JP4930227B2 - Displacer recovery device for displacer level gauge - Google Patents

Description

  The present invention provides a displacer type liquid level gauge used for measuring the liquid level of a liquid stored in a storage tank. When a wire connected to a displacer is cut, the displacer with the cut wire is The present invention relates to a displacer recovery apparatus for a displacer type liquid level gauge used for recovery.

  As a type of liquid level gauge for measuring the liquid level (position of liquid level) in storage tanks for LNG (liquefied natural gas), LPG (liquefied petroleum gas), other liquefied gases, and various liquid storage tanks, Displacer level gauges are known.

  FIG. 3 shows an outline of an example of the displacer type liquid level gauge I. A guide cable (guide wire) 2 is stretched from the roof portion 1a to the floor portion 1b in the storage tank 1, and the guide cable 2 Further, a float (displacer) 3 floating on the surface of the storage liquid 4 is attached so as to be movable in the vertical direction. Further, a nozzle 5 is provided on the roof portion 1 a of the storage tank 1, and the length measuring wire 7 fed out from the drive portion 6 is guided into the storage tank 1 through the nozzle 5, and the lower end portion of the length measuring wire 7 is provided. The float 3 is attached so as to be suspended. Thereby, the vertical displacement of the float 3 floating on the liquid surface of the storage liquid 4 in the storage tank 1 is set to the feeding length of the length measuring wire 7 connected to the float 3 from the drive unit 6. By detecting based on this, the liquid level of the storage liquid 4 in the storage tank 1 can be measured. The lower end of the guide cable 2 is fixed to a weight 8 disposed on the floor 1b of the storage tank 1 via an anchor 9 (see, for example, Patent Document 1).

  Further, as another type of displacer type liquid level gauge, as schematically shown in FIG. 4, a balance driver 10 is provided above the roof portion 1a of the storage tank 1, and the balance driver 10 is not shown. A displacer 12 having a specific gravity greater than that of the storage liquid 4 in the storage tank 1 is attached to the lower end portion (tip end portion) of the length measuring wire 11 unwound from the wire drum and suspended in the storage tank 1. A form of this type is also known.

  In the case of the displacer type liquid level gauge I of this type, when the displacer 12 suspended from the length measuring wire 11 is partially immersed in the storage liquid 4 in the storage tank 1, the displacer 12 Since the buoyancy according to the volume of the portion immersed in the storage liquid 4 is applied, the tension acting on the length measuring wire 11 suspending the displacer 12 from the balance driving machine 10 causes the displacer 12 to be in the air. The state of being hung on the screen changes. Therefore, the length measuring wire 11 is unwound and wound by the balance driving device 10 in a state where the tension acting on the length measuring wire 11 is maintained so that the flooding of the displacer 12 is constant. Since the displacer 12 can be moved up and down precisely following the liquid level of the stored liquid 4, the displacer 12 is wound around the balance driving machine 10 when moving up and down following the liquid level of the stored liquid 4 in this way. The liquid level of the storage liquid 4 in the storage tank 1 can be measured on the basis of the length dimension of the measuring wire 11 that is put out.

  Further, in the displacer-type liquid level gauge I shown in FIG. 4, when the storage liquid 4 in the storage tank 1 undulates with the reception of the storage liquid 4 into the storage tank 1, the displacer 12 In order to be able to measure the liquid level of the storage liquid 4 while avoiding the influence, it extends in the vertical direction through the roof 1a of the storage tank 1 to the vicinity of the bottom of the storage tank 1, and A guide pipe 13 having guide holes 14 is provided at a required interval in the vertical direction, and the displacer 12 is arranged inside the guide pipe 13.

  A calibration chamber 15 having a maintenance manhole 16 is attached to the upper end of the guide pipe 13 via a full-bore gate valve 17, and the balance drive is performed on the flange 15 a at the upper end of the calibration chamber 15. The measuring wire 11 attached to the machine 10 and unwound from the balance driving machine 10 is connected to the displacer 12 disposed inside the guide pipe 13 through the calibration chamber 15 and the gate valve 17 (for example, Patent Document 2).

