REDUCING DEVICE

Abstract: Reducing device for reducing the pressure of an infed fluid. The reducing device comprises a housing (1) with a pressure-regulating part (2) fixed thereto. According to the invention, a shutt-off part (4) is fitted on the same side. This makes the reducing device more readily accessible for maintenance work. A monitor part can also be fitted between the regulating part and the shutt-off part. This provides a particularly compact unit, which can even be installed underground.

Description: Reducing device. The present invention relates to a reducing device according to the preamble of Claim 1. Such a device is disclosed by German "Auslegeschrift" l,2l4,065. The latter discloses a reducing valve with safety device. Both the pressure-regulating part and the shut-off part are fitted at one side of the housing. The regulating part is fitted further away from the hous¬ ing than the shut-off part. Such reducing devices are used in, for example, the "medium pressure" part of distribution networks for natural gas. They generally comprise, a pressure-regulating part, a monitor part and a shut-off part. In this case the pressure-regulating part serves primarily to carry out the pressure-reducing function. If said pressure- regulating part fails, its function is taken over by the monitor part, which is set at a slightly higher pressure. If the monitor part fails, the shut-off part, which is set at an even higher pressure, goes into operation. In this case, however, the flow of gas is completely ' blocked. It was usual to place three valves with the corresponding functions in series one after the other. However, this took up a considerable amount of space, which constitutes a problem in particular in towns, where such reducing devices are commonly used. It is important for preventive main¬ tenance that such reducing devices should be readily accessible so that the various "soft" parts can be replaced in a simple way. This means that cabinets taking up a relatively large amount of space are always neces¬ sary, and in towns safety measures have to be taken to ensure that access by unauthorised people is prevented. In order to deal with these pro¬ blems, a reducing device in which regulating part and shut-off part are integral was proposed in the prior art. In this case the regulating part was fitted at one side of the housing, and the shut-off part at the other. Although in this way the overall length of the reducing device could be considerably reduced because only a monitor part now needed to be fitted alongside, the problems concerning accessibility remained. For, if one of the two parts is fitted facing upwards, sufficient space has to be available below it for the relevant preventive and other maintenance work on the other part at the bottom. The object of the present invention is to avoid these disadvantages. This object is achieved in the case of a reducing device of the type described above by the characterising measures of Claim 1. Surprisingly, it has been found that it is possible to place the regulating part and.the shut-off part at one side of the housing. For this, it is, however, necessary to design the regulating part with a sleeve which can accommodate the valve spindle which operates the shut- off part. It is now possible to fit the reducing device with the under- • side close to the bottom of the fitting space, because good accessibility at the bottom side is of minor importance. This means that the space taken up is reduced, while maintenance work is facilitated. In order further to reduce the size of the reducing device, which will always be combined with a monitor part, according to an advantageous embodiment of the invention this monitor part is fitted between the regulating part and the shut-off part. Although the dimen¬ sions of the construction are increased in height as a result, the over¬ all length is further reduced, while the number of flanges, and thus fragile connections, is limited. The design with a sleeve through which the valve spindle which is accommodated in the regulating part extends can be combined in a par¬ ticularly advantageous way with a ring diaphragm which provides the pres¬ sure regulation of the regulating part. According to a further advantageous embodiment in which the monitor part is placed between the shut-off part and the regulating part, said monitor part is also provided with a sleeve for accommodating there¬ in the valve spindle, the sleeve being connected to a diaphragm, and the end of the sleeve functioning as a seat face of a shut-o " ff valve. The seat face interacting therewith is preferably a part of the sleeve of the regulating part described above. The shut-off part preferably comprises a diaphragm-controlled release device for the valve spindle. This release device can be designed with a pressure sleeve which is provided with a constriction and is con¬ nected to the valve spindle, and which is accommodated in a rotary sleeve provided with recesses and a number of locking elements disposed between the rotary sleeve and the pressure sleeve. In this case the locking elements can comprise a sleeve provided with grooves and having a thickened edge. According to a further advantageous embodiment, the housing of the reducing device can be