EP2356339A1 - Clamping mechanism for cylinder liners, use thereof, and mud pump comprising a clamping mechanism - Google Patents

Abstract

The invention relates to a clamping mechanism for cylinder liners of a pump system and a piston or plunger pump for conducting drilling fluid when sinking boreholes especially in the field of oil and natural gas extraction. Said pump system comprises a pump unit and a driving rotary drive unit. The invention further relates to the use of a clamping mechanism in a piston or plunger pump. The clamping mechanism according to the invention for a cylinder liner of a piston or plunger pump is characterized in that a cylinder liner holder (2) and a bracing element (4) are provided on the piston or plunger pump, the cylinder liner (5) or part of the cylinder liner (5) is arranged between the bracing element (4) and the cylinder liner holder (2), and the bracing element (4) and the cylinder liner holder (2) are interconnected using connecting means (3), wherein the connecting means (3) or the bracing element (4) have/has devices (9) for measuring or monitoring at least one tensile stress.

Description

 Clamping device for

Cylinder liners and their use and rinsing pump with

clamping device

description

The invention relates to a clamping device for cylinder liners of a pump system and a piston or plunger pump for pumping flushing fluid when drilling holes in particular in the field of oil and gas extraction. This pump system consists of a pump unit and a driving rotary drive device. Furthermore, the invention relates to the use of a clamping device in a piston or plunger pump.

The pressing of the flush or drilling fluid through the pump system when drilling holes in the drill string or the hole pursues several goals. The drilling fluid is used for discharging the excavated cuttings or debris, the cooling and lubricating of the drilling tool located at the bottom of the hole or its drive. The pressure generated in the borehole must balance with the gases and liquids in the surrounding rock.

To generate the necessary volume flow, which is in the range of 3000 l / min and to generate the required pressure, which can be up to 500 bar, extremely powerful pump systems are required.

By default, pressure and flow are generated by the movement of one or more displacers (pistons) which create a periodically changing, outwardly sealed working space. These reciprocating engines are characterized by the fact that they the rotational movement of the rotary drive device via a crank mechanism in an axial movement that moves the piston, implemented. A variation is the execution of the piston as a plunger there.

The working space is formed by the cylinder liner and the piston moving in it.

The cylinder liner in its particular application in rinsing pumps has features compared to e.g. to internal combustion engines or other piston pumps.

On the one hand, these cylinder liners are subject to increased wear due to the extremely aggressive and, in particular, solids, abrasive conveying medium, the drilling fluid.

On the other hand, the pressure and flow rate of a rinsing pump can not be adjusted exclusively by the variation of the speed, but also by the variation of the piston used. This is done by inserting different pistons with matching cylinder liners into the pumps.

Thus, the following requirements are imposed on the cylinder liner and in particular on their attachment:

Due to wear and insertion or conversion of the system to other pressures or volumes, the attachment must allow short makeready times and low workload.

The cylinder liner must be pressed with a defined contact force against the recording to ensure the function of the local seal. Both components form the high pressure section of the System. Leaks in this area are both dangerous and costly.

Both the working environment and the existing tool must be referred to in the drilling industry as extremely rough or coarse. In addition, the existing drilling fluid is usually aggressive. Thus, another requirement is a fastener that is robust and corrosion resistant.

According to the known prior art cylinder liners are connected via three different systems with the pressure-carrying part of the flushing pump, called water part.

The first system has a wing clamp with a conical flank, wherein the contact pressure is provided by a cone. The contact pressure is generated by screws that pull the clamp around the cylinder liner and the receptacle. The clamp lies with its straight edge on the cylinder liner and with the conical part on the corresponding counterpart on the receptacle.

The wing clamps have the great disadvantage that they are very cumbersome and the torque can be applied only very inaccurate about a torque wrench on the cylinder liner. In addition, this factor scatters strongly through the conical surface, which can be worn and / or polluted (oily), which has a direct influence on the transmitting

Contact force has. The assembly of the clamp is extremely power consuming and carries a certain risk of injury. A check of the contact pressure is not possible without renewed tightening.