  By the way, in the displacer type liquid level gauge I as described above, if the length measuring wires 7 and 11 are cut due to an unexpected situation, the displacement of the float 3 and the displacer 12 cannot be detected. It becomes impossible to measure.

  Therefore, in the displacer type liquid level gauge I of the type provided with the guide cable 2 shown in FIG. 3, a disc-shaped recovery tool having a specific gravity larger than that of the stored liquid 4 is provided below the float 3 as shown in FIG. 18 is arranged so that the recovery tool 18 is attached to the guide cable 2 so as to be movable in the vertical direction. Further, the recovery tool 18 is attached to the roof portion 1a (see FIG. 3) of the storage tank 1 together with the drive unit 6. It is considered that a recovery wire 20 suspended from the recovery winch 19 provided on the outside of the float 3 is connected to the recovery tool 18 to constitute a recovery device. In FIG. 5, the storage tank is not shown. Reference numerals 15, 16, and 17 in FIG. 5 denote a calibration chamber, a maintenance manhole, and a gate valve similar to those shown in FIG.

  According to the recovery apparatus having such a configuration, when the recovery tool 18 is submerged in the bottom of the storage tank 1 in advance and the length measuring wire 7 connected to the float 3 is cut, the recovery winch 19 is recovered. The collection wire 20 is wound up by the above and the collection tool 18 is pulled up from the lower side of the float 3 along the guide cable 2, so that the float 3 is placed on the upper side of the collection tool 18 and the roof of the storage tank 1. It can be recovered by lifting up to the part 1a.

  In addition, since the LPG storage tank has a duty of opening inspection, an operation for emptying the LPG in the tank is performed every required period. On the other hand, LNG storage tanks are not subject to open inspection, and LNG is not corrosive. Therefore, LNG storage tanks usually store LNG for a long time once the operation is started. Will remain.

Japanese Utility Model Publication No. 5-17522 Japanese Utility Model Publication No. 7-20531

  However, in the displacer type level gauge I of the type having the guide pipe 13 as shown in FIG. 4, the displacer 12 sinks to the bottom of the guide pipe 13 when the length measuring wire 11 is cut due to an unexpected situation. However, in reality, no means has been proposed for collecting the displacer 12 that has sunk to the bottom of the guide pipe 13.

  In addition, a displacer type liquid level gauge I of the type provided with the guide pipe 13 as shown in FIG. 4 is provided in a storage tank that is periodically opened and inspected like the LPG storage tank 1. If the length measuring wire 11 is cut due to an unexpected situation, the displacer 12 with the length measuring wire 11 cut can be recovered from the bottom of the guide pipe 13 at the next opening inspection. Therefore, when the period until the next opening inspection is long, the displacer 12 that has been sunk by cutting the length measuring wire 11 is left at the bottom of the guide pipe 13 until the next opening inspection, and the length measuring wire is cut. By connecting 11 to the new displacer 12 as it is or after replacement, the function of the displacer type liquid level gauge I can be recovered and the operation can be continued.

  However, when the displacer type liquid level gauge I of the type provided with the guide pipe 13 as shown in FIG. If the measuring wire 11 is cut due to a situation, there will be no opportunity to collect the displacer 12 that sinks to the bottom of the guide pipe 13. Further, when the displacer 12 sinking to the bottom of the guide pipe 13 is left for a long period of time, a piece of the measuring wire 11 remaining on the displacer 12 side discharges LNG from the LNG storage tank. There is also a concern that the suction pump may be gradually sucked into the pump to cause a problem with the discharge pump.

  Therefore, it is desirable to provide a means for collecting the displacer 12 in the case of the displacer type liquid level gauge I having the guide pipe 13 as shown in FIG. It is becoming.

