EP3126094A1

EP3126094A1 - Water-abrasive-suspension cutting system

Info

Publication number: EP3126094A1
Application number: EP14727715.6A
Authority: EP
Inventors: Marco Linde
Original assignee: ANT Applied New Technologies AG
Current assignee: ANT Applied New Technologies AG
Priority date: 2014-04-04
Filing date: 2014-04-04
Publication date: 2017-02-08
Anticipated expiration: 2034-04-04
Also published as: KR20160141723A; CN106163742B; JP6275918B2; AU2014388985A1; CA2944227A1; CA2944227C; US20170106499A1; EP3126094B1; KR102216007B1; PL3126094T3; CN106163742A; NO3126094T3; AU2014388985B2; JP2017512668A; WO2015149867A1; US10189144B2; MX2016012954A

Abstract

The invention relates to a water-abrasive-suspension cutting system having at least one high-pressure source (2) which provides a carrier fluid under high pressure, at least one outlet nozzle (6), a high-pressure line (4) connecting the high-pressure source (2) to the outlet nozzle (6) and an abrasive-supplying sluice (16) which is connected to the high-pressure line (4) and has a shut-off element (26) at the inlet end and a shut-off element (24) at the outlet end and a sluice chamber (18) provided therebetween, a suction device (30) being provided which is connected to the sluice chamber (18) and is designed to generate negative pressure in the sluice chamber (18).

Description

Title: Water-abrasive-suspension-cutting machine

description

The invention relates to a water-abrasive suspension cutting system with the features specified in the preamble of claim 1.

WO 2013/037405 discloses a water-abrasive suspension cutting system which has a lock with a lock chamber, which makes it possible to introduce abrasive during operation in the high-pressure region of the cutting system. In such a system, there is the difficulty to fill the lock chamber sufficiently quickly with abrasive and emptied again to bring a sufficiently large Abrasismittelmenge per unit time in the high pressure area of the system can.

In view of this problem, it is an object of the invention to improve a water-abrasive suspension cutting system to the effect that during operation a larger amount of abrasive per unit time can be introduced into the high pressure area.

This object is achieved by a water-abrasive suspension cutting system with the features specified in claim 1. Preferred embodiments will become apparent from the subclaims, the following description and the accompanying figures. It should be understood that the features described below may be implemented individually or in combination with each other. The water-abrasive suspension cutting system according to the invention has, in a known manner, at least one high-pressure source which provides a carrier liquid, in particular water under high pressure. This is for example a high-pressure pump. Instead of eg water, other suitable carrier liquids can be used. Furthermore, at least one outlet nozzle is provided from which the high-pressure suspension of carrier liquid, ie preferably water, and an abrasive agent can be applied. The exit gland may be formed in a known manner for cutting or for the surface treatment of materials. The discharge nozzle is connected to the high-pressure source via a high-pressure line or a high-pressure flow path in which an abrasive is mixed under high pressure with the water provided by the high-pressure source. The high pressure source provides carrier fluid under a very high pressure, preferably a pressure of up to 2500 bar or higher. When admixing the abrasive, the high-pressure line can run at least in a partial flow through a pressure vessel in which abrasive is located, so that the abrasive from the pressure vessel is taken along by the carrier liquid and a suspension is formed.

In order to be able to introduce abrasive material from an area with ambient pressure into the high-pressure area between the high-pressure source and the outlet nozzle, ie, into the high-pressure line during operation of the cutting system, an abrasive-supply lock is provided which has an inlet-side shut-off device and an outlet-side shut-off device with one between them Lock chamber has. By opening the input-side obturator, the supply lock can be opened to the environment while at the same time the output-side obturator is closed to the high pressure area. So the lock chamber can be filled at ambient pressure. Subsequently, the input-side obturator closed and an increase in pressure in the lock chamber are made, whereupon the second obturator can be opened and the contents of the lock chamber under high pressure in the high pressure line into, for example, a pressure vessel can empty into it. Thus, by alternately opening the shut-off with appropriate pressure relief and pressurization of the lock chamber during operation Abrasivmittel be introduced from the environment in the high pressure area. The shut-off devices may be formed, for example, as ball valves.

In order to bring the abrasive as quickly as possible in the lock chamber when the input-side obturator is open, the lock chamber according to the invention is connected to a suction device which, when the first obturator is opened, can be activated to generate a vacuum in the lock chamber , By such a negative pressure generated by the suction device, the abrasive is sucked through the open inlet-side obturator in the lock chamber, d. H. an inflow of the abrasive in the lock chamber is supported by at least a negative pressure in the lock chamber. Preferably, above the lock chamber, an abrasive accumulator is arranged, from which the abrasive is moved by gravity into the lock chamber, said movement is at least supported by said negative pressure. The abrasive agent store can be used as a filling funnel, i. H. be designed as a hopper, wherein in the abrasive storage, the abrasive preferably with carrier liquid, d. H. In particular, water is kept mixed, so that the abrasive can be introduced without air inclusions from the outside into the lock chamber.

