JPH0417368B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid pressure transmitting container for measuring or controlling the flow rate, liquid pressure, liquid level, etc. of a liquid in a process pipe or the like.

When measuring the flow rate, pressure, level, etc. of a liquid in process piping, etc., it is not recommended to introduce the liquid directly into a measuring device if the liquid to be measured is corrosive or poisonous. In some cases, a liquid container is used to transmit pressure or the like to a measuring device or the like via a chemically stable or harmless liquid (hereinafter referred to as a medium liquid).

Conventionally, this type of container is called a seal pot. In conventional seal pots, when a gas such as air gets mixed into the liquid to be measured, the gas is carried along with the liquid and flows into the container, causing the medium liquid to become larger than the liquid to be measured. If the specific gravity is low, this gas will remain permanently in the container, so that compression of the remaining gas will not result in a rapid and correct pressure transfer to the medium liquid.

The present invention provides that when the medium liquid used has a specific gravity lower than the liquid to be measured and gas mixed into the liquid to be measured enters the container, the gas that has entered automatically returns to the liquid to be measured. , which has a structure that excludes gas within the container.

A more specific detailed explanation will be given below with reference to the drawings.

FIG. 1 shows the structure of a conventional seal pot. When the liquid A to be measured enters the seal pot from 1, it pushes up the medium liquid B from below, and the medium liquid B is discharged from the seal pot from the outlet 2 to operate a measuring instrument or a control diaphragm D. In this case, if gas is mixed in the liquid to be measured A, the gas that has entered the seal pot will stay in the upper part C of the seal pot, but this gas will not come into direct contact with the liquid to be measured inlet, and will separate liquid layers A, B, and both liquid layers. Since it is connected to the outside through pressure, it does not come out.

FIG. 2 shows the structure of the seal pot according to the present invention. In FIG. 2, the feature of the present invention is that a partition wall 3 is further provided inside the seal pot to create a double structure. The height of the partition wall 3 is determined by the medium liquid B filled inside it and the measured liquid A outside it.
Considering the ratio of specific gravity, the ratio of the height of the partition wall 3 to the height of the seal pot outer cylinder 4 is determined so that the liquid head inside and outside the partition wall 3 is the same at the lower end of the partition wall 3.

Next, a method for introducing the liquid to be measured A and the medium liquid B will be explained with reference to FIG. First, the medium liquid B is introduced into the seal pot through the medium liquid inlet 5, and is injected until the medium liquid B is discharged from the valve 6 while removing air from the valve 6. After the inside of the inner cylinder 3 and outer cylinder 4 of the seal pot are completely filled with the medium liquid B, the valve 5 is closed, and the medium liquid B is introduced from the liquid to be measured inlet 7.
Inject liquid A to be measured, which has a higher specific gravity. The medium liquid B overflows from the valve 6 again and is injected until the entire inside of the outer cylinder 4 except the inside of the partition wall 3 of the seal pot is replaced with the liquid A to be measured. When liquid A overflows from the valve 6, the valve 6 is closed. With the above operations, bulkhead 3
The inside of the tank is filled with liquid B, and the inside of the seal pot outside the partition wall 3 is filled with liquid A.

Next, the operating situation will be explained with reference to FIG. In order to measure the flow rate, pressure, etc. in the process piping, etc., and to operate the control diaphragm D, the gas contained in the liquid to be measured A introduced into the seal pot first enters the seal pot together with the liquid to be measured A through the introduction pipe 7. However, the gas immediately separates and floats within the seal pot and is discharged from the introduction pipe 7 to the outside of the seal pot, such as inside the process piping, so that the gas does not remain in the outer seal pot and the inner cylinder of the partition wall 3. On the other hand, the liquid to be measured A entering from the introduction tube 7 enters from inside the lower part of the partition wall 3 and pushes up the medium liquid B because the pressure in the diaphragm lower chamber E becomes higher than that in the diaphragm upper chamber F due to the increase in pressure, flow rate, etc. The pushed up medium liquid B moves to the measuring device or control device chamber through the medium liquid outlet pipe 8 and operates the measuring device or control diaphragm D. On the other hand, when the liquid to be measured A is depressurized due to pressure fluctuations on the process side, the pressure inside the seal pot and the measuring part or the control part is also depressurized, so the medium liquid B moves backward and the inside of the partition wall 3 increases, and the inside of the partition wall 3 Press down the measured liquid A.

As mentioned above, liquid B does not move to chamber A when measuring the flow rate or liquid pressure or operating the control port, which involves movement of liquid B in the seal pot, so liquid B does not decrease and the pressure of liquid A is always maintained. It has become possible to transmit fluctuations to the B liquid without delay and to operate the measuring section or the control section with reliable response and high precision.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the structure of a conventional seal pot, and FIGS. 2 and 3 are diagrams showing the structure and operating conditions of the seal pot of the present invention. A... Liquid to be measured, B... Medium liquid, C... Remaining gas, D... Diaphragm for measuring instrument or control, E... Diaphragm lower chamber, F... Diaphragm upper chamber, 1, 7... Measured object Liquid inlet, 2, 8...
...Medium liquid outlet pipe, 3...Partition wall, 4...Seal pot outer cylinder, 5...Medium liquid inlet (valve), 6...
Air vent (valve), 9...medium liquid level confirmation tube.

Claims (1)

[Claims] 1 The specific gravity of the liquid to be measured is measured in the liquid pressure transmission container that takes out the liquid in the process and measures the pressure, flow rate, etc. of the liquid to be measured via the medium liquid, or transmits the pressure, flow rate, etc. to the control unit. When using a medium liquid with a small volume, the container can be divided into two by installing a partition wall with a height ratio selected to the outer cylinder so that the internal and external liquid heads are the same at the lower end, communicating at the lower part. It has a chamber structure, has a medium liquid inside the partition wall and a medium liquid volume confirmation tube for checking the amount of the medium liquid, and has a liquid to be measured outside the partition wall, and a liquid to be measured that is introduced outside the partition wall. As the pressure of the liquid to be measured increases, the medium liquid inside the partition wall is pushed up from below to move the medium liquid to the measuring section or the control section, and when the pressure of the measured liquid decreases, the medium liquid moves in the opposite direction, causing the liquid to move upward. A liquid pressure transmitting container that transmits pressure and has a structure that prevents gas mixed in the liquid to be measured from staying in the container when the liquid to be measured is introduced to the outside of the partition wall of the container.