JP2540614Y2 - Pre-cooling device for liquefied gas supply piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to an improvement of a precooling device for a liquefied gas supply pipe such as nitrogen, oxygen, and argon.

(Prior Art) As shown in FIG. 3, a conventional liquefied gas supply facility usually includes a liquefied gas storage facility 1 comprising a liquefied gas storage tank and a liquefied gas pressure vessel, a liquefied gas supply pipe 2, a precooling valve 3, and a use valve 4. , A precooled gas discharge pipe 5 and a liquefied gas use facility 6. In order to directly supply only the liquefied gas to the liquefied gas use facility 6 through the use source valve 4, the vaporized gas in the supply pipe 2 is discharged. At the same time, it is necessary to pre-cool the supply pipe 2 to a temperature close to the temperature of the liquefied gas to reduce the vaporization of the liquefied gas therein.

Therefore, when supplying the liquefied gas, first, the precooling valve 3 is opened with the use valve 4 closed, and the liquefied gas flows into the supply pipe 2 to exchange heat therewith, and the vaporized gas generated by the heat exchange While the supply pipe 2 is cooled while dispersing the gas to the outside through the discharge pipe 5, and the completion of the pre-cooling is performed from the adhesion of frost on the pre-cooled gas discharge pipe 5 without confirming that the released gas has changed from the vaporized gas to the liquefied gas. Assuming that the pre-cooling valve 3 was closed.

In addition, in the conventional liquefied gas supply equipment, the supply pipe 2 must be pre-cooled by manual operation every time the liquefied gas is supplied to the liquefied gas use equipment 6, requiring a lot of manpower and automation of the entire liquefied gas supply system. There was a disadvantage that it could not be measured.

(Problems to be Solved by the Invention) The present invention has the above-mentioned problems in the conventional liquefied gas supply equipment, that is, (a) the liquefied gas supply pipe must be manually precooled every time the liquefied gas is used, The reduction of the number of operating personnel cannot be measured, (b) the manual operation of the pre-cooling device makes it impossible to measure the systematic automation of the entire liquefied gas supply system, and (c) the change in the state of the pre-cooled gas discharge pipe etc. Since the completion of pre-cooling is determined, the determination tends to vary for each worker, and it is difficult to maintain the pre-cooling temperature of the supply pipe at a constant value. The present invention provides a liquefied gas supply pipe pre-cooling device that can automatically pre-cool liquefied gas to a certain temperature.

(Means for Solving the Problems) The present invention basically measures the temperature of the supply pipe directly or indirectly at the outlet side of the precooling valve, and automatically controls opening and closing of the precooling valve and the like based on the detected temperature. It is assumed that.

That is, the present invention includes an automatic opening / closing type pre-cooling valve 3 provided at the end of a liquefied gas supply pipe 2 communicating with a liquefied gas storage facility 1; a plurality of liquefied gas supply pipes 2 connected in parallel to the liquefied gas supply pipe 2. Liquefied gas supplied to the liquefied gas use equipment 6
A self-opening / closing valve 4 for controlling 11; a temperature sensor 7 provided in the liquefied gas supply pipe 2 in the vicinity of the precooling valve 3; a liquefied gas use request from the liquefied gas use facility 6 side When the signal 9 is input, a valve opening signal 13a is transmitted to the pre-cooling valve 3, and when the input temperature 14 from the temperature sensor 7 is lower than the set temperature, a valve closing signal 13b is transmitted to the pre-cooling valve 3 and to the original valve 4. Pre-cooling control device 8 that sends valve opening signal 15
And a precooling device for a liquefied gas supply pipe composed of:

(Operation) Liquefied gas use request signal 9 from liquefied gas use facility 6
Is input to the pre-cooling control device 8, the pre-cooling control device 8 outputs a valve opening signal 13a to the pre-cooling valve 3, and the pre-cooling valve 3 is opened. As a result, the liquefied gas flows in the supply pipe 2, cools the pipe 2, sequentially evaporates, and is discharged to the outside through the pre-cooled gas discharge pipe 5.

When the supply pipe 2 is cooled and the input temperature signal 14 from the temperature sensor 7 becomes equal to or lower than the set temperature, a valve opening signal 13b is transmitted from the precooling control device 8 to the precooling valve 3, and a valve opening signal is transmitted to the use source valve 4. 15 is transmitted, and the liquefied gas is supplied to the liquefied gas use equipment 6.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an overall system diagram of a precooling device for a liquefied gas supply pipe according to the present invention, and FIG. 2 is an operation explanatory diagram of the precooling device according to the present invention.

In the figure, 1 is a liquefied gas storage facility comprising a liquefied gas storage tank and a pressure vessel for nitrogen, oxygen, argon, etc., 2 is a liquefied gas supply pipe such as a vacuum insulated pipe, 3 is an ultra-low temperature solenoid valve or an ultra-low temperature pipe. An automatic opening / closing type pre-cooling valve composed of a pilot type control valve and the like, 4 is an automatic opening / closing type main valve composed of an ultra-low temperature solenoid valve attached to each of a plurality of branch pipes 2a branched and connected to the liquefied gas supply pipe 2, and 5 is A vaporization discharge pipe constituting an end portion of the liquefied gas supply pipe 2, a plurality of liquefied gas use facilities 6 connected in parallel to the liquefied gas supply pipe 2 via branch pipes 2 a, respectively, A temperature sensor provided near the outlet side, 8 is a control device equipped with relays, a programmable controller, etc., 9 is a liquefied gas use request signal transmitted from a liquefied gas use facility, 10 is a supply valve, and 11 is a liquefied gas. , 12 is the liquefied gas The released gas.