The second system has a hydraulically biased pin with spring clamp. In this system, the bearing bolts are elongated with a hydraulic pump or the hydraulic force acts against separate spring package and thus generates a deflection. The system is bolted torque-free. After releasing the pressure, the required contact pressure is purely mechanical in the system.

The hydraulic system offers the great advantage of a precise

Contact pressure of the cylinder liner, which is also referred to as a liner. The disadvantage, however, that cylinder liner and clamping element in two crane strokes and thus must be lifted separately into it. In addition, a hydraulic pump and hydraulic oil must be available. The hydraulic components and in particular the filler neck tend to be damaged or susceptible to interference and repair. Due to the more complex structure, the system is about twice as expensive as the wing clamp with liner holder. A subsequent control of the contact force is also not possible here, although there is the risk of loosening or loosening of the cylinder liner or the liner due to vibration through the drilling process or the flushing process.

The third system clamps the cylinder liner by an external thread. The clamp has an externally threaded member which is slipped over the cylinder liner and supported against it. Together, these elements are screwed into an inner thread attached to the water part, wherein the required contact force is applied by the pitch of the thread.

This system is both mechanically very simple and easy to use. Through the thread a very uniform contact force is applied to the seal. However, the only but very imprecise way of applying torque is to continue hammering the nut with a hammer for as long as the mechanic's power allows. The only control is the leak control during operation. The

Thread is also prone to corrosion and damage, which, with the concomitant wear to an even greater dispersion of Contact force leads. In addition, the force of the mechanic provides a barely calculable factor.

The object of the invention is therefore to provide a fastening device which avoids the disadvantages of the prior art and at the same time is inexpensive and easy to use and a uniform and defined contact pressure of the sealing surface of the cylinder liner, and thus their function guaranteed. Furthermore, it is an object of the invention to provide a suitable piston or plunger pump and a method for mounting.

The object is solved by the features of claims 1 and 13 and 14. The subclaims specify further advantageous embodiments of the invention.

The inventive clamping device for a cylinder liner of a piston or plunger pump is characterized in that on the piston or plunger pump a cylinder sleeve receptacle and a clamping element are provided and the cylinder liner or a part of the cylinder liner between the clamping element and the cylinder liner receptacle is arranged and the clamping element and the cylinder liner receptacle are connected to one another by connecting means, wherein the connecting means or the tensioning element have means for measuring or checking at least one expansion stress. With this device, it is advantageously possible to make the contact pressure of the sealing surface of the cylinder liner uniform and to measure during assembly and operation of the pump easily, reliably and quickly and without additional tools or measuring devices, the contact force or strain and thus to control.

A preferred clamping device is characterized in that the outer diameter of the cylinder liner or a part of the cylinder liner greater than the inner diameter of the cylinder liner receptacle and / or the clamping element is formed, whereby advantageously the use of existing or available liner or cylinder liners is possible. Furthermore, the handling is facilitated and the clamping device optimized in its design for use. As a rule, cylinder liners having an inner diameter of 3 to 10 inches, preferably 5 to 7.5 inches are used.

A further advantageous embodiment of the clamping device according to the invention provides that the clamping element as part of

Cylinder sleeve is formed. As a result, the handling during assembly or disassembly can be improved due to fewer parts.

A particularly preferred embodiment of the clamping device according to the invention is characterized in that a guide element for the cylinder liner is preferably arranged in the form of a sleeve on the clamping element, whereby the cylinder liner can be performed and handled better and easier during assembly and disassembly and against tilting but also better protected damage.