  The apparatus for recovering the float 3 of the displacer type liquid level gauge I shown in FIG. 5 requires a guide cable 2 for guiding the float (displacer) 3 and the recovery tool 18 to move in the vertical direction. In addition, it is necessary to install a recovery winch 19 for winding the recovery wire 20 connected to the recovery tool 18, so that the configuration of the displacer-type liquid level gauge I is complicated and large. Therefore, it is not preferable to employ it as a displacer recovery device in the displacer type liquid level gauge I of the type having the guide pipe 13 as shown in FIG.

  Therefore, the present invention can recover the displacer that sinks to the bottom of the guide pipe when the length measuring wire connected to the displacer in the displacer type level gauge equipped with the guide pipe is cut. Therefore, an object of the present invention is to provide a displacer recovery device for a displacer type liquid level gauge that does not cause an increase in the size of the displacer type liquid level gauge.

  In order to solve the above-mentioned problems, the present invention provides a guide pipe that extends through the roof of the storage tank and extends in the vertical direction in the storage tank, corresponding to claim 1, and is provided on the upper end side of the guide pipe. A displacer attached to the tip of the length measuring wire that is unwound from the attached balance driving device is placed inside the guide pipe with a constant amount of water on the liquid surface of the stored liquid based on the tension acting on the length measuring wire. The guide pipe of the displacer-type liquid level gauge is configured to measure the liquid level of the stored liquid in the storage tank based on the length dimension of the measuring wire that is unwound from the balance driving machine. A basket storage portion is provided on the lower end side to store the collection basket, and a temporary window is mounted on the upper end side of the guide pipe in place of the balance drive unit. And Ji, attached to the distal end portion of the wire feeding from the temporary winch, and provided comprising constituting a basket holding device which can be carried out and leaving the holding of the collecting basket.

  In addition, the diameter of the basket storage portion in the above configuration is set to be equal to or smaller than the diameter of the roof penetration portion of the storage tank at the upper end portion of the guide pipe.

  Further, in the guide pipe of the displacer type level gauge in the above configuration, the diameter of the roof penetration portion of the storage tank at the upper end portion of the guide pipe is smaller than the diameter of the portion located in the storage tank of the guide pipe. The basket storage portion is provided on the lower end side of the guide pipe with a reducer interposed.

  The displacer-type liquid level gauge in each of the above-described configurations is provided with a gate valve on the upper end side of the guide pipe and a calibration chamber with a maintenance manhole, and a balance driving machine is provided on the flange on the upper end side of the calibration chamber. The temporary winch is attached to the flange on the upper end side of the calibration chamber.

