JPS61190486A - Dry-up detector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a dry-up detection device for detecting whether or not the bottom of a cargo oil tank in a tanker is dry after cleaning the cargo oil tank with crude oil.

[Conventional technology]

FIG. 6 is a schematic configuration diagram of a tanker equipped with a conventional dry-up detection device, and FIG. 4 is a configuration diagram of the dry-up detection device. In the figure, 11 is a tanker, 12 is a cargo oil tank of the tanker 11, 16 is a pump room, 14 is an engine room,
15 is a cargo handling control room. 16 is a main stripping pipe installed horizontally on the bottom side of the cargo oil tank 12; 17 is a stripping branch pipe having a horizontal portion branched from the main stripping pipe 16; and 18 is provided at the tip of the stripping branch pipe 17. 19 is a stripping stop valve provided on the base end side of the stripping branch pipe 17; 20 is a stripping stop valve provided in the center of the stripping branch pipe 17 between the stripping stop valve 19 and the bell mouth 18; This is a dry-up detection device. The dry-up detection device 20 is made up of a float chamber 21 and a valve chamber 22. In the float chamber 21, a flap C2-423 is disposed to catch the surface of the oil in the cargo oil tank 12. is a hydraulic switching valve 2 that is turned on and off by the movement of the float 26.
4 are arranged.

The conventional dry-up detection device is configured as described above. For example, at the end of unloading or tank cleaning, the stripping stop valve 19 is opened, and the float 25 in the float chamber 21 of the dry-up detection device 20 is floated by oil. A hydraulic switching valve 24 is opened in the upper part of the float chamber 21, and stripping is performed by driving the illustrated powerful pump in the pump chamber 13. When the oil passing through the stripping branch pipe 17 reaches the final stage of stripping, the float 26 in the float chamber 21 is lowered accordingly, and the oil level reaches the opening surface of the bell mouth 18. When the float 26 has fallen to a certain level, the float 26 is completely lowered, and the hydraulic switching valve 24 in the valve chamber 22 is turned on due to the downward movement of the float 26, detecting that there is no liquid level, that is, the bottom of the cargo oil tank is lowered. It detects whether or not it is dry and issues a detection signal, this detection signal is transmitted to the cargo handling control room 15, and the cargo handling control room 15 takes appropriate measures such as closing the stripping stop valve 19 based on this detection signal. .

[Problem that the invention seeks to solve]

In the conventional dry-up detection device as described above, the oil sucked up from the bell mouth 18 is temporarily stored in the float chamber 21, and the float 16 is moved up and down depending on the amount of storage, thereby completing the presence or absence of the liquid level, that is, stripping. It is designed to detect whether there is a liquid level or not, and does not directly detect the presence or absence of the liquid level. Therefore, when the viscosity of cargo oil is high, the oil stored in the flow chamber 21 solidifies and the float 26 If it stops working or the viscosity of the cargo oil is low, when the liquid level drops to the vicinity of the bell mouth 18, the float 26 is lowered and the hydraulic switching valve 24
There are cases where the stripping operation is performed incorrectly, and there is a problem in that it is not possible to accurately detect the completion of stripping.

[Means for solving problems]

In order to solve the above-mentioned problem, the present invention fixedly installs a pipe containing a reed switch parallel to the bottom of the tank in the direction of the fI leg, and arranges a float with a built-in magnet on the pipe so as to be able to slide freely in parallel. The present invention provides a dry-up detection device characterized by the following.

[For production]

When the oil in the cargo oil tank is pumped out and the oil level falls and approaches the bottom of the ship, the float first rises above the oil surface. Once this happens, as the oil level falls, the float slides along the top of the pipe that houses the reed switch installed on the bottom of the tank. Usually ships are trimmed toward the legs for maneuverability reasons, so most of the residual oil is concentrated in the legs.

Therefore, the float also gradually moves toward the leg and reaches the rear end of the pipe with a built-in reed switch. This makes it possible to automatically detect when the cargo oil tank has become dry.

〔Example〕

The present invention will be explained using figures. FIG. 1 is a schematic diagram showing the configuration of an embodiment of the present invention.

1 is a saddle-shaped float made of an oil-resistant material,
A permanent magnet 2 is built in the center, and guide through holes 4 and 4&4 are provided on both sides to allow guide wires 6 and 6a to pass through.
is provided. Reference numeral 5 denotes a pipe installed in the central part of the ship's cargo oil tank along the ship's bottom longitudinal direction, and has a reed switch 6 built therein. The front and rear ends of the pipe 5 and the guide wire 6.3a are supported by support plates 7, 7a provided in the ship's trunk at the center of the cargo oil tank, as shown in FIG. In the figure, numeral 9 indicates the oil level of residual oil.

Next, this effect will be explained. As the ship's cargo oil loading approaches the end, the oil level in the cargo oil tank falls and the float 1 floats above the oil surface. While sliding, it gradually approaches the support plate 7a on the arm side, guided by the guide wires 6 and 3a. At this time, the reed switch 6 inside the pipe 5 receives the magnetic force of the permanent magnet 2 held by the float 1.
The position of the float 1 can be detected from moment to moment.

When the oil level 9 further falls and the float 1 touches the support plate 7a on the arm side, the float 1 stops, but at this time it is confirmed that the inside of the tank is dry. Although guide wires 3, 6a were used to slide the float 1 along the guide wires 5, rails or the like could also be used.

〔Effect of the invention〕

Conventional detection devices did not directly sense the level of residual oil in the hold, but instead measured the residual oil in the hold indirectly through pressure changes in the pipes, changes in the efficiency of the Stritzbinder bomb, etc., resulting in errors. However, the present invention directly measures the surface of residual oil and is highly reliable because residual oil can be detected reliably. In addition, since the oil level is measured using the ship's trim, it is possible to measure even lower levels than conventional float type level meters.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of an embodiment of the present invention, Fig. 2 is a diagram of installation in a cargo oil tank, Fig. 6 is a configuration diagram of a conventional dry-up detection system, and Fig. 4 is a configuration of a dry-up detection device. It is a diagram. 1: Float, 2: Magnet, 3.5* guide wire,
4.4m guide through hole, 5: pipe, 6: reed switch, 7.7a: support plate.

Claims (1)

[Claims] A dry-up detection device characterized in that a pipe with a built-in reed switch is fixedly installed parallel to the bottom surface of a tank facing in the ■■ direction, and a float with a built-in magnet is arranged on the pipe so as to be able to slide freely in parallel.