The suction device is preferably formed as a cylinder in which a piston is movable, wherein one end of the cylinder to the Lock chamber is opened towards or connected to this. When the piston is moved away from this end of the cylinder, the volume in the cylinder increases, whereby liquid is sucked from the lock chamber connected to this end of the cylinder and so in the lock chamber a negative pressure or a suction is generated, by which Input side obturator abrasive can be sucked into the lock chamber.

The piston is preferably movable via an electric, pneumatic or hydraulic drive. In this case, the drive is controlled by a control device such that, when the first obturator is opened, the piston is moved away from the first end of the cylinder, which is connected to the lock chamber, to generate a negative pressure in the lock chamber. Preferably, the piston and the cylinder are formed such that the piston in the cylinder is linearly movable. The piston is suitably sealed against the inner wall of the cylinder.

Particularly preferably, the piston is hydraulically movable, ie it has a hydraulic drive, wherein the piston is connected to a drive piston in a drive cylinder and the drive piston in the interior of the drive cylinder for movement of the piston with carrier liquid from the high-pressure line can be acted upon. So can be dispensed with a separate hydraulic to drive the piston. Instead, the pressure of the carrier liquid in the high-pressure region or in the high-pressure line can be used to move the piston in the suction device. The drive piston may be arranged with the piston of the suction device in a common cylinder. However, it can also be provided separate cylinder. The drive piston and the piston of the suction device preferably move along the same axis and are connected to one another for the transmission of force and movement in a suitable manner, preferably firmly. It However, it is also possible to arrange the piston of the suction device and the drive piston in a different manner relative to each other, for example, side by side, and to couple together for common movement in a suitable manner.

The application of carrier fluid from the high-pressure line to the drive cylinder is preferably effected by valves actuated by a control device, i. H. in particular causes electrically or pneumatically actuated valves.

For this purpose, the drive cylinder is further preferably connected to the high-pressure line via at least one valve on at least one side of the drive piston. When the valve is opened, so the cylinder is filled with carrier liquid from the high-pressure line and the drive piston is pressurized on one side, so that the drive piston can be moved in a side facing away from this side in the drive cylinder. As a result of the movement coupling described, the piston of the suction device is correspondingly moved in order to generate the negative pressure in the lock chamber.

Particularly preferably, the lock chamber opens via its output-side obturator in a pressure vessel, which is located in the high pressure line or a branch of the high pressure line. Preferably, the lock chamber is arranged vertically above the pressure vessel, so that the contents of the lock chamber can be emptied by gravity in the pressure vessel with open outlet-side obturator. The pressure vessel may be the area in which, as described above, the high-pressure carrier liquid mixed with the abrasive to form a suspension. Ie. by the flow of the carrier liquid, the abrasive is rinsed out of the pressure vessel. The slurry flow downstream of the pressure vessel then enters the exit nozzle and is discharged through this. In this case, only a partial flow or one of a plurality of parallel flow paths of the high-pressure line is preferably guided through such a pressure vessel. However, according to a particular embodiment of the invention, a main branch of the high-pressure line extends from the high-pressure source to the pressure vessel and the pressure vessel is located in a side branch parallel to the main branch, with the main branch and the secondary branch merging upstream of the outlet nozzle. Thus, the main branch forms a bypass, which is not guided by the pressure vessel. Only the flow in the secondary branch is used in this embodiment to promote the abrasive from the pressure vessel. Ie. In the pressure vessel, the flow from the side branch first mixes with the abrasive and conveys the abrasive to a mixing point, at which the side branch and the main branch unite. There, the suspension from the side branch is then further diluted by the flow in the main branch and it forms the suspension, which then further downstream of the outlet nozzle exits.

According to a further preferred embodiment, the lock chamber is connected via a pressure line to the high pressure line, wherein in the pressure line, a first pressure compensation valve is arranged in the form of a shut-off valve and wherein by opening this first pressure compensation valve, the lock chamber is pressurized. The shut-off valve may be formed in any suitable manner for switching a high pressure, as mentioned above. Preferably, the shut-off valve is designed as a needle valve. The shut-off valve can be actuated electrically, pneumatically, hydraulically or in another suitable manner and is preferably controlled by a control device of the overall system. By opening the shut-off valve is a connection between the high pressure area, ie between the high pressure line and the lock chamber made so that carrier liquid can flow under high pressure into the lock chamber and so can increase the pressure in the lock chamber to the substantially same level as in the high pressure line. Thus, after the closing of the inlet-side shut-off device of the lock chamber, the pressure in the lock chamber can be increased before the outlet-side shut-off element is opened. In the lock chamber thus a pressure equalization with the high-pressure line is made before opening the outlet-closing obturator.

