Device and method for testing decoking tools

#The invention concerns a device and a method for the testing of decoking tools.

#As is well known, decoking tools are used in refineries in context with the emptying of coke drums, in which refineries coke remains at the end of processing crude oil, the coke being collected in coke drums of e.g. 30 m of height and a diameter of 8 m. Once the coke drums are full they are emptied within the shortest possible period of time so that they will be available again as soon as possible for receiving newly accruing coke.

#For the emptying of coke drums, so called decoking tools are employed which are provided with boring nozzles and cutting nozzles. Such a tool is mounted on the lower end of a hollow drill stem which is guided on a frame above the boring drum so as to be lifted and lowered and which is supplied with pressurized water via high-performance pumps. On emptying the coke drums the decoking tool is guided through the coke drum, initially starting at the top and moving towards the bottom for boring-up a central vertical channel by means of the now rotating drill stem, wherein water jets exit from the boring nozzles arranged on the underface of the decoking tool at high-pressure, crushing the coke and pushing it away so that the required central bore can be formed in the coke drum. Having arrived at the bottom, the decoking tool is switched from boring to cutting, so that the water jets are no longer discharged from the boring nozzles but from two cutting nozzles diametrically opposing each other on the circumference of the decoking tool. The decoking tool is now lifted, again whilst rotating, by the drill stem. Herein, the water jets exiting from the cutting nozzles break the coke over the whole cross-section of the drum up to the drum wall, so that the coke may fall downwardly in the drum and may be delivered from an opening at the lower end of the drum.

#In the following, an example of embodiment will be explained in greater detail and with reference to the drawings. In the drawings, there is shown in:

#FIG. 1 is a perspective view of a testing device for decoking tools;

#FIGS. 2, 3 and 4 respectively are one side view, one top view, and one front view, each, of the testing device of FIG. 1;

#A testing device for decoking tools represented in FIGS. 1-4 has a jet housing 1, which, in its middle section, is composed of a tubular body 2 extending in a rectilinear direction and having eyes 2a as well as flanges 3, 4 at its ends. The tubular body 2 of the jet housing 1 rests on brackets 8, 9, 10, as shown in the drawing, which brackets, in the front, bear on supports 5, 6, 7, and, in the rear—when taking the drawing—, on an accessible platform 11 which can be reached via stairs 12. This structure takes into account the particular structural circumstances of this example of embodiment. At its one end, the tubular body 2 passes into an arcuate section 13, connected via flanges 3, 14, which arcuate section has a stub 47 with an opening 48 and arranged approximately within the axis of the tubular body 2, the opening 48 being closable by means of a lid 49 which can be attached detachably by means of bolts.

#Below the arcuate section 13 of the conduit the latter continues by a connecting tube 17 and. via flanges 18, 19a. by a collecting tube 19 extending approximately parallel to the tubular body 2 and below the same. In the collecting tube 19, an intermediate tubular piece 36 has been inserted by means of flange connectors 37. 38. At its end, the collecting tube 19 passes into a T-shaped tubular piece 21 and is connected to this T-shaped tubular piece 21 by flanges 20, 22.

#An arcuate tubular section 29 is connected at the other end of the tubular body 2 via flanges 4, 28, at the lower end of which tubular section 29 there is connected a flange 27 having a flange plate 26 of an intermediate tubular piece 25. The lower flange 24 of this intermediate tubular piece 25 is connected to a tubular connector piece 23 having a flange, which piece 23 passes into said T-shaped tubular piece 21 which, at its one end, is connected to a conduit 50 schematically indicated in the drawing by means of a flange 21a, whereas the other end of the T-shaped tubular piece 21 is closed and may be used for other conduit connectors. Furthermore, a water receptacle 51 connected to the conduit 50, a further conduit 52 leading to a high-pressure water pump 53, and a conduit 54 leading to a port 34, which yet has to be explained, are also indicated only schematically in the drawing.