Another very advantageous clamping device according to the invention is characterized in that on the clamping element and / or the guide element and / or the cylinder liner at least one device for the installation and removal preferably a lifting eye is arranged. This is easier to handle, especially if the arrangement is tailored to the design of the device. The optimal vote of the arrangement of the installation and removal of the clamping element, the guide element and / or the cylinder liner is given when the lifting of the cylinder liner this is aligned approximately axially to the cylinder liner receptacle. A preferred clamping device is configured such that the cylinder liner receptacle is formed as part of the piston or Plungerpumpengehäuses or the valve block of the piston or plunger pump, whereby the advantage of an improved and simpler design is connected.

A further advantageous clamping device provides that the connecting means each consist of a fastener preferably a stud with an axially extending bore in the form of a shaft in which a measuring or control device is arranged, consisting of a over the end face of the fastener protruding measuring pin, which is preferably anchored at its inner end to the shaft and at the protruding end has a rotatable display element which is freely rotatable when the fastener is unloaded, but cooperates with the end face of the fastener under pressure and is secured against rotation, when the fastener is subjected to a predetermined tensile or tensile stress. By this preferred embodiment, no tool or additional measuring devices is necessary to perform a measurement and control of the strain or the contact pressure of the cylinder liner during assembly or operation of the mud pump.

A particularly advantageously designed clamping device is characterized in that at a measuring or control device, a further measuring or control device is arranged, consisting of a projecting beyond the end face of the first measuring pin second measuring pin, wherein the first measuring pin has an axially extending bore in the form of a shaft and wherein the second measuring pin is anchored at its inner end preferably on the shaft of the first measuring pin or the shaft of the fastener and at the protruding end a second rotatable display element which is freely rotatable when the fastener is unloaded, but with the face of the first Measuring pin or the first display element cooperates under pressure and is secured against rotation when the first measuring pin is subjected to a second predetermined tensile load, which is greater than the first predetermined tensile load or strain voltage. With this preferred clamping device, not only a certain minimum force but also a maximum force can be measured, which allows above all the control of the overuse of the clamping device or the cylinder liner. This makes it possible to control the first measuring device in addition to the control of all fasteners to uniform strain and thus contact pressure of the cylinder liner.

A preferred variant of the clamping device according to the invention provides that cylinder liners are used with the same outer diameter and different inner diameters, which advantageously the same clamping device for cylinder liners with different sized pistons or plungers and thus can be used in different performance areas of the mud pumps. In the respective cylinder liner, a piston or plunger is arranged, which is tuned to the inner diameter of the cylinder liner, cooperates with the cylinder liner and is connected to a drive.

In further advantageous embodiments of the clamping device according to the invention, a seal is arranged between the cylinder liner and the wear plate or between the cylinder liner the valve block. Thus, the seal of the cylinder liner and the flushing system is improved and optimized.

Also advantageous is the embodiment of the inventive clamping device, are arranged on the outside of the cylinder liner and / or inside in the cylinder liner receptacle indentations. The recesses facilitate the guidance during assembly and disassembly of the cylinder liners, because the friction surfaces are reduced while maintaining optimum guidance is still guaranteed.

The piston or plunger pump according to the invention for use as a flushing pump has at least one of the advantageous described above

Clamping devices for a cylinder liner on. Thus, the disadvantages of the flushing pumps are avoided according to the prior art and optimizes the transport of flushing of the type mentioned by lower cost, especially in the easier assembly and disassembly of the cylinder liners.

The inventive method for mounting a cylinder liner of a piston or plunger pump is characterized by the advantageous use of one of the described clamping devices, whereby a simpler and safer assembly is achieved.

embodiment

An embodiment of the invention is illustrated in the drawings and will be described in more detail below.

Show it

1 shows a clamping device of a cylinder liner as part of a flushing pump,

Figure 2 shows a clamping device of a cylinder liner of a flushing pump in

Oblique view and Figure 3, the clamping device together with a cylinder liner in section.