provided with filter means at the side away from the regulating part. The accommodation in a housing also means that a complete gas station which has such compact dimensions that it can be placed underground is provided, which is important particularly in towns and other densely populated areas. The invention will be explained in greater detail below with reference to examples of embodiments shown in the drawing, in which: Fig. 1 shows a first embodiment of the device according to the invention, in side view in cross-section; Fig. 2 shows- a cross-section along the line II-II from Fig. 1 of the device in the blocked position; Fig. 3 shows a cross-section corresponding to Fig. 2, in the open position of the device; and Fig. shows a further embodiment of the invention. The regulating/monitor/shut-off valve according to the present invention comprises a housing 1, a regulating part 2, a monitor part 3. and a shut-off part 4. The housing 1 is provided with connecting flanges 5 and 6, 5 being the inlet side and 6 the outlet side. Housing 1 contains an inlet bore 7 a d an outlet bore 8, and also a valve assembly consisting of a valve disc 9 with sealing 0-ring 10 and valve seat 11, which is formed by the end of sleeve 12. Valve disc 9 is disposed so that it is slidable between two positions on valve spindle 13. The travel upwards is limited by a spring-loaded ring 14, while the movement downwards is limited by an 0-ring 15. Valve disc 9 i the position shown in Fig. 1 is loaded by spring 16, which at the other side engages on cover 17, which is fixed to housing 1 by means of bolts 18. 0-ring 19 functions to seal the cover relative to the housing. A channel system 20 is accommodated in valve spindle 13- In the down position of the valve disc 9. as shown in the figure, a connection will be made here above and below the valve disc by this channel system 20 because the spring force of the spring-loaded ring 14 is lower than the spring force of spring 16, so that the ring 14 is pressed into the flat position. If, however, as will be explained later, the force of the spring 16 is directed to valve seat 11, and no upward force is exerted on valve spindle 13. i.e. if the valve disc is moved upwards under the influence of spring 16 and seals off with 0-ring 10 against valve seat 11, valve spindle 13 will be moved upwards relative to valve disc 9 by spring-loaded ring 14 in such a way that 0-ring 15 pro¬ vides for sealing with the valve disc, so that the channel system 20 no longer provides a connection between the top and bottom side of the valve disc. When a force is exerted on valve spindle 13 from that position, the spring action of spring-loaded ring 14 will first be overcome before there is any movement against the force of spring 16. In other words, a connection will first be produced between the top and bottom side of the valve disc, and only then will the valve disc be moved. Sleeve 12 is also provided at the other end with a valve seat 21, which is realized by 0-ring 22. A displaceable sleeve 23 engages on 0-ring 22. Said sleeve 23 forms part of the monitor part 3 of the device according to the invention. The regulating part 2 is provided with a seat ring 24 which is coupled to the sleeve 12 and on which a ring diaphragm 2 engages. The space behind the ring diaphragm 25 is connected by means of line 26 to a regulating unit 27. The outlet pressure of the device is supplied to regulating unit 27 through line 28. It is also possible to supply other variables such as the. inlet pressure of gas to it. In the normal working position sleeve 23 will be free from 0-ring 22, with the result that the gas can flow through sleeve 22 into chamber 30. Controlled by regulating unit 27, ring diaphragm 25 will rest more or less against seat ring 24 and in this way reduce the pressure of the ingoing gas and bring it to the desired pressure through outlet chamber 31 to outlet bore 8. Chamber 30 is provided with a connection 32 for con- * necting to the regulating unit 27- The monitor part 3 contains the sleeve 23 described above. In this sleeve 23 a bore 33 is present for taking the extension of valve spindle 13, indicated by 34. The valve spindle comprises two separate parts, in order to make simple dismantling possible. Sleeve 23 is, on the one hand, pressed downwards by spring 35. which engages on the top side of a diaphragm box 3 while, on the other hand, an upward directed force can be exerted on the sleeve 23 by the diaphragm 37 which lies in diaphragm box 3 and is connected to said sleeve. Diaphragm box 36 has two chambers separated by diaphragm 37. !