According to the displacer recovery device of the displacer type liquid level gauge of the present invention, the following excellent effects are exhibited.
(1) A guide pipe that passes through the roof of the storage tank and extends in the vertical direction in the storage tank is provided, and is attached to the tip of a length measuring wire that is unwound from a balance drive attached to the upper end of the guide pipe. The length of the length measuring wire unwound from the balance driving machine when the displacer is placed inside the guide pipe with a constant amount of water on the surface of the stored liquid based on the tension acting on the length measuring wire. Based on the size, the basket storage section is provided on the lower end side of the guide pipe in the displacer type liquid level gauge that measures the liquid level of the storage liquid in the storage tank, and the collection basket is stored. Furthermore, a temporary winch for attaching to the upper end side of the guide pipe instead of the balance driving machine, and a tip of a wire fed out from the temporary winch In the case where the measuring wire is cut due to unforeseen circumstances, it has a configuration comprising a basket holding device that can hold and remove the collection basket. The sinking displacer can be received by the collection basket housed in the basket housing portion provided at the bottom of the guide pipe. Therefore, after a temporary winch is attached to the upper end side of the guide pipe instead of the balance driving machine, the wire is drawn out by the temporary winch to suspend the basket holding device to the position of the recovery basket, and the recovery basket After that, the collection basket is lifted up to the upper end of the guide pipe by winding the wire with a temporary winch, and the displacer with the length measuring wire received in the collection basket is collected. can do.
(2) The recovery of the displacer with the cut length measuring wire can be carried out in a state where the stored liquid is stored without emptying the stored liquid in the storage tank.
(3) During the normal operation of the displacer type liquid level gauge, it is only necessary to keep the collection basket stored in the basket storage part provided on the lower end side of the guide pipe. It does not become complicated or large. Moreover, since the temporary winch and the basket holding device are not used until the length measurement wire breaks, it is not necessary to prepare the temporary winch and the basket holding device between the storage tanks adopting the displacer recovery device having the above configuration. The winch and basket holding device can be rotated. Accordingly, the number of temporary winches and basket holding devices can be greatly reduced as compared with the number of storage tanks that employ the displacer collection device, so that the displacer occupies the introduction cost of the displacer level gauge. The cost ratio of the recovery device can be greatly reduced.
(4) By making the diameter of the basket storage part the same as the diameter of the roof penetration part of the storage tank at the upper end of the guide pipe, or by making the diameter smaller than the diameter of the roof penetration part, The collection basket stored in the basket storage section can be surely passed through the roof penetrating portion of the guide pipe, and the displacer with the length measurement wire cut can be reliably recovered.
(5) The guide pipe of the displacer type level gauge is configured such that the diameter of the roof penetration portion of the storage tank at the upper end of the guide pipe is smaller than the diameter of the portion of the guide pipe located in the storage tank. In addition, since the basket storage portion is provided on the lower end side of the guide pipe with a reducer interposed, the displacer with the length measuring wire cut in the guide pipe can be Even if the position shifted from the axial center sinks, by guiding by the reducer, the guide pipe has a lower end side that is equal to the diameter of the roof penetration part of the storage tank at the upper end of the guide pipe, or the roof The collection basket inside the basket storage part provided so as to have a diameter smaller than the diameter of the penetrating part securely receives the sinking displacer. It is possible.
(6) A displacer type level gauge is provided with a gate valve on the upper end side of the guide pipe and a calibration chamber with a maintenance manhole, and a balance driver is attached to the flange on the upper end side of the calibration chamber. And the temporary winch can be attached to the flange on the upper end side of the calibration chamber so that the balance drive unit and the temporary winch for the flange on the upper end side of the calibration chamber By closing the gate valve when attaching and detaching and when opening and closing the maintenance manhole, the calibration chamber can be separated from the internal atmosphere of the storage tank. And flammable storage liquids There may be as advantageous when applied to a storage tank for storing the storage liquid to be prevented from leaking to the environment.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIGS. 1 (a), (b) and FIG. 2 show the same configuration as shown in FIG. 4 in the storage tank 1 of the LNG 4a as the storage liquid as one embodiment of the displacer recovery device of the displacer type liquid level gauge of the present invention. As shown below, the present invention is applied to a displacer-type liquid level gauge I having a certain guide pipe 13 as follows. That is, a basket storage portion 21 is provided at the lower end of the guide pipe 13, and the collection basket 22 of the displacer 12 is stored in the basket storage portion 21. Further, a temporary winch 23 for attaching to the flange 15a at the upper end of the calibration chamber 15 in place of the balance driving machine 10 and a tip of a wire 24 fed out from the temporary winch 23 are attached to the recovery basket 22. A displacer recovery device is configured by including a basket holding device 25 that can switch between holding and releasing.

  More specifically, the guide pipe 13 sets a relatively small diameter portion 13a (hereinafter referred to as a roof penetration portion) 13a that penetrates the roof portion 1a of the storage tank 1 at the upper end portion, The located portion 13b is set to have a larger diameter than the roof penetrating portion 13a. Thereby, in the roof penetration part 13a of the said guide pipe 13, while being able to suppress the heat input into the storage tank 1 from the outside, the gate valve 17 connected to the upper side of this roof penetration part 13a is calibrated. It can be made small. Further, in the portion of the guide pipe 13 located in the storage tank 1, the displacer 12 that moves up and down following the liquid level of the LNG 4 a inside the guide pipe 13 may interfere with the guide pipe 13. It can be reduced.