FIG. 1 shows a clamping device for a cylinder liner 5 as part of a rinsing pump. The front part of a flushing pump is shown in section, wherein 100 represents a flushing pump with the clamping device 5 according to the invention. Depending on the design, a rinsing pump can have several cylinder liners with the corresponding pistons or plungers. [0035] The pump housing 36 protrudes from the left into the cut and only partially illustrated pump housing 13. It consists of a crosshead rod 30, on which a baffle plate 35 is attached, which protects the underlying part of the pump from flushing outlet in a seal failure. To the crosshead rod 30, a connecting member 33 is attached via a wing clamp. Via a further wing clamp 34, the actual piston rod 36 is connected to the connecting member 33. At the front end of the actual piston 14 is attached via the piston nut 38. Link 33, wing clamp 34 and piston nut 38 are used for quick assembly and disassembly of the piston 14 and cylinder liner. 5

The cylinder liner 5 seals via its sealing surface 20 from the valve block 25. In the illustrated case, the sealing package is as follows: In front of the cylinder liner 5 and on its sealing surface 20, a seal 19 is arranged. This presses on a wear plate 17, which serves to prevent Ausspüler and damage from the valve block 25. The wear plate 17 also seals via a seal 18 to the actual valve block. The cylinder liner 5 is about the cylinder liner receptacle 2 and fasteners 3 against the

Sealing package pressed, whereby the required pressure on the sealing surface 20 and seal 18 must be applied. The device shown is shown enlarged in Figures 2 and 3 and described in more detail.

The piston 14 is placed on the crosshead rod 30 and the attached crank mechanism and the rotary drive device in a translational movement. By the back and forth movement of the piston 14 and the production of a pressure-tight space on the sealing surface 37 flushing is sucked in and expressed. The fluid is sucked in via the flushing flow 21 into the suction-side valve block 22 via the inner valve 23. In the forward stroke of this valve 23 closes again and the fluid is under pressure through the pressure-side valve 24 in the central Pressed pressure line 26, which connects all other cylinders not shown here among themselves. The fluid leaves at 27 the flushing pump.

The valve blocks 22 and 25 are interconnected and together via the screw 28 to the front panel 1 of the

Spülpumpegehäuses 13 screwed. The entire housing 13 is mounted on a stable frame or carriage 32

FIG. 2 shows a clamping device for cylinder liners of a rinsing pump. On the only partially illustrated front panel 1 of a

Pump housing 13 a rinsing pump cylinder liner receptacle 2 is attached. The cylinder sleeve receptacle 2 receives the front part of the liner or the cylinder liner 5 and forms together with the water part of the flushing pump a pressure chamber, which is designed in this embodiment for up to 350 bar operating pressure. At its rear end is the

Cylinder bushing 5 is guided by a clamping element 4, to which a further sleeve-shaped cylinder liner guide element 8 is connected on the pump side. This cylinder liner guide element 8 is fixedly connected to the clamping element 4. For easier and faster installation and removal of the cylinder liner 5, a lifting eye 6 is arranged at the upper part of the cylinder liner guide element 8, with which the clamping element 4 including the cylinder liner 5 therein lighter with the cylinder liner receptacle 2 and the valve block 25 or the front panel 1 of the pump housing can be connected. The lifting eye 6 can also be arranged on the clamping element 4 and advantageously serves as an assembly aid for the