More preferably, the lock chamber is connected to a drain line, which is connected via a second pressure compensating valve in the form of a shut-off valve with a non-pressurized drain, wherein the Ablassleifung can be opened to the non-pressurized flow by opening the second Druckausgleichsvenfils. The second pressure compensating venfil can be configured in a corresponding manner to the above-mentioned pressure compensation valve. The second pressure compensation valve is used to reduce the pressure in the interior of the lock chamber after closing the outlet-side obturator and before opening the inlet-side obturator, in particular substantially to reduce the ambient pressure. Only when the pressure in the lock chamber has been reduced accordingly, then the inlet-obturator is opened to refill the lock chamber again with Abrasivmiftel.

According to a further preferred embodiment, the lock chamber can be connected to a drain line which ends in a pressure chamber of a rechargeable battery. This may be a separate Ablassleifung or be the Ablassleifung, which also opens via a shut-off valve in a non-pressurized drain. Via the discharge line, which is connected to the pressure chamber of an accumulator, it is possible, the pressure in the lock chamber in the accumulator reduce, so that no or less liquid from the lock chamber must be discharged to the outside. It can thus be a pressure equalization or a pressure reduction in a closed system. In this case, it is also possible to combine the use of an accumulator with a non-pressurized discharge, in such a way that first the pressure is reduced by a certain amount by transferring liquid into the accumulator and then the residual pressure by opening the shut-off valve to the non-pressurized discharge is reduced down.

The accumulator is more preferably a cylinder accumulator and the discharge line is connected to a first pressure chamber of the cylinder accumulator, in which a piston, which separates the first pressure chamber from a second pressure chamber, is arranged to be movable. The second pressure chamber is preferably via at least one valve pressure and pressure relieved. When the piston is in a first position, in which it minimizes the first pressure chamber, the second pressure chamber can be relieved of pressure via a valve, so that liquid or water can flow out of the lock chamber into the first pressure chamber via the outlet conduit, wherein the piston moves into the second pressure chamber and reduces it as the first pressure chamber increases. By pressurizing the second pressure chamber, the piston can be moved back to its original position. In addition, a back pressure can be built up via the second pressure chamber, so that the movement speed of the piston can be controlled or reduced, so that a slow pressure reduction in the lock chamber is possible. The second pressure chamber of the cylinder accumulator is further preferably connected via at least one valve switchable to the high pressure line or a non-pressurized outlet. The valve can be installed in any suitable manner, for example, be designed as a needle valve. The valve may have, for example, an electric, pneumatic or hydraulic drive and is preferably controlled by a central control device which controls the filling process. When the valve communicates the second pressure chamber of the cylinder accumulator with the high-pressure line, the second pressure chamber is supplied with liquid from the high-pressure line, so that the piston in the cylinder accumulator in the first pressure chamber or in the direction of the first pressure chamber are moved can, so that it is reduced. When the valve is switched to communicate the second pressure space with a non-pressurized outlet, simultaneously closing the connection to the high-pressure line, the piston may move toward the second pressure space so that the first pressure space increases to expel liquid to absorb the lock chamber. These Schalfvorgänge can be realized by a suitable Ventilschalfung of one or more valves. For example, two separate valves may be provided, with one valve opening or closing the connection to the high pressure line and a second valve opening or closing a connection to the non-pressurized outlet.

More preferably, in the drain line upstream of the accumulator, i. H. in particular of the cylinder accumulator be arranged a throttle. This provides for a slower pressure reduction of the pressure in the lock chamber by throttling the liquid flow from the lock chamber to the accumulator.

According to a further preferred embodiment of the invention, at least one pressure accumulator is arranged in the high-pressure line or connected to the high-pressure line. This pressure accumulator can be designed, for example, as an additional volume filled with high-pressure carrier liquid or, for example, as a bladder accumulator be. The pressure accumulator serves to reduce a pressure drop in the high-pressure region, ie in the high-pressure line, when a pressure equalization takes place in the lock chamber from the high-pressure region or the high-pressure line. If, for example, a first pressure equalizing valve, as described above, is opened, a connection is established between the lock chamber, in which initially atmospheric pressure prevails, and the high-pressure line. As a result, there is an increase in the pressure in the lock chamber, ie a pressure equalization, but which can lead to a pressure drop in the high pressure line on the other side. By a corresponding pressure accumulator this pressure drop can be minimized or prevented.

