tool is a valve having a valve carrier, which is in engagement with the balls for closing the nozzles. Further associated with the valve means for guiding the balls and possibly positioning aids, by means of which the balls are held in predetermined positions. A device for actuating the valve is also associated with the valve. The valve is arranged in the housing of the tool and in operation flows through or flows through the water used for decomposing the coke.

The balls of the ball valve are guided in the valve carrier by corresponding means for guiding balls. Either means arranged on the valve support for guiding are provided. This can z. B. half shells or guide grooves or grooves or guide lugs, which are in engagement with the balls. Alternatively, however, an arrangement is possible in which the valve carrier associated balls are arranged by springs in the appropriate operating condition appropriate position. The means for guiding can thus be formed either on the valve carrier or be formed independently of it. The latter embodiment then cooperates with balls and valve carrier for guiding the balls. The means for guiding can also be multi-part, for example, a recess or groove in the valve carrier, which cooperates with a spring arrangement to guide the balls.

The balls may be formed as completely spherical bodies. However, it is also readily possible for the balls to be formed in sections only spherically, where they close an access to a nozzle in the operating state. The spherical design of this surface section ensures that the access to the respective nozzle to be closed is securely sealed against the passage of liquid. For example, a circular disk whose one side is spherically curved would fully meet the requirements of closing the nozzle. Accordingly, not completely spherical bodies in the context of the invention are referred to as "balls".

Preferably, the balls are formed as symmetrical bodies which have at least two spherical surface sections. In general, these spherical surface sections are opposite each other, for. B. as calottes, with their maximum Adjacent circumference. These symmetrical balls have the advantage that they are easy to guide on the one hand due to the symmetry of the means for guiding the balls in the valve carrier. On the other hand, they have the advantage that, if a first spherical surface section z. B. wear traces that symmetrical balls can be easily turned. Then a different dome with a second spherical surface portion may be used to seal the nozzle. Compared with the completely spherical ball, the symmetrical balls are generally preferred, because especially when tools with a small diameter are to be designed, the symmetrical balls have a diameter that is smaller relative to the diameter of the tool than completely spherical balls.

According to a first embodiment of the valve carrier is integrated into the housing such that it is part of the outer wall of the tool. According to a second embodiment, the valve carrier is mounted inside the housing. The means for guiding the balls as well as possibly the valve carrier are arranged in the housing of the tool, but do not fill it out completely in the rule. Accordingly, there are free spaces between the means for guiding the balls and the valve carrier and the housing. According to an advantageous development of the invention, these free spaces are in connection with the interior of the tool, so that the liquid flowing through the tool in the operating state can also flow through these free spaces. The advantage of this arrangement is that there is no pressure gradient between the interior and the free spaces between the housing and the valve carrier in the tool. Accordingly, the valve carrier can be designed to save material, because no pressure differences with the corresponding pressure and tensile forces must be absorbed. In addition, the avoidance of pressure differences ensures the smooth functioning of the ball valves.

A particularly preferred embodiment of the tool according to the invention has a valve carrier, in which the nozzles are arranged one above the other for cutting in two or more layers. This significantly increases the performance of the tool. The nozzles are preferably arranged offset from one another in the different layers.

The changeover from the operating state "drilling" to the other operating state "cutting" takes place manually with most known tools. The tool is withdrawn from the drum after the first operation, and a device disposed inside the tool is actuated, which, upon completion of drilling, closes the downwardly directed drilling nozzles and opens the cutting nozzles.

This device for closing one or more nozzles is actuated by means which, on the one hand, are in engagement with the closing device and, on the other hand, have a control element which can be actuated from outside the tool. This control element is always mounted below the tool in known decoking tools. Arrangements for changing over a decoking tool according to this design are robust and operationally proven. But they have the particularly serious disadvantage that the tool must be completely pulled out of the drum, and that when switching from "drilling" to "closing" the cutting glands are arranged at body height of the operator. This can occasionally lead to increased danger for the operating personnel, as has already happened, when the control mechanism fails.

As a first way to overcome this drawback, an attempt has been made to develop automatic arrangements for switching decoking tools. However, it is contrary to the fact that the relatively sensitive control mechanisms are difficult to attach to the tool that is used in a very difficult environment with heavy mechanical and thermal loads.