Cylinder bushing 5. Particularly advantageous is the arrangement of the lifting eye 6 on the clamping element 4 or the cylinder liner guide element 8 such that the cylinder liner 5 is in the lifting position in approximately horizontal position to be inserted more easily and without tilting or damage in the cylinder liner receptacle 2. It is also possible to arrange a plurality of lifting eyes as an assembly aid on the clamping element 4 and / or the cylinder liner guide element 8. [0040] In the cylinder liner 5, the piston (not shown) suitable for this is guided axially. Depending on requirements, the inner diameter of the cylinder liner 5 may have different diameters. The outer diameter of the cylinder liner 5 corresponds in this embodiment, with the exception of a clamping shoulder 7, the inner diameter of the clamping element 4 and the cylinder liner guide element 8. In its front, the valve block 25 side facing the cylinder liner 5 in a partial region, the clamping shoulder 7, an outer diameter, the By means of the studs as fasteners 3 of the larger outer diameter portion of the cylinder liner 5 between the clamping element 4 and in this preferred embodiment, the cylinder liner guide element 8 on the one is greater than the inner diameter of the clamping element 4 and the cylinder liner guide element Side and the cylinder liner shots 2 firmly clamped on the other side. In this advantageous embodiment, four studs are used. However, it is also possible to use three or more than four connecting elements 3. The stud bolts are bolted to the cylinder liner receptacle 2. The fastening elements 3 and studs have on their side facing the cylinder liner receptacle 2 on a head 11 of the fastener 3, on whose end face 10 a measuring device 9 protrudes. The measuring device 9 is a device for measuring or checking at least one expansion stress. In particular, the strain measurement is used to control the contact pressure of the sealing surface of the cylinder liner 5 on the pressure-carrying element of the flushing pump as in this example, the wear plate 17 or the valve block 25. Such fasteners 3 with a torque or

Stress measuring device 9 on the head are usually referred to as Rotabolt. The part of the cylinder liner 5, which has a larger outer diameter than the rest of the cylinder liner 5 is referred to in this case as a clamping shoulder 7 of the cylinder liner 5. The clamping shoulder 7 is designed such that it is clamped tight and tight between cylinder sleeve receptacle 2 and clamping element 4.

Figure 3 illustrates the clamping device in cooperation with the cylinder liner in section. This is clearly visible as the cylinder liner 5 is pressed over the clamping shoulder 7 via the clamping element 4 against the valve block 25. The cylinder liner 5 and / or the cylinder liner receptacle 2 can, as shown in this example, indentations on the mating surface 15, which advantageously reduce the friction surface and allow easier guidance during installation and removal of the cylinder liner 5.

In order to create a pressure-tight space between the two elements valve block 25 and cylinder liner 5, the following arrangement of sealing elements is in this example. The cylinder liner 5 presses with the sealing surface 20 against the wear plate 17. The seal 19 is compressed.

The cylinder liner 5 is guided on one side in the sleeve 8 of the clamping element 4 and guided on the other side in the cylinder liner receptacle 2. This is connected via the screw 12 fixed to the valve block 25 and can be removed during disassembly on the Abdrückbohrungen 16.

Furthermore, the valve block 25 is connected via the screw 28 with the front panel 1 of the flushing pump. LIST OF REFERENCE NUMBERS

1. Front panel of the pump housing

2. Cylinder bush receptacle 3. Fastening element with measuring device

4. clamping element

5th cylinder liner

6. Lifting eye

7. Clamping shoulder of the cylinder liner 5 8. Guide element (sleeve shape)

9. Measuring device of the fastening element 3rd

10. face on the head 11 of the fastener. 3

11. Head of the fastening element 3

12.Crewing of cylinder liner receptacle 2 to valve block 25 13. Rinsing pump housing

14th piston

15. mating surface between cylinder liner 5 and receptacle 2

16. Abdrückbohrungen for cylinder liner receptacle 2

17. wear plate between cylinder liner 5 and valve block 25 18. sealing element between wear plate 17 and valve block 25th

19 sealing element between the cylinder liner 5 and wear plate 17th

20. Sealing surface of the cylinder liner 5 21. Spülungszufluss

22. Valve block (suction side) 23. Valve (suction side)

24. valve (pressure side)

25. Valve block (pressure side)

26. Central pressure line between the valve blocks 27. Pressure outlet 28. Screw connection from front plate 1 to valve block 25