According to a further preferred embodiment of the invention, the lock chamber is connected via the inlet-side obturator with an outlet of Abrasivmittelspeichers, wherein in the output of a movable closure member is arranged, which is hollow and open to an upper and a lower end, wherein the closure element with its lower end closes the outlet and extends with its upper end over a maximum level for the abrasive out addition. The Abrasivmit- telspeicher may for example be designed as a hopper, wherein the output of the hopper is located at its lower tapered end. This outlet opens into the inlet-side obturator of the lock chamber. In addition to this input-side obturator, the closure element is provided, which closes the output, for example in the form of a plug. By vertical movement of the closure element, the output can be opened and closed. At the same time, however, the shutter member is preferably formed to have a lower opening which is opened into the exit and hollow in its interior. The cavity in the interior of the closure element provides a Connection to a second opening at the upper end of the closure element ago. In this case, the closure element is formed so long or has an upwardly extending axial extension, that the opening is located at the upper end above the maximum Füll- state for the abrasive in the Abrasivmittelspeicher. This causes, when the closure element closes the outlet, a connection remains through the cavity in the interior between the outlet and the upper end or the opening at the upper end. Through this opening, however, no Abrasivmiffel can flow into the outlet, since the opening is located at the upper end above the maximum level for the abrasive. However, when the outlet is closed by the closure element, this connection ensures that liquid or water can flow out of the lock chamber through the closure element when the obturator is open, and then exits through the opening at the upper end of the closure element. This is expedient because liquid is pushed back into the lock chamber when moving back a piston of the suction device or optionally a piston of an accumulator. If this happens when the inlet-side shut-off device is open, the liquid can then be forced into the abrasive reservoir through the closure element. The abrasive storage is preferably equipped with a level monitoring for both the abrasive and for liquid, so that it is always ensured that a liquid-abrasive mixture is present in the abrasive storage. The described closure element preferably has a closure plug at its lower end, through which extends at the upper end a tubular extension which establishes the connection between the two open ends.

The closure element with the passage in its interior has the further advantage that it is possible to supply the abrasive by means of the Locking element to prevent, even if the input-side obturator is still open. In this state, it is then possible in particular for water or carrier liquid to be able to flow further through the opening in the interior of the closure element through the closure element and the inlet-obturator, while the supply of abrasive is prevented, for example, by the closure stopper at the lower end of the closure element , This makes it possible for the inlet-side obturator to be flushed with carrier liquid or water in order to make it substantially free of abrasive medium before the closing of the inlet-side shut-off element.

The invention will now be described by way of example with reference to the accompanying drawings. 1 schematically shows a water-abrasive suspension

Cutting system according to a first embodiment of the invention,

2 shows a water abrasive suspension cutting system according to a second embodiment of the invention,

3 shows a water-abrasive-suspension cutting system according to a drift embodiment of the invention; FIG. 4 shows a schematic view of the filling funnel in FIGS. 1 to 3 in the closed state;

Fig. 5 is a view of the hopper of FIG. 4 in the open state.

The water-abrasive suspension cutting system shown in Figure 1 has a high pressure source in the form of a high-pressure pump 2, which is connected via a high pressure area or a high pressure line 4 with an outlet nozzle 6. The high-pressure pump 2 provides water as a carrier fluid under high pressure, wherein the pressure can be up to 2500 bar or more. The main line 8 runs directly from the high-pressure pump 2 to the outlet nozzle 6, while the secondary branch 10 branches off from this main branch 8 and forms a bypass, which passes through a pressure vessel 12 runs. In the pressure vessel 12 is an abrasive, such as a mineral abrasive such as garnet sand, corundum, olivine or river sand. When flowing through the pressure vessel 12, a mixing between the abrasive and the water occurs, so that the water entrains the abrasive, or rinses out of the pressure vessel 12. In a mixing point 14, which is located upstream of the outlet nozzle 6, the secondary flow 8 ends on the output side of the pressure vessel 12 back into the main stream 8 and thus mixes this entrained from the pressure vessel 12 abrasive, so formed in the mixing point 14, the final suspension is, which then emerges from the outlet nozzle 6 to the outside. In the branch 10, a valve (not shown here) can be provided to switch off the secondary branch 10, with which the supply of abrasive to the water flow can then be switched off.

Since the pressure vessel 12 can accommodate only a certain amount of abrasive, it is necessary for continuous operation of the system to replenish the pressure vessel 12 during operation. For this purpose, an abrasive agent supply lock 16 is provided according to the invention. This has a lock chamber 18, which consists of an inlet region 20 and an intermediate container 22. The lock chamber 18 is arranged vertically above the pressure vessel 12 and separated therefrom by an outlet-side obturator in the form of an outlet-side ball valve 24. At the upper end de, the lock chamber 18 on an input-side ball valve 26, which forms an input-side obturator. Vertically above the input-side ball valve 26, a hopper 28 is arranged, which will be described with reference to Figures 4 and 5 in more detail. At the inlet region 20 of the lock chamber 18 further includes a suction device 30, which here has a cylinder 32 with a linearly movable piston 34 in this. The piston 34 is fixedly connected to a drive piston 36 which is linearly movable in an axially adjoining the cylinder 32 drive cylinder 38.