  In addition, between the roof penetration part 13a in the said guide pipe 13 and the part 13b located in the storage tank 1, the taper part 13c gradually diameter-expanded toward the lower end side is provided by interposing. The vertical step is not formed on the peripheral wall surface of the guide pipe 13.

  Further, at the lower end side of the guide pipe 13, a basket storage portion 21 having the same diameter as the roof penetrating portion 13 a or a slightly smaller diameter and a depth corresponding to the height of the collection basket 22. However, they are integrally provided via the reducer 26. The basket storage portion 21 includes, for example, a cross-shaped bottom portion 21a at the lower end portion, and can hold the collection basket 22 in the basket storage portion 21 while being inserted from above.

  As shown in FIG. 2, the collection basket 22 has an outer diameter corresponding to the inner diameter of the basket storage portion 21 and a lower end portion of a cylindrical side wall 22a having a required height dimension in the vertical direction. A structure that allows the LNG 4a to pass therethrough, for example, a configuration in which a mesh-like bottom 22b is attached. Furthermore, the upper end of the side wall 22a of the collection basket 22 is provided with a folded portion 22c that is folded inward at an acute angle over the entire circumference, and the basket holding device 25 will be described later on the folded portion 22c. The hook 25a can be engaged from below.

  As shown in FIG. 1B, the temporary winch 23 has a flange 23a similar to the flange at the lower end of the balance driving machine 10 at the lower end. Thereby, after the balance driving machine 10 is removed from the flange 15a at the upper end of the calibration chamber 15, the flange 23a of the temporary winch 23 can be detachably bolted to the upper side of the flange 15a. It is. The temporary winch 23 can feed the wire 24 toward the inside of the calibration chamber 15 through the flanges 23a and 15a in a state where the temporary air winch 23 is attached to the upper side of the calibration chamber 15 and the outside air is shut off. It shall be like that.

  The basket holding device 25 collects the hooks 25a closer to the center by remote control from the temporary winch 23 side so that the basket holding device 25 can pass through the inside of the folded portion 22c of the collection basket 22. The state in which the hook 25a extends in the outer peripheral direction and is locked below the folded portion 22c of the collection basket 22 can be freely switched.

  Specifically, for example, as shown in FIG. 2, the basket holding device 25 is provided at circumferentially equidistant locations (three locations at intervals of 120 degrees in the figure) at the lower end portion of the cylindrical member 25b extending in the vertical direction as required. The upper end portion which is the base end portion of the hook 25a is attached so as to be swingable in the radial direction. Further, two wires 24a and 24b can be fed out from the temporary winch 23, and one of the wires 24a is connected to the upper end of the cylindrical member 25b. Further, the other wire 24b fed out from the temporary winch 23 is connected to a ring member 25c loosely fitted to the lower end portion of the one wire 24a, and the ring member 25c and the intermediate portion in the longitudinal direction of each hook 25a. Are connected via a hook pulling wire 25d. As a result, by loosening the other wire 24b of the two wires 24a and 24b fed out from the temporary winch 23, with the tension applied only to the one wire 24a, as shown by a solid line in FIG. When the hooks 25a of the basket holding device 25 are pulled down below the cylindrical member 25b by their own weights, that is, the hooks 25a are gathered closer to the center and the overall outer diameter of the basket holding device 25 is determined. It can be set to be smaller than the inner diameter of the folded portion 22c. On the other hand, by applying tension to the other wire 24b with the one wire 24a somewhat loosened, as shown by a two-dot chain line in FIG. 2, the ring member 25c and each hook pulling wire 25d are interposed. The hooks 25a are pulled up so that the hooks 25a can be projected to the outer peripheral side of the cylindrical member 25b up to a position having a diameter larger than the inner diameter of the folded portion 22c of the collection basket 22.