•£• a top chamber 38 and a bottom chamber 39- Top chamber 38 s connected by means of line 42 to the outlet pressure of the valve. Bottom chamber 39 is connected by means of line 4l to a monitoring unit 40 which is connected, inter alia, by means of line 3 to the outlet pressure of the device. The outlet pressure is preferably measured downstream of the device by means of the lines 28, 42 and 43, in order to remove any turbulence effects due to the device according to the invention. Monitoring unit 4θ can also be provided with further control signals, such as the inlet pressure. Monitoring unit 40 is designed in such a way that it controls sleeve 23 so that the pressure of the gas present in chamber 30. > e « the pressure controlled by moni¬ toring unit 40, is slightly higher than the pressure present in outlet chamber 31. -e. the pressure controlled by regulating unit 27. This means that in the normal operating state, monitoring unit 3 essentially has no pressure-reducing effect. Shut-off unit 4 is shown not only in Fig. 1 but also in Figs. 2 and 3- It can be seen in particular from Fig. 2 that it comprises a diaphragm box 45 containing a diaphragm 46. Diaphragm box 45 is divided by diaphragm 46 into chambers 47 and 48. In this case the outlet pressure acts on chamber 47 through line 49, while chamber 48 is connected to atmospheric pressure. Connected to diaphragm 46 is a disc - 0 to which a rod 51 is attached, which in turn acts on a U-shaped part 5 . U-shaped part 52 is driven to the right in the drawing by means of rod 53 con¬ nected to plate 4 under the influence of spring 55• U-shaped part 5 contains a slot 56 in which a stop pin 57 is accommodated in such a way that it has limited movement. Stop pin 57 is connected to a rotary sleeve 58. Sleeve 58 has an essentially cylindrical inner periphery and is pro¬ vided with recesses 59 arranged along the periphery. A plastic sleeve 60 with a thickened top edge 61 is provided inside sleeve 58. The plastic sleeve 60 is divided at least at the thickened top edge by the presence of grooves 62. This means that plastic sleeve 60 can be seen as a ring with ball-type elements fixed to the ends by means of fingers. The extended valve spindle 3 is provided with an adjustable pressure pin 65. The latter acts on a pressure sleeve 66 which is provided with a bevelled and narrowed part. The diameter here is such that a thickened top edge 61 of plastic sleeve 60 can be accommodated in the space bounded between the narrowed part and sleeve 58. Pressure sleeve 66 is extended by an indicator rod 67 on which a push button 68 acts. An emergency stop but¬ ton 69 and a reset button 70, which can be seen in particular from Figs. 2 and 3. are also present. They act on sleeve 58. The shut-off part described above functions as follows: Starting from the position shown in Figs. 1 and 2, if the pres¬ sure at the outlet becomes too high, such excess pressure is communicated by means of line 49 to diaphragm 46. This causes rod 51 to slide to the left, and U-shaped part 2 will also move stop pin 57 to the left. As a result, sleeve 58 moves anticlockwise, as shown in Fig. 2, so that the parts of the thickened top edge 6l of plastic sleeve 60 come to lie in front of the recesses 59- Due to the force of spring 16 exerted by pres¬ sure sleeve 66 (by means of valve spindle 13. extended valve spindle 34 and adjustable pressure pin 65) . the pressure sleeve can move upwards along the thickened top edge 61 (see Fig. 3) • In this way provision is made for a seal between valve disc 9 and in particular the 0-ring thereof and valve seat 11. Indicator rod 67 in this case moves outwards together with push button 68, so that an indication is given that the device is shut off. If desired, means may engage on push button 68 for the purpose of giving an alarm. For putting the device into operation again, push button 68 must first be pressed. This exerts a force on valve spindle 13. with the result that a connection is provided at both sides of the valve disc by means of channel system 20. It is possible in this way to move valve disc 9 downwards, which would otherwise be difficult on account of the pressure difference existing between the inlet pressure and the many times lower outlet pressure. When there is further movement downwards, sleeve 8 must then be turned by.pressing reset button 70. In this way the thickened top edge 6l is pressed in again from the position shown in Fig. 3. so that the position shown in Figs. 1 and 2 is obtained. By pres¬ sing emergency stop 69 in the position shown in Figs. 1 and 2, sleeve 58 is immediately turned to the position shown in Fig. 3- The presence of slot 5 means that it is not necessary to move the U-shaped part _>2 for this. . The device according to the invention is equipped in such a way that the pressure at which shut-off ' part 4 becomes effective is higher than the pressure at which monitor part 3 becomes active, which pressure is in turn higher than the pressure at which the regulating unit 2 func- tions. This means that in normal operating conditions only regulating unit 2 will function. If regulating unit 2 fails for any reason, the monitoring unit 3 will take over the pressure control, albeit at a slightly higher pressure. If this part also no longer functions properly, shut-off part 4 will go into operation, but in this case operation of the device according to the invention is, of course, ended. Manual interven¬ tion is now necessary. For simple maintenance bolt construction 72 is present. By loosening this bolt construction it is possible to change the various "soft" parts of the device periodically or as required. The device according to the invention has the advantage that all regulating and monitoring parts are accommodated at only one side of housing 1, which facilitates maintenance and makes compact installation necessary. For maintenance, only loosening of the bolt construction 72 and removal of cover 17 are necessary, following which