In addition, a pressure line 40, which branches off from the high-pressure line 4, in this case the secondary branch 10, opens into the lock chamber 18. In the pressure line 40, a first pressure compensation valve 42 is arranged. Furthermore, the lock chamber 18 is connected to an outlet line 44, in which a second pressure compensating valve 46 is arranged and which opens downstream of the second pressure compensating valve 46 into a pressure-free outlet 48.

At the auxiliary branch 10, a first pressure transducer 50 and at the lock chamber 18, a second pressure transducer 52 is arranged. Furthermore, the pressure line 4 still has an accumulator in the form of a pressure accumulator 54.

In the example shown in FIG. 1, a hydraulic drive is provided for the piston 34 of the suction device 30, which is formed by the drive cylinder and the drive piston 36. For this purpose, the drive cylinder 38 is connected at a first, the piston 34 facing side of the drive piston 36 via a valve 56 to the high pressure line 4. Accordingly, the drive cylinder 38 is connected to a second side of the drive piston 36, which faces away from the piston 34, via a further valve 58 also connected to the high-pressure line 4. At the connection of the valve 56 with the drive cylinder 38th In addition, a drain valve 60 is arranged. Accordingly, a drain valve 62 is arranged at the connection of the valve 58 to the drive cylinder 38. On the output side of the valves 56, 58, a check valve 64, 66 is also arranged in each case.

When the piston 34 in the cylinder 32 moves away from the lock chamber 18, d. H. is moved to the drive cylinder 38, a negative pressure can be generated in the lock chamber 18. This negative pressure causes, when the ball valve 26 is open on the inlet side, abrasive particles from the filling funnel 28 to be sucked into the inlet region 20 in the lock chamber 18 in addition to the force of gravity acting through a negative pressure. To be able to move the piston 34 accordingly, the drain valve 62 is opened and at the same time the valve 56 is opened so that the drive piston 36 is pressurized on its side facing the piston 34 and thus moved in a direction in which it moves together with the piston 34 away from the lock chamber 18. Due to the fact that the lock chamber 18, d. H. whose inlet region 20, facing region of the cylinder 32 is connected to this inlet region 20, water is sucked out of the lock chamber 18 in this way and there is a negative pressure in the lock chamber 18.

In order to move the piston 34 back in the direction of the lock chamber 18, the valve 56 is closed. Also, the drain valve 62 is closed. Conversely, then the drain valve 60 and the valve 58 are opened, so that the piston 34 remote from the side of the drive piston 36 is pressurized and so the drive piston 36 and the piston 34 are moved back in the opposite direction.