The inventive arranging the means for operating the built-in decoking tool for closing one or more nozzles so that the control element between the nozzles and the upper end of the tool is mounted, already ensures that accidents in a manually operated arrangement can be avoided for switching.

With the preferred arrangement, the tool when changing from the first to the second operating state or vice versa so far remain in the drum to be emptied that the cutting nozzles that emit high-pressure water jets remain covered by the drum. Even in the event that the control devices of the decoking system fails and (wrongly) signals that the tool can be changed even though it is still under high pressure, operators can approach the tool without running the risk High pressure water jets get injured.

The devices for closing one or more nozzles are designed differently. Some tools are equipped with ball valves, in other tools hollow cylinders are used, which are provided with openings for opening the nozzles. Depending on the position of the hollow cylinder, which is optionally connected to a bottom plate provided with cutouts, a high pressure water jet exits or the respective nozzle is closed by the hollow cylinder or the bottom plate. The hollow cylinder covers the cutting nozzles or releases them while the bottom plate releases or closes the drilling nozzles.

For almost any of the known devices, it is possible to provide an arrangement for moving the decoking tool, in which the operating element is mounted above the nozzles and below the upper end of the decoking tool.

It is considered to be particularly advantageous that existing and-insofar as it concerns the device for closing individual or multiple nozzles-proven technology can be equipped with the inventive arrangement.

Fig. 1

einen Längsschnitt einer Ausführungsform des erfindungsgemäßen Werkzeugs im Betriebszustand "Bohren";

Fig. 2

einen zweiten Längsschnitt einer identischen Ausführungsform des erfindungsgemäßen Werkzeugs im Betriebszustand "Bohren", der in einem Winkel zu dem Schnitt nach Fig. 1 angelegt ist;

Fig. 3

einen Längsschnitt einer Ausführungsform des erfindungsgemäßen Werkzeugs im Betriebszustand "Schneiden";

Fig. 4

einen zweiten Längsschnitt einer identischen Ausführungsform des erfindungsgemäßen Werkzeugs im Betriebszustand "Schneiden", der in einem Winkel zu dem Schnitt nach Fig. 3 angelegt ist;

Fig. 5

einen Schnitt durch ein Werkzeug einer zweiten Ausführungsform

A preferred embodiment of the invention will be explained in more detail below with reference to the FIG. Show it:

Fig. 1

a longitudinal section of an embodiment of the tool according to the invention in the operating state "drilling";

Fig. 2

a second longitudinal section of an identical embodiment of the tool according to the invention in the operating state "drilling", which at an angle to the section to Fig. 1 is created;

Fig. 3

a longitudinal section of an embodiment of the tool according to the invention in the operating state "cutting";

Fig. 4

a second longitudinal section of an identical embodiment of the tool according to the invention in the operating state "cutting", which at an angle to the section to Fig. 3 is created;

Fig. 5

a section through a tool of a second embodiment

Fig. 1 shows a tool 2 with a housing 4, two nozzles for cutting coke 6 and two other, here only hinted nozzles for drilling coke 8 and a valve 10 for opening and closing the nozzles 6, eighth

The tool 2 hangs in the operating state on a drill rod, not shown, and is introduced into a filled with coke drum. Information such as "above" or "below" refer to the in the Fig. 1 to 4 shown tool on the axis A, which is aligned with the boring bar (above) and a bore to be produced by the tool (below, not shown).

The housing 4 is formed in two parts. Arranged between the upper casing half 4a and the lower casing half 4b, which is not shown here, is the valve 10. The upper housing half 4a is attached with a flange 12 to the drill rod. It extends from there as a substantially cylindrical hollow body to the lower housing half 4b. At the end of the upper housing half 4a, which is associated with the valve 10, an annular holder 14 is formed. At this bracket 14, a valve support 16 is attached from below.

For a simpler and more precise alignment of the valve carrier 16 on the holder 14, corresponding contact surfaces 18a and 18b and 20a and 20b are provided on the holder 14 and the valve carrier 16. In the area of the contact surfaces 20a, 20b, an annular seal 22 is provided.

The valve carrier 16 is screwed to the holder 14 with screws 24, which engage in threaded holes, not shown here, in the holder 14 and the valve carrier 16.