  Therefore, after the basket holding device 25 is suspended to the inside of the collection basket 22 with the tension applied only to the one wire 24a, the other wire 24b is wound up by the temporary winch 23 to By setting the tension to the other wire 24b rather than the other wire 24a, the hooks 25a can be protruded in the outer peripheral direction inside the collection basket 22. Therefore, after that, the other wire 24b is continuously wound in a tensioned state so that the tip end portion of each hook 25a is a folded portion 22c provided at the upper end portion of the side wall 22a of the collection basket 22. Thus, the collection basket 22 held via the hooks 25a can be lifted from the basket storage portion 21.

  Furthermore, the collection basket 22 held in the basket holding device 25 via the hooks 25a by applying tension only to the other wire 24b as described above is required by feeding the other wire 24b. When the one wire 24a is wound up after being placed at a location so that tension is applied only to the one wire 24a, the hooks 25a of the basket holding device 25 are gathered closer to the center. Thus, the basket holding device 25 can be detached from the collection basket 22.

  Reference numeral 27 denotes a purge gas supply line to the calibration chamber 15, and 28 denotes a gas discharge line of the calibration chamber 15. The maintenance manhole 16 of the calibration chamber 15 is opened, or the flange at the upper end of the calibration chamber 15 is opened. When removing the balance driving machine 10 or the temporary winch 23 from 15a, the gate valve 17 is closed and the calibration chamber 15 is separated from the atmosphere inside the storage tank 1, and then the calibration chamber 15 is filled. The LNG 4a vaporized gas can be purged to the gas discharge line 28 by a purge gas 29 such as nitrogen gas supplied from the purge gas supply line 27.

  In view of the fact that the stored liquid in the storage tank 1 is LNG 4a having a cryogenic temperature of −162 ° C., the basket storage portion 21, the collection basket 22, the wires 24 (24a, 24b), the basket holding device 25, etc. The members in contact with the LNG 4a are all made of stainless steel. Other components that are the same as those shown in FIG.

  When using the displacer collecting device of the displacer type liquid level gauge having the above configuration, the collecting basket 22 is stored in the basket storing portion 21 on the lower end side of the guide pipe 13 in advance as shown in FIG. Leave it in a state of letting it go. Further, the balance driving machine 10 is attached to the upper side of the calibration chamber 15, and in this state, like the displacer-type liquid level gauge I shown in FIG. The liquid level of the LNG 4a in the storage tank 1 is measured based on the amount of unwinding from the balance driving machine 10 of the measuring wire 11 connected to the displacer 12 arranged on the liquid surface with constant flooding. .

  When operating the displacer type liquid level gauge I as described above, if the length measuring wire 11 is cut due to an unexpected situation, the displacer 12 sinks in the guide pipe 13 and the guide pipe 13 is accommodated inside the collection basket 22 housed in the basket housing portion 21 on the lower end side. At this time, since the reducer 26 is provided between the lower end portion of the guide pipe 13 and the basket storage portion 21, the displacer 12 sinks even if it is out of the axial center in the guide pipe 13. Even in this case, the sinking displacer 12 is guided by the reducer 26 so that the displacer 12 is reliably guided to the collection basket 22 inside the basket storage portion 21.

  On the other hand, when the length measuring wire 11 is cut as described above, the tension due to the weight of the displacer 12 does not act on the length measuring wire 11 unwound from the balance driving machine 10, so that the tension is reduced. The cutting of the length measuring wire 11 is easily detected.

  When the cutting of the length measuring wire 11 is detected in this way, first, all the length measuring wires 11 unwound from the balance driving machine 10 are wound up to the balance driving machine 10 side.