Overall, the filling process of the pressure vessel 12 with abrasive agent according to the invention now takes place as follows. First, by short-term Opening the second pressure compensation valve 46, the interior of the lock chamber 18 relieved of existing residual pressure, wherein liquid flows from the inlet region 20 via the drain line 44 into the drain 48. Thereafter, the pressure compensation valve 46 is closed again. Further, the piston 34 is moved by the drive described above in a first end position in which it is located at the end facing the lock chamber 18 end, ie the drive cylinder 38 facing away from the end of the cylinder 32. Ie. In this state, the volume of the cylinder 32 facing the lock chamber 18 and connected to it is minimal. During this movement of the piston 34, the inlet-side ball valve 26 is opened when the pressure compensation valve 46 is closed. Excess water from the lock chamber 18 through the input-side ball valve 26, as described below with reference to Figures 4 and 5, pressed into the hopper. Subsequently, as will be explained with reference to FIGS. 4 and 5, the outlet of the filling funnel 28 is opened, so that abrasive means from the filling funnel 28 can enter the inlet region 20 of the lock chamber 18 due to gravity. To assist or accelerate this ingress of abrasive, the drive piston 36 is moved to the end of the drive cylinder 38 facing away from the cylinder 32 by opening the drain valve 62 and the valve 56. In this case, the piston 34 moves with it, so that the volume of the cylinder 32, which faces the inlet region 20 of the lock chamber 18 and connected thereto, increases. As a result, a negative pressure is generated in the lock chamber 18, through which the abrasive from the hopper 28 is additionally sucked. When the lock chamber 18 is sufficiently filled with abrasive, the movement of the drive piston 36 and the piston 34 is stopped by closing the valve 56 and the drain valve 62 and the input-side ball valve 26 of the lock chamber 18 is closed. Then, by opening the valve 58, the driving cylinder is pressurized so that the driving piston 36 is moved forward together with the piston 34, that is, moved toward the lock chamber 18, so that the volume facing the lock chamber 18 in the cylinder 32 decreases. Thus, the piston 34 contributes to the pressure build-up in the interior of the lock chamber 18. Furthermore, the first pressure compensation valve 42 is opened, whereby the lock chamber 18 is acted upon by the pressure in the high-pressure line 4 or in the high-pressure region. Ie. There is a substantially complete pressure equalization between the high pressure line 4 and the lock chamber 18 instead. This is monitored by the pressure transducer 50 and 52. In order to minimize the pressure drop in the high pressure line 4 at this pressure equalization, a pressure accumulator 54 is present at this. When a pressure equalization, ie the same pressure in the auxiliary branch 10 and in the lock chamber 18 is detected via the pressure sensors, ie after the pressure equalization has been completed, the outlet-side ball valve 24 of the lock chamber 18 is opened, whereby the abrasive agent from the lock chamber 18, ie the intermediate container the lock chamber 18 due to gravity in the pressure vessel 12 passes. In this transition, the pressure compensation valve 42 preferably remains open to allow drainage of the intermediate memory 22 when it is emptied. That is, via the pressure compensation valve 42 and the pressure line 40 can flow carrier liquid or water into the lock chamber 18, while the abrasive from the buffer 22 passes through the open ball valve 24 into the pressure vessel 12. After complete emptying of the abrasive from the lock chamber 18, which can be detected by other sensors, not shown here, such as photoelectric sensors, the output-side ball valve 24 is closed again. In this case, the pressure compensation valve 42 is closed. In the next step, a pressure equalization between the lock chamber 18 and the atmosphere by the valve 56 is opened when the valve is closed, whereby the drive piston 36 together with the piston 34 backwards, that is moved away from the lock chamber 18. Thus, the lock chamber 18 facing volume of the cylinder 32 is increased and the pressure in the lock chamber 18 is reduced. Subsequently, the second pressure compensating valve 46 is opened to the outlet 48 for complete pressure equalization. When this pressure equalization has taken place, the second pressure compensating valve 46 is closed and the inlet-end ball valve 26 is opened again. Subsequently, by opening the valve 58 and opening the drain valve 60, the drive piston 36 is pressurized in such a way that the piston 34 in the cylinder 32 is moved back into its end position facing the lock chamber 18, with the liquid returning from the cylinder 32 pressed into the lock chamber 18 and from this through the open soapy inlet ball valve 26 into the hopper 28, as will be explained with reference to Figures 4 and 5. In the next step, the outlet of the filling funnel 28 is opened again and the filling of the lock chamber 18 begins again. Thus, in continuous operation of the cutting system, the pressure vessel 12 can always be filled via the lock chamber 18 with Abrasivmitfel.

FIG. 2 shows a second variant of a water-abrasive suspension cutting system according to the invention, which is constructed essentially identically to the system according to FIG. In the following, only the differences will be described. In Figure 2, only the Venfile 56 and 58 are shown as a drive for the Anreibiebskolben 36. However, it is to be understood that, according to the fold-out according to FIG. 1, expediently also the drainage valves 60 and 62 as well as the check valves 64 and 66 can be arranged. In the example shown in FIG. 2, there is a throttle 68 on the drain line 44 additionally an accumulator in the form of a cylinder accumulator 70 is connected. In this case, the discharge line 44 is connected via the throttle 68 with a first pressure chamber 72 of the cylinder accumulator 70. The first pressure chamber 72 is separated by a longitudinally displaceable piston 74 from a second pressure chamber 76 in the interior of the cylinder accumulator 70. The second pressure chamber 76 is connected via a first valve 78 to the pressure line 4 and via a second valve 80 to a drain 82 which has ambient pressure or atmospheric pressure. In the example shown in Figure 2, the pressure relief, ie the pressure equalization of the lock chamber 18 to the ambient pressure can be done in two steps. In the first step, the pressure equalization takes place via the cylinder accumulator 70 in that the second valve 80, which forms a drain valve, is opened to the outlet 82. This makes it possible for fluid to flow through the throttle 68 into the first pressure chamber 72 and to move the piston 74 in the direction of the second pressure chamber 76, so that the second pressure chamber 76 is reduced in size. A remaining residual pressure in the interior of the lock chamber 18 can then be reduced in the manner described with reference to FIG. 1 via the second pressure compensating valve 76. In order to move the piston 74 back in the cylinder accumulator 70, the first valve 78 is opened in the closed state of the second valve 80, so that the second pressure chamber 76 is acted upon by high pressure fluid from the high pressure line 4 and so the piston 74 back to the first pressure space 72 is moved, whereby the second pressure chamber 72 is reduced. When closed ball valve 26 so an increase in pressure in the lock chamber 18 is achieved. This pressure increase takes place after filling the lock chamber 18 and closing the ball valve 26 before further complete pressure equalization by opening the pressure compensation valve 42, as described above.