the device can be dismantled completely. The device shown here is particularly suitable for regulation of the pressure in gas networks, and in particular in the medium pressure range. In other words, the supply pressure lies between 3 an 8 atm, and the inlet pressure can be approximately 200 mm water column. The use of rotary sleeve 8 provides for a particularly low-friction and therefore a sensitive shut-off system. The use of plastic sleeve 60 with thickened top edge 6l eliminates the problem in the prior art of the balls falling off and being lost during maintenance work. Fig. 4 shows a further embodiment of the invention. In this case a different housing 75 is used, but the same parts 2, 3 and 4 are fitted on it. These parts are, however, now surrounded by a housing 76. The housing 75 is designed for the accommodation of a filter housing 77 inside which a filter 78 is disposed. Housing 75 is provided with a down¬ ward extension 79 on which a cover 80 is fitted. Spring 16 rests by means of a threaded part 8l on filter housing 77• An only diagrammatically shown inlet valve 82 with operating rod 83 is fitted in the inlet part 7 • The various regulating and monitoring parts are not shown in this drawing and correspond to the construction shown in Figs. 1 and 2. Filter housing 77 is provided with a dust blower 84 at the lower side. Connec¬ tion 85 is present for connecting thereto a pressure monitoring device. The device according to Fig. 4 operates in the same way as that of the earlier figures, but there is the possibility of blocking the supply of gas by means of inlet valve 82, while the gas introduced is filtered before it is reduced in pressure. The device according to Fig. 4 forms a complete gas station which can be accommodated without further measures in an existing distribution network. The particularly compact construc¬ tion thereof makes it possible to avoid separate housings and similar cabinets, and it is possible to place such a device underground, which can be of considerable importance particularly in cities where there is lack of space. Although the invention is described above with reference to a preferred embodiment, it must be understood that numerous modifications can be made to it without going beyond the scope of the present inven¬ tion. What is essential for the invention is the unique combination of regulating, monitoring and shut-off part lying at one side of the hous- ing. A complete underground gas station can be achieved with this com¬ bination.

Claims: CLAIMS 1. Reducing device for reducing the pressure of an infed fluid, comprising a housing (1) having fixed at one side thereof a pressure- regulating part (2) and a shut-off part (4) for operating by means of a spindle a .spring-loaded valve (9) for blocking the fluid flow through the housing (1) , characterised in that the regulating part (2) is fitted adjoining the housing (1) and comprises a sleeve (12) , while the shut-off part (4) is fitted adjoining the side of the regulating part (2) facing away from the housing (1) , and the spindle for operating the spring- loaded valve (9) comprises a valve spindle (13. 34, 65) connected to said valve (9) and guided axially through the sleeve (12) . 2. Reducing device according to Claim 1, in which a monitor part (3) is provided between the regulating part (2) and the shut-off part (4), which monitor part (3) comprises a regulating device with a higher regulating pressure than regulating part (2), while the monitor (3) is provided with a sleeve (23) for accommodation therein of the valve spindle (34, 65). 3. Reducing device according to one of the preceding claims, in which the regulating part comprises a ring diaphragm (25) connected to sleeve (12) , so as to form a seal with a seat face (24) . 4. Reducing device according to Claim 2 or 3. in which the sleeve of the monitor part is displaceable depending on the pressure, which sleeve (23) is provided near one end with a sealing face which can inter¬ act with a further sealing face in order to control the fluid supply to the regulating part (2) . 5- Reducing device according to Claim 4, in which said further sealing face comprises a-part (21) of * the sleeve (12) . 6. Reducing device according to one of the preceding claims, in which the shut-off part (4) comprises a diaphragm (46) and a controlled release device for the valve spindle (13-. 34, 65). 7. Reducing device according to Claim 6, in which the release device comprises a pressure sleeve (66) provided with a constriction, and connected to the valve spindle, and accommodated in a rotary sleeve (59) provided with recesses (59) and a number of locking elements provided between the rotary sleeve (59) and the pressure sleeve (66). 8. Reducing device according to Claim 7, in which the locking elements comprise a sleeve (60) provided with grooves (62) and having a thickened edge (6l) . 9. Reducing device according to one of the preceding claims, in which the housing (1) is provided with filter means (77, 78) at the side away from the regulating part (2) .

Inventors: STRAVER JOHANNES THEODORUS ANT, STRAVER, JOHANNES, THEODORUS, ANTONIUS
Applicants: STRAVER JOHANNES THEODORUS ANT, STRAVER, JOHANNES, THEODORUS, ANTONIUS
Application year: 1992
Main classification: G05D16
IPC codes: G05D16