The valve carrier 16 is a cylindrical hollow body, in which an intermediate bottom 26 is formed, which extends substantially perpendicular to the axis A. On the intermediate bottom 26 run two balls 28 of the ball valve 10. The balls 28 are positioned on the outer periphery of the intermediate bottom 26 and the valve carrier 16. In this position they are held both during the respective operating states "drilling" and "cutting" and during a change from one operating state to another by positioning aids. In the present embodiment, the positioning aid is formed as a spring 30, which is stretched between the two balls 28.

The position of the balls 28 on the intermediate bottom 26 is determined by means for guiding the balls. These means for guiding the balls 28 are formed in the present embodiment as half shells 32, which surround the upper half of the balls 28 and the spring 30-. Of the half-shells 32, a guide 34 extends upward.

The intermediate bottom 26 of the valve carrier 16 has, as in Fig. 2 shown, holes 36, whose number coincides with the number of balls 8. The valve carrier 16 has in its outer wall 38 holes 40, are used in the cutting nozzles 6.

Below the intermediate floor 26 or on its underside bearing surfaces 42a and 42b and 44a and 44b are provided. The contact surfaces 42a, b are parallel to the axis A, the contact surfaces 44a, b are perpendicular to the axis A.

The lower housing half 4b abuts against these abutment surfaces 42a, b and 44a, b and is fastened to the valve carrier by means of screws 46 which engage in threaded bores, not illustrated here, of the valve carrier 16. In the area of the bearing surfaces 44a, b, an annular seal 48 is provided.

A cavity 50 in the lower housing half 4b ensures the unimpeded flow of fluid through the bores 36 to the drilling nozzles 8, which are arranged in the lower housing half 4b. The drilling nozzles 8 are indicated here only schematically.

This in Fig. 1 and 2 shown tool 2 is in the operating state "drilling" (drilling state). In the drilling state, the balls 28 of the ball valve 10 lock the holes 40 in the outer wall 38 of the valve carrier 16. The diameter of the balls 28 is dimensioned so that the holes 40 are reliably and completely covered.

At the same time, as in Fig. 2 shown, the holes 36 in the intermediate bottom 26 of the valve carrier 16 freely. Water, which shoots into the tool 2 under high pressure from the boring bar, flows through the interior space 52 in the tool above the intermediate bottom 26, through the bores 36, then passes through the cavity 50 in the lower housing half 4b to finally pass through the nozzles 8 in FIG to leak a not shown, filled with coke drum.

In order to be able to change from the drilling state to the operating state "cutting", a device 54 for actuating the valve 10 on the tool 2 is provided. The device 54 has a cylindrical hollow body 56 which is inserted into the upper housing half 4a. The lower end of this hollow body 56 has recesses 58, which are in engagement with the guide 34 of the ball valve 10. The upper end 60 of the hollow body 56 is formed in the manner of a toothed ring. With this upper, designed in the manner of a sprocket end 60 of the hollow body 56 is a gear 62 is engaged. To the gear 62, an axis 64 is attached, which is guided through the upper housing half 4a. The axis 64 is adjusted manually with a key.

To change from the drilling state in the operating state of the "cutting" the gear 62 is actuated by turning the shaft 64. The engaging with the gear 62 hollow body 56 is rotated by the gear 62 in the upper housing half 4a. Together with the hollow body 56, the guide 34 and thus also the balls 28 of the ball valve 10 is rotated. By turning the balls 28 on the valve carrier 16, the holes 40, which had closed the nozzles 6, released (see. Fig. 3 ). The balls 28 migrate by operating the handle 64 on a circular arc until the holes 36 are completely closed (see. Fig. 4 ).

3 and 4 show a tool 2 in the operating state of the cutting. From the boring bar water flows under high pressure into the interior 2 of the upper housing half 4 and exits from the cutting nozzles 6 as the only possible outlets approximately at right angles to the axis A. The holes 36 are securely and completely closed by the overlying balls 28. The closing action of the balls 28 is thereby additionally secured in this position as well as when closing the holes 40, that the extraordinarily high water pressure, which is well above 100 bar, presses the balls to the valve carrier.