A third embodiment of the invention is shown in FIG. This embodiment substantially corresponds to that shown in FIG Embodiment with the only difference that for the drive of the piston 34 of the suction device 30, a separate pneumatic drive via the pneumatic ports 84 and 86 is provided on the drive cylinder 38. The pneumatic connections 84 and 86 are subjected to pressure in accordance with the above description of the hydraulic variant in order to move the drive piston 36 together with the piston 34. To the pneumatic ports 84 and 86, a separate pneumatic control system is connected accordingly, which may preferably be used when other elements of the system, in particular valves, such as the pressure compensation valves 42 and 46 are pneumatically operated.

The function of the hopper 28 will be described with reference to Figures 4 and 5 in more detail. The hopper 28 has at its lower end to an outlet 88, which as described above above the input-side ball valve 26 of the lock chamber 18 is arranged. The hopper 18 is filled in operation with water 90 and abrasive 92 so that the abrasive 92 enters the lock chamber 18 in the wet state, so that the passage of air into the lock chamber 18 is prevented.

The inlet of the abrasive into the lock chamber 18 is not controlled solely by the inlet-side ball valve 26, but additionally via a closure element 94 in the hopper 28. The closure element 94 has at its lower end a closure stopper 96 which is formed so that it can sealingly engage the inside of the inlet funnel 28 surrounding the outlet 88, as shown in FIG. In this state, no abrasive agent 92 can enter the outlet 88. In addition, however, the closure element 94 has a tube 98 which extends through the stopper 96 to the outlet 88 and at its lower ren end has a lower opening 100. In the opposite direction, the tube 98 extends from the stopper 96 up over the water level 102 to a arranged at the top of the hopper 28 pneumatic cylinder 104. Via the pneumatic cylinder 104, the tube 58 is vertically movable, so that it, as shown in FIG 5, together with the closure plug 96 can be moved to a vertically upper position in which the closure plug 96 is removed from the inner wall of the hopper 28, thus releasing an annular gap 106 through which the abrasive agent 92 can flow into the outlet 88 , It is to be understood that instead of a pneumatic drive via the pneumatic cylinder 104, any other suitable linear drive could be used to move the tube 98 with the stopper 96, ie, to move the stopper 94 in the vertical direction.

In addition to the lower opening 100, the tube 98 has an upper opening 108, which opens at the outer periphery of the tube 98. The upper opening 108 is located above the level, ie the maximum level 1 10 for the abrasive 92. This prevents that in the closed state of the filling funnel 28 shown in FIG. 4, abrasive agent 92 can pass through the upper opening 108 into the outlet 88. For the abrasive 92, the exit 88 is closed in the state and can only be opened by lifting the closure element 94 vertically. At the same time, however, it is open for water, which flows from below from the lock chamber 18 when the piston 34 moves back through the inlet-side ball valve 26. Ie. This water, which is displaced from the lock chamber 18 when the piston 34 and optionally the piston 74 are moved back, can enter the lower opening 100 of the tube 98 and exit through the upper opening 108 above the abrasive 92 into the filling funnel 28. In addition, the tube 98 has a further function, namely, that before the closing of the input-side ball valve 26, this can be rinsed to remove abrasive from the ball valve 26. For this purpose, before the end of the suction movement of the piston 34, the abrasive supply is interrupted by lowering the closure element 94. Due to the further suction movement of the piston 34 but then in the lock chamber 18 is still a suppression, so that water from the hopper via the upper opening 108, is sucked through the tube 98 from the lower opening 100 and flows through the still open ball valve 26 , Only after this flushing the ball valve 26 is then closed, as described with reference to Figures 1 - 3 for the filling.

At the hopper 28 may additionally sensors not shown here for monitoring the water level 102 and the filling level 1 10 of the abrasive 92 may be arranged to automatically refill water and abrasive can. These can be eg photoelectric barriers. Further level sensors, for example in the form of light barriers, can be arranged on the intermediate container 22 and the pressure container 12. About level sensors on the pressure vessel 12 can be detected when it must be filled. About level sensors on the intermediate container 22 can be detected when it is completely emptied, so that the lower ball valve 24 can be closed again. It can also be detected when the intermediate container 22 is sufficiently filled with abrasive agent before the abrasive agent feed from the filling funnel 28 is interrupted. Thus, the entire filling process can be automated via a control device. LIST OF REFERENCE NUMBERS