  Next, after the gate valve 17 is closed, the vaporized gas of the LNG 4a filled in the calibration chamber 15 is purged, and then the balance driver 10 is fed from the flange 15a at the upper end of the calibration chamber 15. Remove.

  Next, a temporary winch 23 having a basket holding device 25 attached to the wire 24 (24a, 24b) is attached to the flange 15a at the upper end of the calibration chamber 15, and the gate valve 17 is opened. The wire 24 (24a, 24b) is unwound from the temporary winch 23, and the basket holding device 25 is lowered to the inside of the collection basket 22 at the lower end of the guide pipe 13.

  After that, as indicated by a two-dot chain line in FIG. 2, each hook 25 a of the basket holding device 25 is locked to the folded portion 22 c of the collection basket 22, and then the temporary winch 23 is used to By winding up 24 (24a, 24b), the said recovery basket 22 is lifted in the state which accommodated the displacer 12 from which the said measuring wire 11 was cut | disconnected.

  When the lifting recovery basket 22 reaches the inside of the calibration chamber 15, the temporary winch 23 is stopped, the gate valve 17 is closed, and then the LNG 4 a vaporized gas in the calibration chamber 15 is purged. Then, the maintenance manhole 16 is opened, and the displacer 12 with the cut length measuring wire 11 accommodated in the suspended collection basket 22 is collected.

  After the collection of the displacer 12 is completed, the maintenance manhole 16 is closed, the gate valve 17 is opened, the wire 24 (24a, 24b) is unwound from the temporary winch 23, and the basket holding device is The collection basket 22 held at 25 is suspended to the basket storage unit 21.

  After the collection basket 22 is again stored in the basket storage portion 21 as described above, the basket holding device 25 is detached from the collection basket, and then the wire 24 (24a, 24b) by the temporary winch 23 is used. Is lifted up to the inside of the calibration chamber 15.

  Thereafter, the gate valve 17 is closed, and then the LNG 4a vaporized gas in the calibration chamber 15 is purged. Thereafter, the temporary winch 23 attached to the flange 15a on the upper end side of the calibration chamber 15 is measured. By replacing the displacer 12 with the displacer 12 connected to the distal end side of the long wire 11, the displacer type liquid level gauge I whose function has been recovered is formed.

  As described above, according to the displacer recovery device for a displacer type liquid level gauge of the present invention, the displacer type liquid level gauge I of the type provided with the guide pipe 13 on the outer periphery of the displacer 12 makes it possible to measure the length of the wire. When 11 is cut, the displacer 12 that sinks can be recovered in a state where the LNG 4a is stored without emptying the LNG 4a in the storage tank 1. Moreover, during normal operation of the displacer-type liquid level gauge I, the displacer-type liquid level only has to be disposed by storing the collection basket 22 in the basket storage portion 21 provided on the lower end side of the guide pipe 13. The total I equipment configuration does not become complicated or large.

  Furthermore, since the temporary winch 23 and the basket holding device 25 are not used until a situation where the length measuring wire 11 is broken, it is not necessary to keep the temporary measuring winch 23 and the basket holding device 25. In the case of the tank 1, the temporary winch 23 and the basket holding device 25 can be reused. Accordingly, the number of the temporary winches 23 and the basket holding devices 25 can be greatly reduced as compared with the number of the storage tanks 1 adopting the displacer recovery device. It can be expected that the ratio of the displacer recovery device in the area will be greatly reduced.

  The present invention is not limited to the above embodiment, and the sizes of the displacer 12, the guide pipe 13, the basket storage portion 21, and the collection basket 22 are convenient sizes for illustration. You may change suitably according to the size of the actual storage tank 1, and the property of the liquid to store. Moreover, materials other than stainless steel may be employed as the material of each of the above members depending on the properties of the liquid to be stored.

  The displacer recovery apparatus of the present invention is suitable for use as a displacer recovery apparatus when a displacer-type liquid level gauge having a guide pipe 13 is installed in the storage tank 1 of the LNG 4a, but any other liquid can be used. You may apply to the displacer type liquid level gauge I installed in the storage tank 1 to store.