That in the Fig. 1 to 4 illustrated embodiment relates to a design of the invention, which has two nozzles 6 for cutting and two nozzles 8 for drilling. Of course, embodiments of the invention also include those embodiments which have three or more nozzles 6 or nozzles 8. Likewise, it is not necessary that the number of nozzles 6 and the nozzles 8 is the same. In particular, for embodiments of the invention having three or more nozzles requiring more than two balls 28, the positioning aid may be a separate guide for each ball. A spring 30 is then no longer required.

Such an embodiment of the multi-nozzle tool 2 shows Fig. 5 (like reference numerals are used for the same features). The tool 2 has a housing 4 and a valve 10. The valve carrier 16 is inserted into the housing. The cutting nozzles 6 are in the in Fig. 5 illustrated embodiment arranged in two layers one above the other. The nozzles 6A and 6B are diagrammatically immediate shown vertically superimposed, in fact they are arranged at an angle of about 60 ° offset from each other. This is indicated by appropriate hatching.

The balls 28, which open or close the nozzles 6 and the openings 36 which supply the drilling nozzles 8, depending on the operating state, are received in means for guiding, which fix the balls 28 in a predetermined position as a holder 33 with integrally formed guide lugs 35. The holder 33 is attached to the cylindrical hollow body 56, which belongs to the device 54 for actuating the valve 10. The guide lugs 35 cause a secure positioning of the balls 28, so that no springs are needed. The device 54 for actuating the valve otherwise corresponds to the in the Fig. 1 to 4 shown embodiments.

Between the housing 4, the valve carrier 16 and the means 33 for guiding the balls 28 are free spaces 66 which are in fluid communication with the inner space 52. The water flowing through the tool 2 in the operating state thus flows through both the interior 52 and the free spaces 66, so that any pressure difference is avoided.

Claims (13)

1. A tool (2) for disintegrating coke, having

   - a housing (4) attached to a drill stem in operation, and at which or in which

   - at least one nozzle for cutting (6) and a nozzle for drilling of coke (8) and at least one valve (10) for closing and opening the nozzles (6, 8) is arranged, wherein said tool (2) is adapted to have two different operating states and wherein said at least one valve closes off said cutting nozzles in the drilling operating state, while the drilling nozzles are closed off by said valve in the cutting operating state,

   - and wherein said housing (4), said valve (10) and said nozzles (6, 8) are adapted so that water may flow unhindered from said drill stem through said housing and said valve and through the nozzles not closed off by said valve,

   characterized in that
   the nozzles to be closed, depending on each chosen operating state, are closed off by the balls (28) of a ball valve (10).
2. The tool of claim 1, characterized in that said balls (28) are spherically formed at least in sections.
3. The tool of claim 2, characterized in that said balls (28) have at least two spherical surface sections.
4. The tool according to at least one of claims 1 to 3, characterized in that said balls (28) are symmetrical.
5. The tool of claim 1, characterized in that said balls (28) are held in position by a spring (30).
6. The tool of claim 1, characterized in that said balls (28) of said ball valve (10) engage means (32) for guiding.
7. The tool of claim 6, characterized in that said means for guiding said balls (28) of said ball valve (10) are concave shells (32) embracing said balls (28).
8. The tool of claim 1, characterized in that said valve (10) engages means (54) for operating said valve, in particular for switching over from a first operating state to a second operating state.
9. The tool of claim 8, characterized in that said means (32) for guiding said balls (28) have a guide (34) engaging means (54) for operating said valve (10).
10. The tool of claim 1, characterized in that said valve carrier (16) is arranged in said housing (4), and between said housing (4) and said valve carrier (16) there is a gap (66), wherein said gap (66) is in flow communication with said interior cavity (52) of said tool.
11. The tool of claim 1, characterized in that at least two nozzles (6) for cutting are inserted in bores (40) and at least two bores (36) are arranged in the web (26) of a valve carrier (16) of said valve (10), and in that these bores (36) are blocked by said balls (28) when said tool (2) is in said cutting operating state, and said bores (40) are blocked by said balls (28) when said tool (2) is in a drilling operating state.
12. The tool of claim 11, characterized in that said at least two nozzles (6A, 6B) are arranged one on top of the other.
13. The tool of claim 1, characterized in that said tool comprises means (54) for operating said valve (10), wherein said means (54) are arranged between said nozzles (6, 8) and the top end of said tool (2).

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