2 high pressure pump

4 high pressure line

6 outlet nozzle

8 main branch

10 secondary branch

12 pressure vessels

14 mixing point

1 6 abrasive supply sluice

18 lock chamber

20 inlet area

22 intermediate container

24 output-side ball valve

26 input-side ball valve

28 filling funnel

30 suction device

32 cylinders

34 pistons

36 drive piston

38 drive cylinder

40 pressure line

42 first pressure compensation valve

44 drain line

46 second pressure compensating valve

48 expiry

50 first pressure transducer

52 second pressure transducer

54 pressure accumulator

56, 58 valve

60, 62 drain valves

64, 66 check valves

68 throttle Cylinder accumulator first pressure chamber piston

second pressure chamber first valve second valve drain

Pneumatic connections output

water

Abrasive agent Closing element Closing stopper Tube

lower opening water level pneumatic cylinder gap

upper opening level

Claims

Expectations

Water-abrasive suspension cutting system with at least one high-pressure source (2), which provides a carrier liquid under high pressure, at least one outlet nozzle (6), a high-pressure line (4) connecting the high-pressure source (2) to the outlet nozzle (6), and a high-pressure line (4). the abrasive agent supply lock (16) connected to the high-pressure line (4), which has an input-side shut-off element (26) and an output-side shut-off element (24) with a lock chamber (18) arranged between them

marked by

a suction device (30) connected to the lock chamber (18), which is designed to generate a negative pressure in the lock chamber (18).

Water-abrasive suspension cutting system according to claim 1, characterized in that the suction device (30) is designed as a cylinder (32) with a piston (34) movable therein, one end of the cylinder (32) facing the lock chamber (18 ) is open.

Water-abrasive suspension cutting system according to claim 2, characterized in that the piston (34) can be moved via an electric, pneumatic or hydraulic drive.

Water-abrasive suspension cutting system according to claim 2 or 3, characterized in that the piston (34) is hydraulically movable, the piston (34) being connected to a drive piston (36) in a drive cylinder (38) and the drive piston ( 36) inside the drive cylinder (38) to move the piston Bens (34) can be acted upon with carrier liquid from the high-pressure line.

Water-abrasive suspension cutting system according to claim 4, characterized in that the drive cylinder (38) is connected to the high-pressure line (4) on at least one side of the drive piston (36) via at least one valve (56, 58).

Water-abrasive suspension cutting system according to one of claims 1 to 5, characterized in that the lock chamber (18) opens via its outlet-side shut-off element (24) into a pressure container (12) which is in the high-pressure line (4) or a branch ( 10) is located in the high pressure line (4).

Water-abrasive suspension cutting system according to claim 6, characterized in that, starting from the high-pressure source (2), a main branch (8) of the high-pressure line (4) is led past the pressure vessel (12) and the pressure vessel

(12) is located in a secondary branch (10) parallel to the main branch (8), the main branch (8) and the secondary branch (10) joining upstream of the outlet nozzle (6).

Water-abrasive suspension cutting system according to one of the preceding claims, characterized in that the lock chamber (18) is connected to the high-pressure line (4) via a pressure line (40), with a first pressure compensation valve (42) in the pressure line (40). is arranged in the form of a shut-off valve and by opening this first pressure compensation valve (42), the lock chamber (18) can be pressurized. Water-abrasive suspension cutting system according to one of the preceding claims, characterized in that the lock chamber (18) is connected to a drain line (44) which has a pressure-free drain (48) via a second pressure compensation valve (46) in the form of a shut-off valve. is connected, wherein by opening the second pressure compensation valve (46), the drain line (44) can be opened to the unpressurized drain (48).

Water-abrasive suspension cutting system according to one of the preceding claims, characterized in that the lock chamber (18) is connected to a drain line (44) which ends in a pressure chamber (72) of an accumulator (70).

1 1 . Water-abrasive suspension cutting system according to claim 10, characterized in that the accumulator is designed as a cylinder accumulator (70) and the drain line (44) ends in a first pressure chamber (72) of the cylinder accumulator (70). in which a piston (74), which separates the first pressure chamber (72) from a second pressure chamber (76), is movably arranged, wherein the second pressure chamber (76) can be pressurized and relieved of pressure via at least one valve (78, 80).

Water-abrasive suspension cutting system according to claim 1 1, characterized in that the second pressure chamber (76) of the cylinder accumulator (70) can be switched via at least one valve (78, 80) to the high-pressure line (4) or an unpressurized outlet ( 82) can be connected.

13. Water-abrasive suspension cutting system according to one of claims 10 to 12, characterized in that in the drain line A throttle (68) is arranged in the position (44) upstream of the accumulator.

Water-abrasive suspension cutting system according to one of the preceding claims, characterized in that the high-pressure line (4) is connected to at least one pressure accumulator (54).

Water-abrasive suspension cutting system according to one of the preceding claims, characterized in that the lock chamber (18) is connected to an output (88) of an abrasive medium storage (28) via the inlet-side shut-off element (26), wherein in the output (88) a movable closure element (94) is arranged, which is hollow and is open to an upper and a lower end, the closure element (94) closing the outlet (88) with its lower end and with its upper end over a maximum fill level (1 10) for the abrasive (92) extends.