JPS587164B2 - Maintenance, inspection and repair methods for capacitive liquid level gauges - Google Patents

Description

Detailed Description of the Invention: This application is intended to stop the operation of storage tanks and containers during maintenance, inspection, repair, etc. of capacitance type liquid level gauges that measure the liquid level in storage tanks and containers, and devices of similar structure. This invention relates to a method for maintenance, inspection and repair of a capacitance type liquid level gauge that allows replacement without having to do so.

The purpose of this application is to provide partition plates such as fins on the hanger to create several stages of small chambers in the guide pipe, and as the hanger is pulled up, the dangerous gas in the upper chamber is supplied with inert gas from the supply port. In addition, most of this dangerous gas is returned to the storage tank or container through the gas outlet to prevent it from being discharged to the outside. The distance between the gas outlet and the fins is set slightly smaller than the fin mounting interval to ensure efficient gas replacement, and the distance between the supply port and the flange surface is set longer than the fin mounting interval to ensure an inert gas seal. To provide a method for maintenance, inspection and repair of a capacitance type liquid level gauge, which allows continuous maintenance of liquid level.

Now, to explain one embodiment, a vertically elongated guide pipe 2 is installed in a part of a storage tank or container 1 up to the bottom of the storage tank or container 1, and a number of guide pipes that slide almost closely inside the guide pipe 2 are installed. A hanger 4 having gauges with fins 3 attached at regular intervals is attached to the guide pipe 2, and the guide pipe 2
Several stages of chambers 5 partitioned by fins 3 are formed inside, and an inert gas supply port 6 is opened in the guide pipe 2 near the lower end of the uppermost chamber 5a, and near the lower end of the second stage chamber 5b. At this point, a lower discharge port 7 is opened in the guide pipe 2.

The distance 1' between the supply port 6 and the lower discharge port 7 is made slightly smaller than the mounting distance 1 between the fins 3.

Reference numeral 8 denotes a bellows for airtightly holding the guide pipe 2 and the storage tank or container 1, and the supply port 6 has an inert gas conduit 9.
are connected, the gas conduit 9 extends upward along the side of the guide pipe 2, protrudes to the outside of the bellows 8, and connects to the main valve 10.
is provided.

Further, a gas upper discharge port 11 is provided near the upper end of the uppermost chamber 5a of the guide pipe 2, and the upper gas discharge port 1
1 is provided with a conduit 12, and the conduit 12 is provided with a main valve 13.

The hanger 4 is fixed to the flange 2a at the upper end of the guide pipe 2 by a support plate 14, and by making the space between the supply port 6 and the flange 2a longer than the mounting interval of the fins 3, a seal with inert gas is continuously maintained. It was designed so that

Reference numeral 15 denotes a meter which is attached to the flange 2a of the guide pipe 2 with bolts.

The operation of the present invention will be explained with reference to FIGS. 3A, 3B, and 3 based on the above structure. The main valve 10 is opened to supply inert gas.

Next, the main valve 13 is opened to discharge the hazardous gas in the uppermost chamber 5a partitioned by the fins 3a and 3b.

When the inside of the chamber 5a is sufficiently filled with inert gas, the main valve 13 is closed.

Remove the meter mounting bolt on the flange 2a and pull up the meter 15.

As a result, the fin 3b is shifted to the upper side of the supply port 6, so that inert gas is supplied to the second stage chamber 5b, and the dangerous gas in the chamber 5b is discharged from the lower discharge port 7 into the storage tank or container 1. 5b is filled with inert gas.

When the instrument 15 is further pulled up, the fin 3c is located above the lower discharge port 7, and since inert gas is continuously supplied, the storage tank and the outside air are sealed by the chamber 5b, preventing the discharge of dangerous gas and allowing safe work. .

Thereafter, using the same working principle, up to the chamber 5d partitioned by the fins 3d and 3e is replaced one after another, thereby preventing the discharge of dangerous gas and allowing safe work.

As described above, the present application is to install a hanger with a gauge having a number of fins attached at regular intervals inside the guide pipe, which slide almost closely inside the guide pipe, and to install a number of chambers partitioned by fins inside the guide pipe. An inert gas supply port is opened in the guide pipe near the lower end of the uppermost chamber, a lower discharge port is opened in the guide pipe near the lower end of the second chamber, and the upper end of the uppermost chamber is formed in stages. An upper discharge port is provided in the guide pipe near the section, and while supplying inert gas from the supply port, a small amount of dangerous gas only in the top chamber is discharged from the top discharge port, making the inside of the top chamber inert gas. After replacing the gas, pull up the hanger a little to open the supply port to the second chamber, supply inert gas into the second chamber, and discharge the dangerous gas into the tank from the lower discharge port to open the second chamber. After replacing the inside of the guide pipe with inert gas, the process of replacing the chamber one level below the top chamber in the guide pipe with inert gas is repeated, and the hanger is pulled up for maintenance, inspection, and repair. It is possible to achieve the purpose of the term.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the entire storage tank or container, FIG. 2 is an enlarged sectional view of the main parts, and FIGS.

Claims (1)

[Claims] 1. A hanger with a gauge having a number of fins attached at regular intervals that slide almost closely inside the guide pipe is installed inside the guide pipe, and several stages of chambers partitioned by fins are formed inside the guide pipe, and the top stage is An inert gas supply port is opened in the guide pipe near the bottom end of the chamber of the second stage, a lower discharge port is opened in the guide pipe near the bottom end of the second stage chamber, and a guide pipe is opened near the top end of the top stage chamber. An upper exhaust port is provided on the pipe, and while supplying inert gas from the supply port, a small amount of dangerous gas only in the top chamber is discharged from the upper exhaust port, and the inside of the uppermost chamber is replaced with inert gas, and then the hanger Slightly pull up the gas to open the supply port in the second chamber, supply inert gas into the second chamber, and discharge the dangerous gas into the tank from the lower discharge port, turning the inside of the second chamber into inert gas. Maintenance and inspection of a capacitance type liquid level gauge characterized by replacing the chamber one level below the uppermost chamber in the guide pipe with inert gas, and then pulling up the hanger and performing maintenance and repair. Repair method.