JPS6091218A - Inner tube type liquid level gage - Google Patents

Abstract

PURPOSE:To prevent errors in measuring the liquid level of a foaming liquid, by forming upper holes in a long shape in the up and down directions along a guide pipe for breakwater in a liquid level gage. CONSTITUTION:A displacer 2, which yields buoyancy, is attached to a tank 1 and linked to a transmitting device 5 through a rod 3. The buoyance, which is proportional to a liquid level 6, is detected and amplified. The result is transmitted to a display meter (not shown) as an electric signal and displayed. In this liquid level gage, 4 upper air holes 7 are provided in a guide pipe 4 for breakwater of the displacer 2 in the up and down directions along the pipe 4. The holes have a long shape and difference in steps. The two holes face each other at 90 deg. with the other two holes. The width of the hole 7 is about 20- 40mm. and the length thereof is about 100-200mm..

Description

[Detailed description of the invention] The present invention relates to an inner cylinder type liquid level gauge.

Liquid level gauges are extremely common and important instruments in chemical equipment, etc., and a drop in their reliability will immediately affect the operation of the equipment and lead to serious consequences in terms of safety. There are many tables. For this reason, various types of liquid level gauges are used depending on the object to be measured, but an internal cylinder type liquid level gauge is generally used for medium- and low-pressure closed containers and uses buoyancy to indicate the liquid level. As shown in Fig. 1, this liquid level gauge is attached to a tank 1 and connects a displacer 2 that generates buoyancy to a transmitter 5 via a rod 3, detects and amplifies buoyancy proportional to the liquid level 6, and sends an electric signal to an indicator. transmitted and displayed as The guide pipe 4 is used to guide the displacer and to prevent the influence of ripples on the liquid surface.The upper part of the guide pipe has several circular ventilation holes leading to the gas phase of the tank, so that the liquid level inside and outside the guide pipe can be adjusted. It is designed so that there is no difference between the two.

Conventionally, this type of internal cylinder type liquid level gauge has a relatively simple structure and is highly accurate, so it has been used for towing. However, in the case of foaming liquids, it is easy to cause errors in reading due to the resistance caused by the bubbles in the guide pipe. This was a problem because it sometimes became impossible to measure the surface.

The inventors of the present invention have conducted extensive studies on this problem, and have developed a feature in which the upper ventilation hole 7 of the wave-shielding guide pipe 4 is made into an elongated shape that extends upward and downward along the guide pipe. (8 is the mounting flange).

The vertically elongated ventilation holes of the present invention are rectangular or oval shaped at a position above the normal liquid level of the tank, and are arranged in pairs with facing holes at different levels from the pair in the 90° direction, as shown in Figure 3. It is usually sufficient to provide a total of four locations.

The size of each ventilation hole is 20-40 mm wide and 10 mm long.
Approximately 0 to 200 mm is appropriate and should be adjusted appropriately depending on the position of the commonly used liquid level and liquid properties. This will be explained below using examples.

Example In the process of absorbing propylene in sulfuric acid to produce isopropyl sulfuric acid and hydrolyzing it to produce isopropyl alcohol, the reaction liquid leaving the reactor is separated into unreacted hydrocarbons and sulfuric ester in a decanter. Next, the sulfuric acid ester is hydrolyzed to obtain isopropyl alcohol, but when measuring the liquid level in this decanter, a 25 mm
□! An internal cylindrical liquid level gauge held in a guide pipe as shown in Figure 2, which has four circular ventilation holes of n and ψ, was used, but the indication was often incorrect, and an investigation revealed that the reaction liquid was foaming in the decanter. It was determined that this was the cause, so the ventilation hole 7 of the guide pipe was modified to the shape shown in Figure 3.

In this example, the short diameter of the ventilation hole is 25 mm, and the long diameter is 150 mm.
mm, but this method completely eliminated the indication failure.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a general use state of an inner cylinder type liquid level gauge. 2 and 3 are cross-sectional views showing the vent hole of the level gauge guide pipe, FIG. 2 being a conventional circular one, and FIG. 3 being an oval one according to the present invention. Patent developer Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 0) An internal cylinder type liquid level gauge, characterized in that the upper ventilation hole of the wave-shielding guide pipe in the liquid level gauge is formed into an elongated shape vertically extending upward and downward along the guide pipe.