  The basket holding device 25 may adopt any basket holding means other than the hook 25a that operates in the direction of diameter expansion or diameter reduction, as long as it can switch between holding and releasing the collection basket 22 by remote control. Good. In this connection, the collection basket 22 may be of a type other than the type provided with the folded portion 22c as long as it can be held and detached by the basket holding means.

  The collection basket 22 can pass a storage liquid such as LNG 4a so as not to cause a large resistance when it is lifted or hung while held in the basket holding device 25, and the length measuring wire 11 is cut. If the length of the length measuring wire 11 attached to the displacer 12 that sinks into the collection basket 22 sometimes does not pass easily, the bottom 22b may have a structure other than a mesh such as punching metal. Further, the side wall 22a may have the same structure as the bottom 22b.

  Of course, various modifications can be made without departing from the scope of the present invention.

1 shows an embodiment of a displacer recovery device for a displacer type liquid level gauge according to the present invention. (A) shows a normal operation state of the displacer liquid level gauge, and (b) shows a state where the displacer is recovered. FIG. FIG. 2 is an enlarged cutaway side view showing a collection basket and a basket holding device in the apparatus of FIG. 1. It is a side view which shows the outline of an example of the displacer type liquid level gauge used conventionally. It is a partially cut schematic side view which shows the displacer type liquid level gauge of the type provided with the guide pipe used conventionally. FIG. 4 is a schematic diagram showing an apparatus considered for recovering the displacer of the displacer type liquid level gauge of FIG. 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Storage tank 1a Roof part 4 Storage liquid 4a LNG (storage liquid)
DESCRIPTION OF SYMBOLS 10 Balance drive machine 11 Measuring wire 12 Displacer 13 Guide pipe 13a Roof penetration part 13b Part located in a storage tank 15a Flange 16 Maintenance manhole 17 Gate valve 21 Basket accommodating part 22 Collection basket 23 Temporary winch 24, 24a, 24b Wire 25 Basket holding device 26 Reducer

Claims (4)

  A displacer attached to the distal end portion of the measuring wire that is provided through a roof of the storage tank and extends in the vertical direction in the storage tank, and is unwound from a balance drive attached to the upper end side of the guide pipe, On the inner side of the guide pipe, the length of the measuring wire from the balance driving device when the measuring wire is placed on the liquid surface of the stored liquid with a constant flooding based on the tension acting on the measuring wire. Based on the lower end side of the guide pipe in the displacer type liquid level gauge that measures the liquid level of the storage liquid in the storage tank, a basket storage portion is provided to store the collection basket, A temporary winch to be attached to the upper end of the guide pipe instead of the balance drive unit, and a wire attached from the temporary winch. Te, displacer recovery apparatus of the displacer type level gauge, characterized in that it has a provided comprising constituting a basket holding device which can be carried out and leaving the holding of the collecting basket.   2. The displacer type liquid surface according to claim 1, wherein the diameter of the basket storage portion is equal to or smaller than the diameter of the roof penetration portion of the storage tank at the upper end portion of the guide pipe. Total displacer collection device.   The guide pipe of the displacer type level gauge is configured such that the diameter of the roof penetration portion of the storage tank at the upper end of the guide pipe is smaller than the diameter of the portion of the guide pipe located in the storage tank, and 3. The displacer recovery device for a displacer type liquid level gauge according to claim 2, wherein a basket storage portion is provided on the lower end side of the guide pipe with a reducer interposed.   The displacer-type liquid level gauge has a configuration in which a gate valve and a calibration chamber with a maintenance manhole are provided on the upper end side of the guide pipe, and a balance driver is attached to the flange on the upper end side of the calibration chamber. 4. The displacer recovery device for a displacer type liquid level gauge according to claim 1, wherein the temporary winch can be attached to a flange on an upper end side of the calibration chamber.

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