29. Opening to the cylinder box chamber

30. Crosshead bar 31. Tool attachment shoulders for disassembly

32. Mounting frame for flushing pump

33. Link between crosshead rod 30 and piston rod 36th

34. wing clamp for connecting the connecting member 33 and the piston rod 36th

35. baffle plate for flushing outlet

36. Piston rod

37. Sealing surface of the piston 14 to the cylinder liner. 5

38. Piston nut 39. Valve cover

100. Rinse pump

Claims

claims 1. Clamping device for a cylinder liner of a piston or plunger pump, characterized in that on the piston or plunger pump Cylinder sleeve receptacle (2) and a clamping element (4) are provided and the cylinder liner (5) or a part of the cylinder liner (5) between the clamping element (4) and the cylinder liner receptacle (2) is arranged and the clamping element (4) and the cylinder liner receptacle ( 2) by connecting means (3) are interconnected, wherein the connecting means (3) or the clamping element (4) comprises means (9) for measuring or controlling at least one strain voltage. 2. Clamping device according to claim 1, characterized in that the outer diameter of the cylinder liner (5) or a part of the Cylinder sleeve (5) is greater than the inner diameter of the cylinder liner receptacle (2) and / or the clamping element (4) is formed. 3. Clamping device according to claim 1 or 2, characterized in that the clamping element (4) is formed as part of the cylinder liner (5). 4. Clamping device according to one of claims 1 to 3, characterized in that on the clamping element (4) a guide element (8) for the cylinder liner (5) is arranged. 5. Clamping device according to one of claims 1 to 4, characterized in that on the clamping element (4) and / or the guide element (8) and / or the cylinder liner (5) at least one device for the installation and removal preferably a lifting eye ( 6) is arranged. 6. Clamping device according to one of claims 1 to 5, characterized in that the cylinder liner receptacle is formed as part of the piston or Plungerpumpengehäuses (13) or the valve block (25) of the piston or plunger pump. 7. Clamping device according to one of claims 1 to 6, characterized in that the connecting means (3) each consist of a fastener preferably a stud with an axially extending bore in the form of a shaft, in which a measuring or control device (9) is consisting of a projecting beyond the end face (10) of the fastener measuring pin, which is preferably anchored at its inner end to the shaft and at the protruding end has a rotatable display element which is freely rotatable when the fastener is unloaded, but with the end face of the fastener cooperates under pressure and is secured against rotation when the fastener is subjected to a predetermined tensile stress or strain. 8. Clamping device according to one of claims 1 to 7, characterized in that on a measuring or control device (9), a further measuring or control device is arranged, consisting of a projecting beyond the end face of the first measuring pin second measuring pin, wherein the first measuring pin has an axially extending bore in the form of a shaft and wherein the second measuring pin preferably at its inner end on the shaft of the first measuring pin or the shaft of the Fastening element is anchored and has at the protruding end a second rotatable display element which is freely rotatable when the fastener is unloaded, but cooperates with the end face of the first measuring pin or the first display element under pressure and is secured against rotation when the first measuring pin a second predetermined tensile load is greater than the first predetermined tensile load or strain voltage is exposed. 9. Clamping device according to one of claims 1 to 8, characterized in that cylinder liners (5) are used with the same outer diameter and different inner diameters. 10. Clamping device according to one of claims 1 to 9, characterized in that in the cylinder liner (5) a piston (14) or plunger is arranged, which is matched to the inner diameter of the cylinder liner (5), with the cylinder liner (5) cooperates and connected to a drive. 11. Clamping device according to one of claims 1 to 10, characterized in that between the cylinder liner (5) and the wear plate (17) or the valve block (25) a seal (19) is arranged. 12. Clamping device according to one of claims 1 to 11, characterized in that on the outside of the cylinder liner (5) and / or inside in the cylinder liner receptacle (2) indentations are arranged. 13. Piston or plunger pump for use as a flushing pump with at least one clamping device for a cylinder liner (5) according to one of claims 1 to 12. 14. A method for mounting a cylinder liner of a piston or Plunger pump, characterized in that a clamping device according to one of claims 1 to 12 is used.