When the liquefied gas 11 is not used in the liquefied gas using equipment 6, the supply valve 10 is kept open at all times,
The pre-cooling valve 3 and the use source valve 4 are each maintained in a closed state.

Now, when the liquefied gas usage equipment 6 requires the liquefied gas 11, a liquefied gas usage request signal 9 is sent from various sensors or push buttons (not shown) provided on the liquefied gas usage equipment 6 side.
Is transmitted, and the signal 9 is input to the control device 8.

As shown in FIG. 2, the controller 8 first determines the presence or absence of a liquefied gas use request signal 9 (step A). When the input of the signal 9 is confirmed, a valve opening signal 13a is transmitted to the pre-cooling valve 3 and the valve is opened. Opening is performed (step B). This allows
The liquefied gas 11 flows from the liquefied gas storage facility 1 into the supply pipe 2, undergoes heat exchange with the pipe 2, evaporates, and is discharged to the outside as a discharge gas 12 (step C).

On the other hand, the temperature sensor 7 provided near the outlet side of the pre-cooling valve 3
As a result, the temperature of the supply pipe 2 (or the temperature of the released gas 12) is detected (Step D), and the detected temperature signal 14
Is input to the control device 8. The detected supply pipe 2
Is determined to be equal to or lower than a set temperature (for example, when the liquefied gas 11 is nitrogen gas, the set temperature is -150 ° C. to -190 ° C.) (step E). If the detected temperature is equal to or lower than the set temperature, a closing signal 13b is transmitted to the automatic opening / closing type pre-cooling valve 3 to be closed (step F), and a valve opening signal 15 indicating completion of pre-cooling is sent to the automatic opening / closing type use valve 4 (Step G). This allows
Liquefied gas use equipment 6 that has transmitted the liquefied gas use request signal 9
Liquefied gas 11 is supplied to the liquefied gas use equipment 6.

In this embodiment, a direct-acting ultra-low temperature solenoid valve is used as the automatic opening / closing type pre-cooling valve 3. However, when the supply pipe 2 has a large diameter exceeding 1 ″, the direct-acting electromagnetic valve is used. An air pressure control valve using a so-called pilot solenoid valve may be used instead of the valve.

(Effects of the Invention) In the present invention, the pre-cooling valve 3 is an automatic opening / closing type ultra-low temperature valve, and the pre-cooling valve 3 is opened according to a use request signal from the liquefied gas use equipment 6 side, and is disposed near the outlet thereof. The temperature sensor 7 detects the temperature of the supply pipe 2 during pre-cooling,
When the detected temperature of the supply pipe 2 becomes equal to or lower than the set value, the pre-cooling valve 3 is automatically closed and the use valve 4 is automatically opened via the pre-cooling control device 8.

As a result, the pre-cooling of the supply pipe 2 which has been performed manually every time the liquefied gas is supplied to the liquefied gas using equipment 6 can be automatically performed, thereby reducing the number of workers and improving the work efficiency.

Further, since the temperature of the supply pipe 2 during the pre-cooling is detected by the temperature sensor, the completion of the pre-cooling is more accurately determined as compared to a case where the pre-cooling completion is estimated from a change in the state of the release of the vaporized gas. Can be done.

Further, by automating the precooling operation, it is possible to automate the entire liquefied gas supply system.

As described above, the present invention has excellent practical utility.

[Brief description of the drawings]

FIG. 1 is an overall system diagram of a liquefied gas supply facility provided with a precooling device according to the present invention. FIG. 2 is an operation explanatory view of the precooling device according to the present invention. FIG. 3 is an overall system diagram of a conventional liquefied gas supply facility. DESCRIPTION OF SYMBOLS 1 ... Liquefied gas storage equipment 2 ... Supply pipe 3 ... Automatic opening / closing type precooling valve 4 ... Automatic opening / closing type use valve 5 ... Precooled gas discharge pipe 6 ... Liquefied gas use equipment 7 ... Temperature sensor 8 ... … Pre-cooling control device 9… Liquefied gas use request signal 10… Supply valve 11… Liquefied gas 12… Released gas 13 a… Pre-cooling valve open signal 13 b… Pre-cooling valve close signal 14… Input from temperature sensor Temperature signal 15 ... Used valve open signal

Claims (1)

(57) [Scope of request for utility model registration] An automatic opening / closing type precooling valve (3) provided at an end of a liquefied gas supply pipe (2) communicating with a liquefied gas storage facility (1); A self-opening / closing use source valve (4) for controlling a liquefied gas (11) to be supplied to each of a plurality of liquefied gas use facilities (6) connected in a line; and disposed near a pre-cooling valve (3). A temperature sensor (7) provided in the liquefied gas supply pipe (2); and a valve open signal (13) to the precooling valve (3) in response to the input of the liquefied gas use request signal (9) from the liquefied gas use facility (6).
a) is transmitted, and when the input temperature (14) from the temperature sensor (7) is lower than the set temperature, a valve closing signal (13b) is transmitted to the pre-cooling valve (3) and a valve is transmitted to the original valve (4). A precooling control device (8) for transmitting an open signal (15);